Water treatment

J Chromatogr A, 2001 Mar 16, 911(2), 225 - 34
Simultaneous quantification of neutral and acidic pharmaceuticals and pesticides at the low-ng/l level in surface and waste water; Ollers S et al.; A new analytical method is presented that allows simultaneous determination of neutral and acidic pharmaceuticals and pesticides in natural waters . The compounds investigated include frequently used pharmaceuticals, i.e., the anti-epileptic carbamazepine, four analgesic/anti-flammatory drugs (ibuprofen, diclofenac, ketoprofen and naproxen) and the lipid regulator clofibric acid and important pesticides including triazines, acetamides and phenoxy acids . Sample enrichment was achieved in one step with a newly developed solid-phase extraction procedure using the Waters Oasis HLB sorbent . The neutral compounds were analyzed by GC-MS in a first step, and then the acidic compounds after derivatization with diazomethane . Relative recoveries using isotope labeled internal standards were between 71 and 118% and the detection limits were in the range of 1 to 10 ng/l in drinking water, surface water and waste water treatment plant effluents (precision: 1-15%) . The developed analytical method proved to be very durable during a 3-month field study and the target analytes were detected in concentrations of 5-3,500 ng/l in waste water treatment plant effluents, river water and lake water.

Sci Total Environ, 2001 Feb 21, 267(1-3), 23 - 31
The importance of ligand speciation in environmental research: a case study; Sillanpaa M et al.; The speciations of EDTA and DTPA in process, waste and river waters are modelled and simulated, specifically to the mode of occurrence in the pulp and paper mill effluents and subsequently in receiving waters . Due to relatively short residence times in bleaching process and waste water treatment and slow exchange kinetics, it is expected that the thermodynamic equilibrium is not necessarily reached . Therefore, the initial speciation plays a key role . As such, the simulations have been extended to the process waters of the pulp and paper industry taking into account estimated average conditions . The results reveal that the main species are; Mn and Ca complexes of EDTA and DTPA in pulp mill process waters; Fe(III) and Mn complexes of EDTA and DTPA in waste waters; Fe(III) and Zn complexes of EDTA and DTPA in receiving waters . It is also shown how the increasing concentration of complexing agents effects the speciation . Alkaline earth metal chelation plays a significant role in the speciation of EDTA and DTPA when there is a noticeable molar excess of complexing agents compared with transition metals.

J Environ Qual, 2001 Mar-Apr, 30(2), 291 - 302
Oxygen-deficient waters along the Japanese coast and their effects upon the estuarine ecosystem; Suzuki T; Development of hypoxia in Japan has been confirmed in the inner part of almost every major bay of Japan on the Pacific Coast from Tokyo southward . This paper presents multiple aspects (present condition, hydraulic mechanism, effect upon fisheries, historical progress and nutrient budget between sediment and water) using Mikawa Bay, where Japan's most serious hypoxia occurs, as an example . Although hypoxia basically results from the increase of nutrient load input from domestic and livestock sources, the intense reclamation of shallows (including tidal flats) and the large reduction in river flow due to farmland irrigation drastically accelerated dissolved oxygen deficiency . Oxygen-deficient waters in Mikawa Bay are large enough to strip the water purification capacity of the remaining shallows . Unfortunately, the shallows have turned from a purifier to a source of nutrient load . These conditions are more or less common in all bays where the dissolved oxygen-deficient waters have been reported . To break this cycle, dissolved oxygen deficiency must be contained to the extent that the purification capacity of the shallows can be restored to an efficient level . For this purpose, the first thing to do is to restore tidal flats over an extensive area and to recover sufficient water flow, which may be a more urgent imperative than reducing the nutrient load input.

Int J Hyg Environ Health, 2001 Mar, 203(3), 215 - 9
Distribution of free-living amoebae (FLA) during preparation and supply of drinking water; Hoffmann R et al.; Free-living amoebae (FLA) are widely distributed in aquatic environments with increasing importance in hygienic, medical and ecological relationship to man . Only few data are available about abundances of these protozoa in the treatment of drinking water and standards in the management of water quality are not suitable for detection of FLA . Prevalence of FLA were investigated within six selected German drinking water treatment plants in the course of the purification-process of surface water and in a subsequent drinking water supply . The data give a short survey about the prevalence and reduction of FLA in processing and supply of drinking water.

Water Res, 2001 Apr, 35(5), 1325 - 33
The application of powdered activated carbon for MIB and geosmin removal: predicting PAC doses in four raw waters; Cook D et al.; Blooms of blue-green algae in reservoirs often produce the musty-earthy taste and odour algal metabolites 2-methylisoborneol (MIB) and geosmin . MIB and geosmin are not removed by conventional water treatment and their presence in the distribution system, even at low ng L-1 levels, can result in consumer complaints . Powdered activated carbon (PAC) can effectively remove MIB and geosmin when the correct dose is applied . The homogeneous surface diffusion model (HSDM) was used to predict PAC doses required to reduce MIB and geosmin concentrations to below 10 ng L-1 at four water treatment plants in Adelaide, South Australia . In jar tests, undertaken under treatment plant conditions, the predicted doses were found to produce water of the desired quality in three of the four waters . The poor predictions found in the fourth water, which had a considerably higher turbidity, were attributed to the incorporation of PAC in a larger, denser floc, leading to a reduced effective contact time of the adsorbent . It was found that higher doses of PAC were required for both compounds to produce acceptable quality water when turbidities rose above 26 NTU.

Water Res, 2001 Apr, 35(5), 1245 - 55
Photocatalytic degradation of the cyanotoxin cylindrospermopsin, using titanium dioxide and UV irradiation; Senogles PJ et al.; Cylindrospermopsis raciborskii produces the cyanotoxin cylindrospermopsin, which is commonly found in SouthEast Queensland water reservoirs, and has been responsible for the closure of these reservoirs as a source of drinking water in recent times . Thus, alternative more effective treatment methods need to be investigated for the removal of toxins such as cylindrospermopsin . This study examined the effectiveness of two brands of titanium dioxide under UV photolysis for the degradation of cylindrospermopsin . Results indicate that titanium dioxide is an efficient photocatalyst for cylindrospermopsin degradation . The titanium dioxide (TiO2), brand Degussa P-25 was found to be more efficient than the alternate brand Hombikat UV-100 . There was an influence from solution pH (4, 7, and 9) with both brands of titanium dioxide, with high pH resulting in the best degradation rate . Importantly, there was no adsorption of cylindrospermopsin to titanium dioxide particles as seen with other cyanotoxins, which would adversely influence the degradation rate . Degradation rates were not influenced by temperature (19-34 degrees C) when P-25 was the source of TiO2, some temperature influence was observed with UV-100 . Dissolved organic carbon concentration will reduce the efficiency of titanium dioxide for cylindrospermopsin degradation, however the presence of other inorganic matter in natural waters greatly assists the photocatalytic process . With minimal potentially toxic by-product formation expected with this treatment, and the effective degradation of cylindrospermopsin, titanium dioxide UV photolysis is a promising speculative alternative water treatment method.

J Med Entomol, 2001 Jan, 38(1), 51 - 4
L-lactic acid as a mosquito (Diptera: Culicidae) repellent on human and mouse skin; Shirai Y et al.; The attraction of Aedes albopictus (Skuse) to hands and forearms of human subjects treated with several concentrations of L-LA solution were studied in a test chamber containing proboscis-amputated mosquitoes . Fewer mosquitoes alighted on L-LA treated human skin than on water-treated control skin . Similar results were found using normal mosquitoes following L-LA and water treatment of mouse skin . The relative repellent effects of L-LA varied with concentration . The minimum repellent concentration was lower than previously reported for human skin . The number of alightments decreased at increasing concentrations of L-LA, demonstrating the absolute repellency of L-LA . Unlike previous reports suggesting that L-LA attracted mosquitoes, our studies using human and mouse skin showed that L-LA exhibited both relative and absolute repellency.

Br J Ophthalmol, 2001 Apr, 85(4), 437 - 43
The specific architecture of the anterior stroma accounts for maintenance of corneal curvature; Muller LJ et al.; AIM: To analyse the human corneal stroma in extreme hydration to discover if its structure is responsible for corneal stability . METHODS: Corneas in several hydration states were used: postmortem control corneas (PM; n=3), corneas left for 1 day in phosphate buffered saline (PBS; n=4), and corneas left for 1 day (n=4), 2 days (n=4), 3 days (n=2), and 4 days (n=4) in deionised water . All corneas were fixed under standardised conditions and processed for light and electron microscopy . In addition, two fresh corneas from the operating theatre were studied which were processed 6 months after storage in sodium cacodylate buffer . RESULTS: After 1 day in deionised water maximal stromal swelling was reached which did not change up to 4 days . The stroma of deionised water corneas (1400 microm) was much thicker than that of PBS corneas (650 microm) and PM corneas (450 microm) . Deionised water treatment led to disappearance of all keratocytes leaving only remnants of nuclei and large interlamellar spaces . In these specimens the distance between the collagen fibres had increased significantly, but the diameter of the collagen fibres did not seem to be affected . A remarkable observation was that the most anterior part of the stroma (100-120 microm) in all deionised water specimens and those stored for 6 months in buffer was not swollen, indicating that the tightly interwoven anterior lamellae are resistant to extreme non-physiological hydration states . CONCLUSIONS: The rigidity of the most anterior part of the corneal stroma in extreme hydration states points to an important role in maintenance of corneal curvature . Since a large part of this rigid anterior part of the stroma is either removed (PRK) or intersected (LASIK), it is possible that in the long run patients who underwent refractive surgery may be confronted with optical problems.

Poult Sci, 2001 Mar, 80(3), 358 - 69
Plasma levels of arginine, ornithine, and urea and growth performance of broilers fed supplemental L-arginine during cool temperature exposure; Ruiz-Feria CA et al.; Two experiments (Experiment 1 and 2) were conducted to evaluate growth performance, ascites mortality, and concentrations of plasma Arg, urea, and ornithine in male broilers raised in floor pens (2 x 4 factorial experiment, six pens for treatment) and exposed to cool temperatures averaging 16 C after 21 d of age . Broilers were fed low- or high-CP diets in both Experiments . In Experiment 1, Arg treatments consisted of control (no supplemental Arg); 0.15 or 0.3% supplemental Arg in the diet (low- and medium-Arg feed, respectively); and 0.3% supplemental Arg in the drinking water (Arg-water) . Arginine levels were increased in Experiment 2 and consisted of the following: control (no supplemental Arg); 0.3 or 0.85% supplemental Arg in the diet (medium- and high-Arg feed, respectively); and 0.6% supplemental Arg in the drinking water (Arg-water) . The water treatment followed a 3-d cyclic regimen, with supplemental Arg being provided for 24 h, followed by tap water for 48 h . When the broilers reached 37 d of age and all groups had consumed tap water for the previous 48 h, blood samples were collected from one bird per pen (Time 0, 0700 h); then supplemental Arg was provided in the Arg-water group, and additional blood samples were collected from the control and Arg-water groups at 3, 6, 12, and 36 h after Time 0 . Plasma amino acids were analyzed using HPLC . Birds fed the high-CP diet were heavier at 49 d than birds fed the low-CP diet in Experiment 1, but not in Experiment 2 . No differences were found in feed conversion or ascites mortality due to CP or Arg treatments in either experiment . In both experiments, plasma Arg was similar for all groups at Time 0, but increased in the Arg-water group at 3, 6, and 12 h after Arg was provided in the water . Within 12 h after returning to tap water, plasma Arg levels of the Arg-water group did not differ from the control group . Plasma urea and ornithine were parallel to plasma Arg concentrations, and the high-CP diets resulted in higher plasma levels of urea and ornithine compared with low-CP diets . These results indicate that kidney arginase was readily activated by Arg provided in the water, resulting in an immediate increase in plasma urea and ornithine . Plasma Arg was increased significantly, but no effects were observed in ascites mortality.

J Colloid Interface Sci, 2001 Apr 1, 236(1), 60 - 66
Dispersion Destabilization in Magnetic Water Treatment; Lipus LC et al.; The destabilization of fine nonmagnetic particles as one of the possible mechanisms for magnetic water treatment (MWT), an alternative method for scale control in industrial water processing and amelioration of dispersion separations, is discussed . Numerical results (based on an electrical double-layer theory) for the theoretical model of surface neutralization due to ion shifts from the bulk of the solution toward the particle surfaces, are presented to show the theoretical possibility of accelerated coagulation of scale-forming particles during and after MWT .

J Environ Monit, 2001 Feb, 3(1), 81 - 5
Speciation of arsenic using solid phase extraction cartridges; Yalcin S et al.; Various solid phase extraction (SPE) cartridges were investigated for speciation of arsenite {As(III)}, arsenate {As(v)}, monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA) . Cartridges containing different types of sorbent materials were tested for arsenic retention and elution characteristics . Alumina cartridges were found to completely retain all the four target arsenic species, and are suitable for removal and preconcentration purposes . For speciation analysis, different arsenic species were separated on the basis of their selective retention on and elution from specific cartridges . DMA was retained on a resin-based strong cation exchange cartridge and eluted with 1.0 M HCl . MMA and As(v) were both retained on a silica-based strong anion exchange cartridge and sequentially eluted with 60 mM acetic acid (for MMA) and 1.0 M HCl {for As(v)} . As(III) was not retained on either cartridge and remained in solution . Arsenic species in solution and those eluted from the cartridges were subsequently quantified by using flow injection with hydride generation atomic fluorescence spectrometry (FI-HGAFS) and hydride generation atomic absorption spectrometry (FI-HGAAS) . A detection limit of 0.05 microg L(-1) arsenic in water sample was achieved using HGAFS . An application of the method was demonstrated at a drinking water treatment facility . As(III) and As(v) species were determined in water at various stages of treatment . The method is suitable for routine determination of trace levels of arsenic in drinking water to comply with more stringent environmental regulations.

J Nutr, 2001 Mar, 131(3s), 1080S - 4S
Pharmacologic activities of aged garlic extract in comparison with other garlic preparations; Kasuga S et al.; We investigated the pharmacologic activities of four garlic preparations, raw garlic juice (RGJ), heated garlic juice (HGJ), dehydrated garlic powder (DGP) and aged garlic extract (AGE) . The study used three animal models, i.e., testicular hypogonadism (hypospermatogensis and impotence) induced by warm water treatment, intoxication of acetaldehyde and growth of inoculated tumor cells . RGJ was found to be effective only in recovery of testicular function . The efficacy of HGJ was observed in three models; however, it did not improve impotence . DGP was effective in recovery of spermatogenesis and stimulated acetaldehyde detoxification . Significant beneficial effects of AGE were found in all three models . Although all four garlic preparations significantly enhanced natural killer (NK) and killer cell activities of the spleen cells of tumor-bearing mice, only AGE and HGJ inhibited the growth of inoculated tumor cells . These results suggest that different types of garlic preparations have different pharmacologic properties, and among the four garlic preparations studied, AGE could be the most useful garlic preparation.

Water Res, 2001 Mar, 35(4), 1106 - 10
Assimilable organic carbon in molecular weight fractions of natural organic matter; Hem LJ et al.; Assimilable organic carbon (AOC) in natural organic matter (NOM) has been measured in three Norwegian waters . The AOC measurement has been done on unfiltered and membrane-filtered (molecular weight (MW) cut-off of 1000 and 10,000) samples . While the colour in the waters is mainly related to the NOM with MW > 10,000, the AOC was mainly related to the NOM with MW < 1000 . The fraction of the NOM with MW < 1000 corresponds to 16-38% of the total organic carbon (TOC), and 4-9% of the colour . This shows that a water treatment process removing the colour and a large part of the TOC in the water will not necessarily result in a reduction in the biofilm formation potential.

Appl Environ Microbiol, 2001 Mar, 67(3), 1225 - 31
Factors influencing numbers of Mycobacterium avium, Mycobacterium intracellulare, and other Mycobacteria in drinking water distribution systems; Falkinham JO 3rd et al.; Eight water distribution systems were sampled over an 18-month period (528 water and 55 biofilm samples) to measure the frequency of recovery and number of mycobacteria, particularly Mycobacterium avium and Mycobacterium intracellulare, in raw source waters before and after treatment and within the distribution system . The systems were chosen to assess the influence of source water, treatment, and assimilable organic carbon levels on mycobacterial numbers . Overall, mycobacterial recovery from the systems was low (15% of samples) . Numbers of mycobacteria ranged from 10 to 700,000 CFU liter(-1) . The number of M . avium in raw waters was correlated with turbidity . Water treatment substantially reduced the number of mycobacteria in raw waters by 2 to 4 log units . Mycobacterial numbers were substantially higher in the distribution system samples (average, 25,000-fold) than in those collected immediately downstream from the treatment facilities, indicating that mycobacteria grow in the distribution system . The increase in mycobacterial numbers was correlated with assimilable organic carbon and biodegradable organic carbon levels (r(2) = 0.65, P = 0.03) . Although M . intracellulare was seldom recovered from water samples, it was frequently recovered (six of eight systems) in high numbers from biofilms (average, 600 CFU/cm(2)) . Evidently, the ecological niches of M . avium and M . intracellulare are distinct.

Water Res, 2001 Feb, 35(2), 448 - 54
Hydrolysis of triphosphate from detergents in a rural waste water system; Halliwell DJ et al.; The concentrations of detergent phosphates in raw sewage entering a small, predominantly domestic waste water treatment facility were determined using an ion chromatographic-flow injection analysis technique . Hourly loads of detergent phosphates were measured between 0600 and 2300 hrs (the major flow period in the plant) on days of both low and high phosphorus loads . The calculated loads of detergent phosphorus entering the plant on low and high load days were 260 g P/day and 350 g P/day, respectively . The half-life of detergent phosphates (triphosphate) in waste waters was measured to be 7.3 hours at 15 degrees C and 3.0 h at 20 degrees C . The major factor contributing to triphosphate degradation in waste water was shown to be biological in nature, with the most likely mechanism being enzymatic hydrolysis.

Water Res, 2001 Feb, 35(2), 419 - 24
Evaluation of two concentration methods for detecting Giardia and Cryptosporidium in water; Hsu BM et al.; The cartridge filtration method and membrane filtration method based on the fluorescent antibody procedure were evaluated for their recovery efficiencies and detection limits of Giardia and Cryptosporidium . We assessed the performances of the two concentration methods for water samples collected from Taiwan water treatment plants . The membrane filtration method was characterized by higher recovery rate and detection limit comparing with the cartridge filtration method . The occurrences of both parasites, and the relationships of parasite concentrations with indicator microorganisms show inconsistency between the two methods . It was discovered that water turbidity reduced the recovery efficiencies, and raised the detection limits for both parasites regardless of the method used.

Water Res, 2001 Mar, 35(3), 675 - 82
Bacterial dynamics in the drinking water distribution system of Brussels; Niquette P et al.; Water samples and pipe coupons were collected from the Brussel's drinking water distribution system (DS) . A treated surface water and various groundwaters feed this DS . Parameters related to bacterial regrowth have been measured on these samples: temperature, concentrations of free residual chlorine, concentration of biodegradable dissolved organic carbon (BDOC), abundance of suspended bacteria, densities of fixed bacteria and levels of bacterial activity . Results showed that groundwaters were less susceptible to favor bacterial regrowth in the DS pipes . Treated surface water and mixed waters had the highest potential of bacterial regrowth in the DS dead ends . Results also showed that the potential regrowth induced by the distribution of a treated surface water could be reduced if: (1) the BDOC levels were below 0.25 mg C/l at the outlet of the surface water treatment plant; (2) a significant free chlorine residual was present within the whole DS . Second-stage biological filtration using granular activated carbon is now under construction at the surface water treatment plant feeding a part of this DS . This treatment implementation should reduce BDOC levels and chlorine demand of the treated surface water and will further reduce the slight regrowth phenomena observed in this DS.

Schriftenr Ver Wasser Boden Lufthyg, 2000, 108, 93 - 123
Safe drinking water production in rural areas: a comparison between developed and less developed countries; Cotruvo JA et al.; At the fundamental level, there are remarkable parallels between developed and less developed countries in problems of providing safe drinking water in rural areas, but of course, they differ greatly in degree and in the opportunities for resolution . Small water supplies frequently encounter difficulty accessing sufficient quantities of drinking water for all domestic uses . If the water must be treated for safety reasons, then treatment facilities and trained operating personnel and finances are always in short supply . Ideally, each solution should be sustainable within its own cultural, political and economic context, and preferably with local personnel and financial resources . Otherwise, the water supply will be continuously dependent on outside resources and thus will not be able to control its destiny, and its future will be questionable . The history of success in this regard has been inconsistent, particularly in less developed but also in some developed countries . The traditional and ideal solution in developing countries has been central water treatment and a piped distribution network, however, results have had a mixed history primarily due to high initial costs and operation and maintenance, inadequate access to training, management and finance sufficient to support a fairly complex system for the long term . These complete systems are also slow to be implemented so waterborne disease continues in the interim . Thus, non-traditional, creative, cost-effective practical solutions that can be more rapidly implemented are needed . Some of these options could involve: small package central treatment coupled with non piped distribution, e.g . community supplied bottled water; decentralized treatment for the home using basic filtration and/or disinfection; higher levels of technology to deal with chemical contaminants e.g . natural fluoride or arsenic . These technological options coupled with training, technical support and other essential elements like community commitment provide opportunities that should be explored both for rural small communities and in rapidly growing periurban areas in developing countries.

Waste Manag, 2001, 21(2), 197 - 203
Treatment of acid lignite mine flooding water by means of microbial sulfate reduction; Glombitza F; During and after mining activities acidic waters containing high amounts of heavy metals and sulfate often occur . In addition to precipitation processes, water purification is also possible with the help of sulfate-reducing bacteria (SRB) . A mixed culture of SRB was adapted to methanol as a cheap carbon source . In order to receive high sulfate-reduction rates immobilization on porous materials proved to be advantageous . Continuous laboratory experiments based on immobilized SRB were carried out with original water from a lignite mining site reaching sulfate-reducing rates up to 132 mg SO4(2-)/(1 h) . Based on these results a process for the treatment of such waters was designed . Heavy metals are removed by recycling sulfide containing effluent, excess sulfide can be oxidized to elemental sulfur by addition of hydrogen peroxide . The plant with a 3.9 m3 bioreactor with immobilized SRB was constructed at the mine site . This pilot plant was operated successfully for some months . The removal of heavy metals was close to 100%, the pH of the acidic water increased from 3.0 to 6.9 . The sulfate-reducing rate again reached 134 mg SO4(2-)/(1 h) . The production of sulfur from the excess sulfide is possible.

J Environ Qual, 2001 Jan-Feb, 30(1), 200 - 9
Artificial recharge of humic ground water; Alborzfar M et al.; The purpose of this study was to investigate the efficiency of soil in removing natural organic matter from humic ground waters using artificial recharge . The study site, in western Denmark, was a 10,000 ml football field of which 2,000 m2 served as an infiltration field . The impact of the artificial recharge was studied by monitoring the water level and the quality of the underlying shallow aquifer . The humic ground water contained mainly humic adds with an organic carbon (OC) concentration of 100 to 200 mg C L(-1) . A total of 5,000 mS of humic ground water were sprinkled onto the infiltration field at an average rate of 4.25 mm h(-1) . This resulted in a rise in the water table of the shallow aquifer . The organic matter concentration of the water in the shallow aquifer, however, remained below 2.7 mg C L(-1) . The organic matter concentration of the pore water in the unsaturated zone was measured at the end of the experiment . The organic matter concentration of the pore water decreased from 105 mg C L(-1) at 0.5 m to 20 mg C L(-1) at 2.5 m under the infiltration field indicating that the soil removed the organic matter from the humic ground water . From these results we conclude that artificial recharge is a possible method for humic ground water treatment.

Scand J Gastroenterol, 2000 Dec, 35(12), 1308 - 13
Chronic inhibition of nitric oxide ameliorates splanchnic hyposensitivity to glypressin in a hemorrhage-transfused rat model of portal hypertension; Huang HC et al.; BACKGROUND: Vasopressin given during hemorrhage is less effective than when given during a stable state in experimental portal hypertension or patients with cirrhosis (the so-called hyposensitivity phenomenon) . This study investigated whether chronic inhibition of nitric oxide (NO) synthesis by NG-nitro-L-arginine methyl ester (L-NAME), a non-selective NO synthase inhibitor, could potentiate the portal-hypotensive effect of glypressin (a long-acting vasopressin analogue) in portal-hypertensive rats during acute bleeding status . METHODS: Portal hypertension was induced by partial portal vein ligation (PVL) . Rats were divided to receive either L-NAME (approximately 25 mg/kg/day in tap water) or placebo (tap water) treatment orally from 2 days prior to until 14 days after the operation . At the end of treatment, L-NAME-and placebo-treated PVL rats were subdivided into without-bleeding and with-bleeding groups to assess the effects of glypressin (0.07 mg/kg) on systemic and portal hemodynamics . In rats with a hypotensive hemorrhage, 4.5 ml of blood was withdrawn and 50% of the withdrawn blood was reinfused before the administration of glypressin . RESULTS: As compared with placebo-treated rats, chronic treatment with L-NAME in PVL rats significantly increased mean arterial pressure (P < 0.001) without modulating portal pressure (P > 0.05) . In placebo-treated PVL rats, glypressin resulted in a less decrease in portal pressure in rats with bleeding than in those without bleeding (P < 0.05) . For PVL rats with bleeding, the portal-hypotensive effect of glypressin was significantly potentiated after chronic L-NAME treatment (P < 0.05) . CONCLUSIONS: Chronic inhibition of NO alleviates the splanchnic hyposensitivity to glypressin observed in bleeding PVL rats, suggesting the pathophysiological role of nitric oxide in mediating this splanchnic hyposensitivity.

J Travel Med, 2001 Jan-Feb, 8(1), 12 - 8
Bacterial removal from inexpensive portable water treatment systems for travelers; Schlosser O et al.; BACKGROUND: There are many personal portable water treatment systems for travelers on the market, including chemical agents, iodine resin purifiers and filters . However, information on the real efficacy of these systems in the field is often lacking . We have therefore estimated the capabilities of several inexpensive personal portable water treatment systems for travelers to remove bacteria in various situations of water quality, using stressed indigenous strains of bacteria . METHODS: Four chemical agents (Drinkwell chlorine, Hydroclonazone, Aquatabs, 2% iodine in ethanol), two iodine resin purifiers (the straw PentaPure Outdoor M1-E, the PentaPure Traveler purifying and filtration system) and four filters (the flexible bottle Pres2Pure, the hand-pump filters Mini Ceramic, First Need Deluxe and WalkAbout) were evaluated in triplicate using both turbid and clear water at 25 degrees C . Bacteria were counted by conventional culturing techniques, colorimetric and fluorescent assays of coliforms and Escherichia coli enzyme activities (Colilert)/Quantitray method), and viable but not culturable bacteria were assessed quantitatively by 5-cyano-2,3-dilotyl-tetrazolium staining . RESULTS: The best systems were the three hand-pump filters, Mini Ceramic, First Need Deluxe, and WalkAbout . All had a submicron filtration element that completely removed 3 log (99.9%) or more of viable bacteria, and no coliforms or E . coli were detected in the effluent . The PentaPure Traveler removed more than 99.3% of the viable bacteria . The only chemical agents that gave a bacterial inactivation of over 2 log in clear water were the Drinkwell chlorine, the Aquatabs, and the 2% iodine in ethanol . The three other devices, Hydroclonazone, Outdoor M1-E, and Pres2Pure, performed poorly, as coliforms and E . coli were detected in the treated water by the Colilert method . The chemical agents and the iodine resin straw performed poorly on raw river water; coliforms and E . coli were detected in the treated water . CONCLUSIONS: These data demonstrate the differences between the systems tested . The effectiveness of other devices on the market should also be tested, so as to help travelers and hikers select the most appropriate portable water treatment system.

Appl Anim Behav Sci, 2001 Feb 16, 71(1), 29 - 42
Effects of an oral dose of acetyl salicylate at tail docking on the behaviour of lambs aged three to six weeks; Pollard JC et al.; To investigate a practical method of providing analgesia for docking of lambs' tails, the effectiveness of an oral dose of aspirin (acetyl salicylate) in reducing discomfort behaviour immediately following application of elastrator rings, was evaluated . The study involved a pilot trial and an experiment, both using Romney crossbred lambs aged 3-6 weeks accompanied by their mothers in a group pen, with behaviour recorded on videotape . In the pilot trial, lambs were manually restrained, an elastrator ring was applied, then lambs were given either an oral dose (26mg/kg) of aspirin dissolved in water (Treatment RA, n=5 lambs) or an oral dose of water (Treatment R, n=4 lambs), and released . RA lambs changed posture between sternal recumbency and standing less frequently than R lambs, significantly so from 10 to 20min post-treatment (11 times for RA, compared with 28% (S.E.D . 6.6%) for R lambs) . In the experiment, 56 lambs were given one of two docking treatments (either RA: application of an elastrator ring plus the same aspirin treatment as in the pilot trial, or R: application of the ring plus water), or one of two control treatments (CA: restraint plus aspirin; or C: restraint plus water) . During the hour after treatment, docking was associated with differences in over three quarters of 52 postures and activities used to describe behaviour (P<0.05), and marked changes over time in the postures/activities affected were observed . Differences were evident within 5min and some were still apparent at 60min post-treatment . When postures and activities were designated as 'normal' or 'abnormal' (typical of docked lambs), over the total hours of observation the mean frequency of abnormal postures was 3.5% for control lambs and 22.6% (S.E.D . 1.64%) for docked lambs, and the mean frequency of abnormal activities was 5.2% for control lambs and 19.3% (S.E.D . 1.40%) for docked lambs . Provision of aspirin to docked lambs was associated with similar levels to those seen in control lambs for two activities but was also associated with increased levels of some activities/postures (P<0.05) . These effects were minor compared with the effects of docking and there was no indication of effective analgesia . Thus, when elastrator tail docking rings were applied, behavioural effects indicative of pain were observed immediately and did not subside fully within 1h . Despite indications in the pilot trial of an analgesic effect of aspirin, further experimentation did not substantiate this effect.

Environ Res, 2001 Feb, 85(2), 77 - 82
Estimation of potential lifetime cancer risks for trihalomethanes from consuming chlorinated drinking water in Taiwan; Hsu CH et al.; Data on concentrations of trihalomethanes (THMs) in raw and chlorinated water collected from three water treatment plants in Taiwan and estimates of the lifetime cancer risk for THMs from drinking water, using age-adjusted factors and volatilization terms, are presented . Data on THM levels in drinking water were obtained from the annual reports of the Environmental Protection Administration (EPA) of Taiwan . The methodology for estimation of lifetime cancer risks was taken from the USEPA . Chloroform was the major species of THMs, especially in the water plant of south Taiwan . Chloroform contributed the majority of the lifetime cancer risks (range: 87.5-92.5%) of total risks from the three water supply areas . All lifetime cancer risks for CHCl(3), CHBrCl(2), CHBr2Cl, and CHBr3 from consuming tap water in the three water supply areas were higher than 10(-6) . The sum of lifetime cancer risks for CHCl(3), CHBrCl(3), CHBr2Cl, and CHBr3 was highest (total risk for total THMs<1.94x10(-4)) for tap water from south Taiwan .

Prostaglandins Leukot Essent Fatty Acids, 2001 Jan, 64(1), 5 - 10
Thromboxane-B2, prostaglandin-E2 and hypertension in the rat 2-kidney 1-clip model: a possible mechanism of the garlic induced hypotension; Al-Qattan KK et al.; Serum collected from unilaterally clipped and unclipped rats before and after treatment with water, garlic or cilazapril and subsequent to measuring blood pressure was assayed for thromboxane-B2 and prostaglandin-E2 . The unclipped rats' thromboxane-B2 and prostaglandin-E2 levels were about 23 ng/ml and 2 ng/ml, respectively, and blood pressure was 126+/-3 mmHg . These values were not affected by either water or garlic administration . The clipped rats' thromboxane-B2 and prostaglandin-E2 concentrations were close to 34 ng/ml and 4 ng/ml, respectively, and declined only in response to garlic (by 15 ng/ml and 3 ng/ml) and cilazapril (by 12 ng/ml and 1.5 ng/ml) . The blood pressure of these rats was 196+/-7 mmHg and again was reduced only by garlic to 169+/-14 mmHg and cilazapril to 137+/-5 mmHg . The no-treatment and water-treatment readings were significantly higher in the clipped rats . The data suggest that prostanoid system activity in the 2-kidney 1-clip rat is enhanced and mostly toward maintaining the hypertension . Furthermore, the blood pressure lowering effects of garlic and cilazapril might have been induced partially by a greater reduction in the synthesis of vasoconstrictor prostanoids .

Bioresour Technol, 2001 Jan, 76(2), 131 - 5
Nutrient removal from polluted river water by using constructed wetlands; Jing SR et al.; The Erh-Ren River is one of the most polluted rivers in Taiwan . Although its flow rate is relatively low, the rate is still beyond the capacity of any traditional water treatment facility . A pilot-scale constructed wetland (CW) is the attempt used to purify the highly polluted river water and to collect data for the construction and operation of a full-scale system in the future . This article reports the results from this initial stage of our research work . During the study, the most efficient nutrient removal occurred between April and October . The monthly average removal rates of chemical oxygen demand (COD) ranged from 13-51% of ammonia-N (AN) from 78-100%, and of orthophosphate (OP) from 52-85% . After November, input COD levels increased, and the monthly average removal rates of ammonia-N dropped to 16% and of orthophosphate to 13% . The dramatic changes in removal efficiency suggest that the macrophytes in the CW had a direct influence on the water treatment and that the change of seasons and the quality of the river water inhibited the growth of the macrophytes.

Ecotoxicol Environ Saf, 2000 Nov, 47(3), 292 - 7
Comparative evaluation of the potential noxiousness in domestic sludge used in agriculture and in commercial fertilizers; Delmas F et al.; The noxiousness of actual sludge collected in eight water treatment plants around the city of Toulouse, France, was evaluated using a biological test based on the growth rate of cultured human cells . Results were compared with those obtained from 18 fertilizers and culture supports that are commercially available in gardening shops . Surprisingly, it was found that sludge extracts, at low concentrations (below 5 g of dry material/liter), were improving the cell growth rate, which suggests the presence of useful oligoelements . At higher concentrations, a noxious effect, expressed as inhibition of cell growth, was observed . However, this negative effect was of the same order of magnitude as that obtained, under the same experimental conditions, with commercial garden fertilizers which are available and used without any restriction . It is concluded that discarding the sludge, after submission to the biological test, in controlled amount as an agricultural fertilizer should not be hazardous to the environment.

Semin Dial, 2000 Nov-Dec, 13(6), 378 - 80
Ultrapure dialysate: a desirable and achievable goal for routine hemodialysis; Ward RA; United States standards for the microbiologic quality of dialysate are not very stringent and have remained unchanged for more than 20 years, despite significant changes in the patient population and in the technology of hemodialysis . Numerous studies have demonstrated that bacterial products can cross dialysis membranes and stimulate an inflammatory response in the patient . Inflammation has been implicated in several complications associated with long-term hemodialysis therapy, and the use of ultrapure dialysate has been shown to reduce the incidence of one of these complications, beta2-microglobulin amyloidosis . Since technological innovations in water treatment and improvements in dialysis machine design allow the routine production of ultrapure dialysate, its use should now become standard.

Semin Dial, 2000 Nov-Dec, 13(6), 372 - 7
Technical advances in hemodialysis therapy; Parker TF 3rd; Other than pharmaceutical advancements, the improvements in hemodialysis have largely been due to technical changes . This article summarizes the various technical areas that are noteworthy: hemodialysis membranes; dialysate buffer, electrolyte concentration, and temperature; prescription monitoring; reprocessing; volume-ultrafiltration control; information system interface; arteriovenous access monitoring; water treatment; and continuous and nocturnal dialysis . Within each category, subjective and objective conclusions are drawn as to whether the technical advancements have translated to improved clinical outcomes . In addition, an hypothesis is proposed that due to a confluence of ownership of research and development, manufacturing of equipment, and dialysis facilities conflicts may arise which could slow future technical developments.

J Chromatogr A, 2000 Nov 3, 897(1-2), 307 - 15
Simultaneous determination of cyanogen chloride and cyanogen bromide in treated water at sub-microg/L levels by a new solid-phase microextraction-gas chromatographic-electron-capture detection method; Cancho B et al.; A headspace solid-phase microextraction (HS-SPME) procedure has been developed and applied for the determination of cyanogen halides in treated water samples at microg/L concentrations . Several SPME coatings were tested, the divinylbenzene-Carboxen-polydimethylsiloxane fiber being the most appropriate coating . GC-electron-capture detection was used for separation and quantitation . Experimental parameters such as sample volume, addition of a salt, extraction time and desorption conditions were studied . The optimized method has an acceptable linearity, good precision, with RSD values <10% for both compounds, and it is sufficiently sensitive to detect ng/L levels . HS-SPME was compared with liquid-liquid microextraction (US Environmental Protection Agency Method 551.1) for the analysis of spiked ultrapure and granular activated carbon filtered water samples . There was good agreement between the results from both methods . Finally, the optimized procedure was applied to determine both compounds at the Barcelona water treatment plant (N.E . Spain) . Cyanogen chloride in treated water was <1.0 microg/L and cyanogen bromide ranged from 3.2 to 6.4 microg/L.

Artif Organs, 2000 Nov, 24(11), 841 - 4
Trace Metals' abnormalities in hemodialysis patients: relationship with medications; Lee SH et al.; A multicenter collaborative study was performed to investigate the prevalence of abnormal blood contents of 6 trace metals, copper (Cu), zinc (Zn), aluminum (Al), lead (Pb), cadmium (Cd), and mercury (Hg), in hemodialysis (HD) patients and to analyze their relationship with the medications, such as CaCO3, Ca acetate, Al containing phosphate-binding agents, 1,25-dihydroxy vitD3, 1-hydroxy vitD3, and erythropoietin (EPO), as well as hematocrit level, by chi-square statistics . From 6 medical centers in Taiwan, we included 456 patients in maintenance HD for more than 4 months for this study, and they had continued the previously mentioned medications for at least 3 months . Blood samples were collected before initiating HD, and atomic absorption spectrophotometry was used to measure plasma levels of Cu, Zn, and Al as well as whole blood levels of Pb, Cd, and Hg . Three hundred seventy-five (78%) of the HD patients had low plasma Zn levels, that is, <800 microg/L, and the mean (+/-SD) concentration was 705.8 (+/-128.23) microg/L in all subjects . One hundred forty-one (31%) of the HD patients had high plasma Al, that is, >50 microg/L, and the mean (+/-SD) was 44.30 (+/-28.28) microg/L in all subjects . Three hundred thirty-three (73%) of the dialysis patients had high Cd levels, that is, >2.5 microg/L, and the mean (+/-SD) was 3.32 (+/-1.49) microg/L in all subjects . The majority of HD patients had normal blood levels of Cu, PB, and Hg . Only 21 (4 . 6%), 5 (1.1%), and 3 (0.06%) patients had elevated blood levels of Cu, Pb, and Hg, respectively . Their mean (+/-SD) blood concentration of Cu, Pb, and Hg were 1,049.78 (+/-233.25) microg/L, 7.45 (+/-3.95) microg/dL, and 3.17 (+/-25.56) microg/L, respectively . Three patients had elevated plasma Hg concentrations, that is, 546, 12.6, and 24.0 microg/L, respectively . In the 152 normal healthy age and sex matched control group, the blood levels of Al, Cd, and Pb were all significantly lower than the HD patients . However, the levels of Cu and Zn were higher in the control group . The Hg level was not significantly different in both groups . There was no statistical difference between patients with normal and abnormal blood levels of trace metals in various medications except Al containing phosphate binder . The Al containing phosphate binder users had significantly higher plasma Al levels (54.71 +/- 26.70 versus 41.15 +/- 28.03 microg/L, p < 0.001) and hematocrit levels (29.61 +/- 4.61 versus 27 . 81 +/- 3.91, p < 0.0005) . There was no statistical correlation between erythropoietin (EPO) dose and hematocrit level in these patients . In conclusion, the blood level of trace metals of these HD patients except Al was not related to their medications . However, caution must be exercised in interpreting this result as dose and duration of medication; efficiency of HD and water treatment may play an important role . Otherwise, environmental factors, diet, and the aging process may contribute to the trace metal burden in uremia . Thus, Zn and Cu are abundant in seafood, and Cd is abundant in contaminated plants such as rice.

Am J Bot, 2000 Dec, 87(12), 1807 - 1814
Seedbed and moisture availability determine safe sites for early Thuja occidentalis (Cupressaceae) regeneration; Cornett MW et al.; Regeneration of many late-successional tree species depends on specialized safe sites . The primary objective was to investigate the roles of seedbed and moisture retention as dimensions of safe sites for the early regeneration of drought-sensitive northern white cedar (Thuja occidentalis) . We hypothesized that rates of germination, survival, and growth of T . occidentalis are unlikely to differ among seedbed types under conditions of abundant water, but that differences are likely to emerge as water becomes more limited . In a 67-d greenhouse experiment, cedar seeds were sown on logs, leaf litter, and soil of cedar and paper birch (Betula papyrifera) canopy origin . Seedbeds were subjected to three water treatments . Among the water treatments, highest germination rates occurred within the high water treatment, although germination on cedar litter was comparable to that of the low water treatment . Higher germination and survival rates occurred on decayed logs than other natural seedbeds for medium (P: = 0.001) and low (P: < 0.0001) water treatments . Germination on birch logs occurred at higher rates than on cedar logs within the low water treatment (P: = 0.04) . Seedling growth for the medium water treatment was lower on leaf litter than any other type of seedbed (P: < 0.01) . Results generally demonstrated that the interplay between seedbed and moisture retention is a component of safe sites for T . occidentalis regeneration.

J Mass Spectrom, 2000 Oct, 35(10), 1197 - 206
Analysis of polar hydrophilic aromatic sulfonates in waste water treatment plants by CE/MS and LC/MS
Loos R, Riu J, Alonso MC, Barcelo D.
The present work describes the development and optimization of a capillary (zone) electrophoresis/mass spectrometric (CE/MS) analysis method for polar hydrophilic aromatic sulfonates (ASs) . The compounds were detected by negative ion electrospray ionization (NIESI) and selected ion monitoring (SIM) . In comparison with CE/UV, for CE/MS a lower-concentration volatile ammonium acetate buffer (5 mM) without organic modifier and a higher separation voltage were better suited for separation . Sensitivity of CE/MS was slightly better than for CF/UV, with the limit of detection (LOD) ranging between 0.1 and 0.4 mg l(-1) . For verification of the CE/MS results, ASs were also analysed by ion-pair liquid chromatography/diode array UV detection coupled in series with electrospray mass spectrometry (IPC/DAD/ESI-MS) . Real water samples of different waste water treatment plants (WWTPs) in Catalonia (NE Spain) were extracted by solid-phase extraction (SPE) with LiChrolut EN and analysed with CE/MS and LC/MS . ASs were found in influent and effluent water samples of the WWTPs in the microg l(-1) concentration range . LC/MS offered a higher separation efficiency and sensitivity than CE/MS . Therefore with LC/MS more compounds could be identified in the WWTPs . The persistency of the ASs was distinct: some compounds were well degraded during the water treatment process, while others were quite persistent.

Int J Food Microbiol, 2000 Nov 1, 61(2-3), 199 - 207
Efficacy of electrolyzed oxidizing (EO) and chemically modified water on different types of foodborne pathogens; Kim C et al.; This study was undertaken to evaluate the efficacy of electrolyzed oxidizing (EO) and chemically modified water with properties similar to the EO water for inactivation of different types of foodborne pathogens (Escherichia coli O157:H7, Listeria monocytogenes and Bacillus cereus) . A five-strain cocktail of each microorganism was exposed to deionized water (control), EO water and chemically modified water . To evaluate the effect of individual properties (pH, oxidation-reduction potential (ORP) and residual chlorine) of treatment solutions on microbial inactivation, iron was added to reduce ORP readings and neutralizing buffer was added to neutralize chlorine . Inactivation of E . coli O157:H7 occurred within 30 s after application of JAW EO water with 10 mg/l residual chlorine and chemically modified solutions containing 13 mg/l residual chlorine . Inactivation of Gram-positive and -negative microorganisms occurred within 10 s after application of ROX EO water with 56 mg/l residual chlorine and chemically modified solutions containing 60 mg/l residual chlorine . B . cereus was more resistant to the treatments than E . coli O157:H7 and L . monocytogenes and only 3 log10 reductions were achieved after 10 s of ROX EO water treatment . B . cereus spores were the most resistant pathogen . However, more than 3 log10 reductions were achieved with 120-s EO water treatment.

AIHAJ, 2000 Sep-Oct, 61(5), 738 - 42
Review of Legionnaires' disease; Shelton BG et al.; This review seeks to assist industrial hygienists in the prevention of Legionnaires' disease caused by Legionella bacteria . Breathing water droplets contaminated with Legionella bacteria, in which the organism has been permitted to amplify, causes this disease . Possible sources of transmission include nearly all manmade building water systems . Legionella organisms, found in most natural water sources but at very low concentrations, can thrive under conditions of warmth in these manmade systems . Primary prevention of Legionnaires' disease requires prevention of amplification of Legionella in water systems . This, in turn, requires familiarity with the system and all its components, and effective maintenance and water treatment . However, good maintenance and water treatment regimens alone cannot assure that amplification will not occur somewhere in the system . Systematic microbiological testing for Legionella and appropriate interpretation of the testing results can be powerful assets in prevention by enabling the detection and control of amplification . The occurrence of a confirmed or suspected case of Legionnaires' disease in a building occupant may indicate transmission within the facility; this poses an immediate crisis for the facility manager . An aggressive intervention is indicated to search for previously unknown additional cases of illness, to detect potential sources of transmission, and to decontaminate any suspected sources of transmission on an emergency basis . Once adequate remediation has been achieved and confirmed by microbiological testing, on-going control measures are essential with periodic microbiological investigation to assure continuing prevention of amplification.

Environ Exp Bot, 2000 Nov 1, 44(3), 185 - 194
The influence of elevated carbon dioxide and water availability on herbaceous weed development and growth of transplanted loblolly pine (Pinus taeda); Gavazzi M et al.; Loblolly pine (Pinus taeda L.) seedlings were grown in competition with native weeds using soil and seed bank collected from recently chopped and burned areas near Appomattox, Virginia . One-year-old seedlings were planted and weeds allowed to germinate from the native seed bank while being exposed to CO(2) (ambient and elevated - approximately 700 ppm) and water (water stressed and well watered) treatments for approximately one growing season in a greenhouse . Elevated CO(2) did not influence total weed biomass; however, C(3) weed community development was favored over C(4) weed community development in elevated CO(2) regardless of water availability . This suggests that weed community composition may shift toward C(3) plants in a future elevated CO(2) atmosphere . Pine growth was significantly greater in the well watered and elevated CO(2) treatments compared to the water stressed and ambient treatments, respectively, even though they were competing with native herbaceous weeds for resources . There was a significant water and CO(2) interaction for pine root:shoot ratio . Under elevated CO(2), root:shoot ratio was significantly greater in the water stressed treatment than the well watered treatment . In contrast, there was no significant difference in the root:shoot ratio under the ambient CO(2) treatment for either water treatment . These results suggest that loblolly pine seedlings will respond favorably in an elevated CO(2) atmosphere, even under dry conditions and competing with herbaceous weeds.

Epidemiol Infect, 2000 Aug, 125(1), 87 - 92
A serological survey of college students for antibody to Cryptosporidium before and after the introduction of a new water filtration plant; Frost FJ et al.; In April 1997, a large city in the northeastern United States changed their drinking water treatment practices . The city, which previously provided only chlorination for their surface water sources added filtration in addition to chlorination . To assess whether Cryptosporidium infections rates declined following filtration, we tested serological responses to 15/17-kDa and 27-kDa Cryptosporidium antigens among 107 community college students 1 month before and 225 students 5 months after filtration . Results suggest that levels of Cryptosporidium infections did not decline following water filtration . However, seasonal changes in other exposures may have confounded the findings . Swimming in a lake, stream or public pool and drinking untreated water from a lake or stream predicted a more intense response to one or both markers . Residence in the city, not drinking city tap water or drinking bottled water, gender, travel or exposure to pets, young pets, diapers or a household child in day care were not found to be predictive of more or less intense serological responses for either the 15/17-kDa and 27-kDa antigen.

Chemosphere, 2000 Aug, 41(3), 363 - 70
Degradation of sodium 4-dodecylbenzenesulphonate photoinduced by Fe(III) in aqueous solution; Mailhot G et al.; The Fe(III)-photoinduced degradation of 4-dodecylbenzenesulphonate (DBS) in aqueous solution was investigated . The mixing of DBS (1 mm) and Fe(III) (1 mm) solutions immediately led to the formation of a precipitate that contained DBS and monomeric Fe(OH)2+, the predominant Fe(III) species . Both species were also present in the supernatant . Irradiation of the supernatant solution resulted in a photoredox process that yielded Fe(II) and *OH radicals . The disappearance of DBS was shown to involve only attack by *OH radicals; the quantum yield of DBS disappearance is similar to the quantum yield of *OH radical formation . A wavelength effect was also observed; the rate of DBS disappearance was higher for shorter wavelength irradiation . Five photoproducts, all containing the benzene sulphonate group, were identified . *OH radicals preferentially abstract hydrogen from the carbon in the alpha position of the aromatic ring . The results show that the Fe(III)-photoinduced degradation of DBS could be used as an alternative method for polluted water treatment.

Risk Anal, 2000 Aug, 20(4), 495 - 511
An integrated risk model of a drinking-water-borne cryptosporidiosis outbreak; Casman EA et al.; A dynamic risk model is developed to track the occurrence and evolution of a drinking-water-borne cryptosporidiosis outbreak . The model characterizes and integrates the various environmental, medical, institutional, and behavioral factors that determine outbreak development and outcome . These include contaminant delivery and detection, water treatment efficiency, the timing of interventions, and the choices that people make when confronted with a known or suspected risk . The model is used to evaluate the efficacy of alternative strategies for improving risk management during an outbreak, and to identify priorities for improvements in the public health system . Modeling results indicate that the greatest opportunity for curtailing a large outbreak is realized by minimizing delays in identifying and correcting a drinking-water problem . If these delays cannot be reduced, then the effectiveness of risk communication in preemptively reaching and persuading target populations to avoid exposure becomes important.

Med Confl Surviv, 2000 Jul-Sep, 16(3), 267 - 80
The impact on civilians of the bombing of Kosovo and Serbia; Ashford MW et al.; Before the 1999 bombing, Kosovo was among the poorest regions in Europe, with low scores on indices of health care . After the war, housing for much of the population is below even basically acceptable standards and health care is disrupted, with serious risk of epidemic diseases . Societal disintegration has led to high levels of stress . In Serbia, also a poor country, which already suffered from high levels of pollution before the war, large amounts of several highly toxic chemicals were liberated into the environment by the bombing . Targeting of electrical generating plant, water treatment facilities, Danube bridges, railways and roads has adverse effects on civilian life, endangers health and seriously affects health care . The military strategy of attack on civilian infrastructures is a war on public health.

Soc Sci Med, 2000 Oct, 51(8), 1211 - 20
To boil or not: drinking water for children in a periurban barrio; Mclennan JD; Boiling water, or other water purification methods, are common recommendations of health promoters in developing countries to improve the quality of drinking water in an attempt to decrease the incidence of childhood diarrhea . Health education programs frequently employ an approach based on knowledge deficits to promote this practice . However, there has been little published about water purification practices or associated variables such as knowledge deficits . We interviewed 266 randomly selected child caregivers about water purification in a poor periurban district of Santo Domingo, Dominican Republic . Though most reported that they provided purified drinking water for their children when they were babies, only half of the children five years of age and under were regularly drinking purified water at the time of the study . Only one knowledge variable remained significantly related to purifying drinking water in the final multivariate model . Other factors that remained in the final model were level of maternal education, endorsing being too tired to boil water and a global measure of social support . Several other hypothesized variables were not related to purifying water . Knowledge deficits may play only a limited role in determining this prevention practice . Further work is required to better identify key factors to improve this practice and hence guide health promotion efforts.

Dtsch Tierarztl Wochenschr, 2000 Aug, 107(8), 311 - 5
{Parasitic zoonotic disease agents in human and animal drinking water}; Karanis P; Human- and veterinary important parasites of the subkingdom of protozoans and helminths infect humans and animals by ingestion of parasites in contaminated water . The parasites are excreted from the body of infected humans, livestock, zoo animals, companion animals or wild animals in the feces . Recreational waters, agricultural practices and wild animals serve as vehicles of transmission of the parasites in the water supplies . The following topics are addressed: a) the life cycles of parasitic diseases-causing agents with proven or potential transmission via water b) the development and the current research status of the analytical techniques for the detection of parasitic diseases-causing agents from water c) the occurrence of Cryptosporidium and Giardia in surface water supplies and in treated water d) the possible water sources and transmission ways of the parasites into the water supplies e) the behaviour and the possibilities for the removal or elimination of the parasites by water treatment.

Environ Health Perspect, 2000 Sep, 108(9), 883 - 6
Relation between stillbirth and specific chlorination by-products in public water supplies; King WD et al.; During water treatment, chlorine reacts with naturally occurring organic matter in surface water to produce a number of by-products . Of the by-products formed, trihalomethanes (THMs) are among the highest in concentration . We conducted a retrospective cohort study to evaluate the relationship between the level of total THM and specific THMs in public water supplies and risk for stillbirth . The cohort was assembled from a population-based perinatal database in the Canadian province of Nova Scotia and consisted of almost 50,000 singleton deliveries between 1988 and 1995 . Individual exposures were assigned by linking mother's residence at the time of delivery to the levels of specific THMs monitored in public water supplies . Analysis was conducted for all stillbirths and for cause-of-death categories based on the physiologic process responsible for the fetal death . Total THMs and the specific THMs were each associated with increased stillbirth risk . The strongest association was observed for bromodichloromethane exposure, where risk doubled for those exposed to a level of {greater and equal to} 20 microg/L compared to those exposed to a level < 5 microg/L (relative risk = 1 . 98, 95% confidence interval, 1.23-3.49) . Relative risk estimates associated with THM exposures were larger for asphyxia-related deaths than for unexplained deaths or for stillbirths overall . These findings suggest a need to consider specific chlorination by-products in relation to stillbirth risk, in particular bromodichloromethane and other by-product correlates . The finding of a stronger effect for asphyxia deaths requires confirmation and research into possible mechanisms.

J Clin Microbiol, 2000 Oct, 38(10), 3681 - 5
Genotyping of rotaviruses in environmental water and stool samples in Southern Switzerland by nucleotide sequence analysis of 189 base pairs at the 5' end of the VP7 gene; Baggi F et al.; Stool specimens from children (<4 years old) with diarrhea were collected over a 1-year period in Ticino (southern region of Switzerland) . During the same period, environmental samples were collected from surface waters in the proximity of major water treatment plants . From treatment plants, samples were collected from the raw sewage and before the release of the treated water . From rivers, samples were collected before and after receiving the treated waters . A single-step reverse transcription (RT)-PCR amplification of the entire VP7 gene from extracted double-stranded RNA was developed . For the water samples, a further nested PCR was necessary to increase sensitivity . All amplified viral products were sequenced, and the sequence profile was compared to that of the VP7 genes of human and animal rotaviruses from GenBank . Rotavirus strains are characterized by outer capsid proteins G (glycoprotein) and P (protease-cleaved protein) . Correct G genotyping of viral sequences from stool and water samples was possible by analyzing only 189 bp at the 5' end of the VP7 gene . In the Ticino region, the most predominant G genotype among clinical and water samples was G1 . Genotypes G2 and G4 were found only among clinical samples . We also detected rotavirus G1-type sequences in feces from a healthy adult . This finding corroborates the hypothesis that healthy adults act as potential reservoirs for the spread of rotavirus in the environment . In our experiments, this RT-PCR-based method for rotavirus genotyping has proven to be a useful tool for epidemiological investigations.

Gig Sanit, 1998 Nov-Dec, (6), 22 - 4
{Organic pollution of the Ural river in the area of open water supply of Orenburg}; Tsinberg MB et al.; The water from the Ural river contains about 230 organic chemical substances, including especially hazardous pollutants . The levels of some chemicals are 2 to 13 times higher than their maximum allowable concentrations . It is necessary to use reliable methods for water treatment at waterworks to lower the levels of drinking water pollutants.

J Dairy Sci, 2000 Aug, 83(8), 1887 - 91
Removal of dairy soil from heated stainless steel surfaces: use of ozonated water as a prerinse; Guzel-Seydim ZB et al.; Square (2.54 x 2.54 cm2) 304 stainless steel metal plates were cleaned, passivated, and soiled by autoclaving (121 degrees C at 15 psi for 15 min) with reconstituted nonfat dry milk (20% solids) . Fifteen-minute treatments using either warm water (40 degrees C) or ozonated cold water (10 degrees C) were conducted to compare prerinse cleaning potential of soiled metal plates . The chemical oxygen demand determination was performed on extracted organic material from treated metal plates . Results indicated that the ozone treatment removed 84% of soil from metal plates versus 51% soil removal by the warm water treatment, but the effectiveness of the two treatments did not differ (P > 0.05) . Cleaning effects were visualized using scanning electron microscopy at 200x and 2000x magnification . The amount of soil film present on stainless steel metal surfaces was visibly lower on ozonated treatments versus on warm water treatments.

J Expo Anal Environ Epidemiol, 2000 Jul-Aug, 10(4), 321 - 6
Household exposures to drinking water disinfection by-products: whole blood trihalomethane levels; Backer LC et al.; Exposure to drinking water disinfection by-products (DBPs), such as trihalomethanes (THMs), has been associated with bladder and colorectal cancer in humans . Exposure to DBPs has typically been determined by examining historical water treatment records and reconstructing study participants' water consumption histories . However, other exposure routes, such as dermal absorption and inhalation, may be important components of an individual's total exposure to drinking water DBPs . In this study, we examined individuals' exposure to THMs through drinking, showering, or bathing in tap water . Thirty-one adult volunteers showered with tap water for 10 min (n = 11), bathed for 10 min in a bathtub filled with tap water (n = 10), or drank 1 l of tap water during a 10 min time period (n = 10) . Participants provided three 10 ml blood samples: one sample immediately before the exposure; one sample 10 min after the exposure ended; and one sample 30 min (for shower and tub exposure) or 1 h ( for ingestion) after the exposure ended . A sample of the water (from the tap, from the bath, or from the shower) was collected for each participant . We analyzed water samples and whole blood for THMs (bromoform, bromodichloromethane, dibromochloromethane, and chloroform) using a purge-and-trap/gas chromatography/mass spectrometry method with detection limits in the parts-per-quadrillion range . The highest levels of THMs were found in the blood samples from people who took 10 min showers, whereas the lowest levels were found in the blood samples from people who drank 1 l of water in 10 min . The results from this study indicate that household activities such as bathing and showering are important routes for human exposure to THMs.

Am J Med Sci, 2000 Aug, 320(2), 96 - 9
Aluminum exposure in chronic renal failure in iberoamerica at the end of the 1990s: overview and perspectives; Fernandez-Martin JL et al.; Epidemic aluminum neurotoxicity has virtually disappeared in the dialysis population; however, sporadic toxic effects caused by contamination of water with aluminum are still reported . In this review, the current situation in Iberoamerica is analyzed . Exposure to aluminum through dialysate shows considerable geographical differences even within the same country, including seasonal variability . Sometimes the tap water showed very high aluminum content that does not permit the water treatment system to efficiently remove all the aluminum, forcing the use of water treatment systems with a double reverse-osmosis filter on line . The use of adequate water treatment systems and a correct control policy has improved the quality of the dialysate, minimizing the aluminum exposure . However, an additional problem in Iberoamerica is the difficulty to obtain aluminum-free concentrates for the preparation of the final dialysis solution . Aluminum still seems to be implicated in a great percentage of symptomatic low-bone remodeling lesions in South America compared with Europe, demonstrating that exposure to aluminum through dialysate is still a cause of concern in some areas of the world.

Acta Cient Venez, 1999, 50 Suppl 1, 75 - 80
{Application of advanced oxidant systems in the treatment of residual waters in the petroleum industry (Fenton system)}; Lopez R et al.; Typical contaminants from the oil industry were treated with the Fenton system (H2O2/Fe2+) under normal conditions of pressure and temperature . The treated contaminants, in harzadous concentrations, were the following: m-cresol, 2-chlorophenol, and methyl-tertbutyl -ether (MTBE) . Additionally, waters contaminated with reformulated gasoline were also treated and the degradation of MTBE and volatile aromatics (benzene, toluene, ethylbenzene and xylene) was followed . The system efficiency, in the contaminated water treatment of two different samples were also tested . One of the samples came from oil production operations and the other from a petrochemical plants complex . In all cases an advanced mineralization of the contaminants was observed in relatively short periods of time . The rate constants, at room temperature, for degradation of m-cresol, 2-chlorophenol and MTBE were measured.

J Hosp Infect, 2000 Aug, 45(4), 263 - 77
Decontamination of minimally invasive surgical endoscopes and accessories; Ayliffe G; Minimal Access Therapy Decontamination Working Group; (1) Infections following invasive endoscopy are rare and are usually of endogenous origin . Nevertheless, infections do occur due to inadequate cleaning and disinfection and the use of contaminated rinse water and processing equipment . (2) Rigid and flexible operative endoscopes and accessories should be thoroughly cleaned and preferably sterilized using properly validated processes . (3) Heat tolerant operative endoscopes and accessories should be sterilized using a vacuum assisted steam sterilizer . Use autoclavable instrument trays or containers to protect equipment during transit and processing . Small bench top sterilizers without vacuum assisted air removal are unsuitable for packaged and lumened devices . (4) Heat sensitive rigid and flexible endoscopes and accessories should preferably be sterilized using ethylene oxide, low temperature steam and formaldehyde (rigid only) or gas plasma (if appropriate) . (5) If there are insufficient instruments or time to sterilize invasive endoscopes, or if no suitable method is available locally, they may be disinfected by immersion in 2% glutaraldehyde or a suitable alternative . An immersion time of at least 10 min should be adopted for glutaraldehyde . This is sufficient to inactivate most vegetative bacteria and viruses including HIV and hepatitis B virus (HBV) . Longer contact times of 20 min or more may be necessary if a mycobacterial infection is known or suspected . At least 3 h immersion in glutaraldehyde is required to kill spores . (6) Glutaraldehyde is irritant and sensitizing to the skin, eyes and respiratory tract . Measures must be taken to ensure glutaraldehyde is used in a safe manner, i.e., total containment and/or extraction of harmful vapour and the provision of suitable personal protective equipment, i.e., gloves, apron and eye protection if splashing could occur . Health surveillance of staff is recommended and should include a pre-employment enquiry regarding asthma, skin and mucosal sensitivity problems and lung function testing by spirometry . (7) Possible alternative disinfectants to glutaraldehyde include peracetic acid (0.2-0.35%), chlorine dioxide (700-1100 ppm) and superoxidized water . These are very effective, killing vegetative bacteria, including mycobacteria, and viruses in 5 min and bacterial spores in 10 min . An endorsement of compatibility with endoscopes, accessories and processing equipment is required from both the solution/device manufacturer and the endoscope manufacturer . Other important considerations are stability, cost and safety from the user and environmental standpoints . (8) Cleaning and disinfection or sterilization should be undertaken by trained staff in a dedicated area, e.g., SSD or TSSU . A suitable training programme is described . (9) If endoscopes are processed by immersion in disinfectants, harmful residues must be removed by thorough rinsing . Sterile or bacteria free water is essential for rinsing all invasive endoscopes and accessories to prevent recontamination . (10) If an automated washer disinfector is used it must be effective, non-damaging, reliable, easy to use and its performance regularly monitored . (11) If used, washer disinfectors and other processing equipment should be disinfected on a regular basis, i.e., between patients or at the start of each session . This will prevent biofilm formation and recontamination of instruments during rinsing . Disinfection should include the water treatment system, if present . (12) To comply with the Medical Devices Directive, manufacturers are obliged to provide full details on how to decontaminate the reusable devices they supply . This should include details of compatibility with heat, pressure, moisture, processing chemicals and ultrasonics . (13) The Infection Control Team should always be involved in the formulation and implementation of decontamination policies . Wherever possible, the national good practice guidelines produced by the Medical Devices Agency and/or professional societies shoul

Environ Health Perspect, 2000 Aug, 108(8), 679 - 84
Use of iodine for water disinfection: iodine toxicity and maximum recommended dose; Backer H et al.; Iodine is an effective, simple, and cost-efficient means of water disinfection for people who vacation, travel, or work in areas where municipal water treatment is not reliable . However, there is considerable controversy about the maximum safe iodine dose and duration of use when iodine is ingested in excess of the recommended daily dietary amount . The major health effect of concern with excess iodine ingestion is thyroid disorders, primarily hypothyroidism with or without iodine-induced goiter . A review of the human trials on the safety of iodine ingestion indicates that neither the maximum recommended dietary dose (2 mg/day) nor the maximum recommended duration of use (3 weeks) has a firm basis . Rather than a clear threshold response level or a linear and temporal dose-response relationship between iodine intake and thyroid function, there appears to be marked individual sensitivity, often resulting from unmasking of underlying thyroid disease . The use of iodine for water disinfection requires a risk-benefit decision based on iodine's benefit as a disinfectant and the changes it induces in thyroid physiology . By using appropriate disinfection techniques and monitoring thyroid function, most people can use iodine for water treatment over a prolonged period of time.

Int J Hyg Environ Health, 2000 Mar, 203(1), 83 - 5
Intestinal cell adhesion and maximum growth temperature of psychrotrophic aeromonads from surface water; Schubert RH; Investigation of 650 Aeromonas strains taken from surface water--used as a source of drinking water--and from the associated drinking water treatment plants has demonstrated that only a small proportion of the strains are endowed with intestinal cell adhesion and growth at 39 degrees C; these characteristics are concurrently encountered in Aeromonas strains from clinical material . The investigations permit the conclusion that even the Aeromonas species, of which certain strains are pathogenic to human, cannot generally be viewed as being potentially pathogenic.

Poult Sci, 2000 Aug, 79(8), 1200 - 3
Efficacy of an herbal extract on the microbiological quality of broiler carcasses during a simulated chill; Dickens JA et al.; Protecta II, an herbal extract on an NaCl carrier, was evaluated in a 30-min, 1 C simulated chill for its effectiveness of lowering microbial counts on broiler carcasses . Eighteen broiler carcasses were obtained from a local processing plant after final wash but before chill, placed into an insulated container, and transported to the research facility for treatment . Six plant run controls (PRC) were immediately bagged on return to the pilot plant, and a whole-carcass rinse was performed . The remaining carcasses were subjected to a 30-min chill (1 C) in tap water or a 2% solution of Protecta II, (n = 6 per treatment) . After treatment, carcasses were rinsed with tap water and subjected to the whole-carcass rinse procedure . All rinse diluents were microbiologically analyzed for total aerobes, coliforms, generic Escherichia coli, and Campylobacter . Six replications were analyzed on 6 different d for a total 36 carcasses per treatment and 36 PRC . The PRC carcasses had 3.7, 2.5, 2.1, and 2.0 log10 cfu/mL for total aerobes, coliforms, generic E . coli, and Campylobacter . Water treatment significantly reduced counts (2.6, 1.4, 0.7, and 0.9 log10 cfu/mL, respectively) when compared with the PRC . Protecta II treatment significantly reduced counts (P < 0.01) even further to counts of 0.06, 0.04, 0.01, and 0.00 log10 cfu/mL for total aerobes, coliforms, Campylobacter, and E . coli, respectively . Detectable levels of the monitored organisms were 1 cell/mL (log10 0) for the E . coli, coliforms, and total counts and 10 cells/mL (log10 1) for the Campylobacter . Microbial counts for carcasses treated with Protecta II would be considered too low to be detected (<1 cell/mL).

Kansenshogaku Zasshi, 2000 Jun, 74(6), 518 - 26
Outbreak of cryptosporidiosis after contamination of the public water supply in Saitama Prefecture, Japan, in 1996; Yamamoto N et al.; An outbreak of cryptosporidiosis occurred in Ogose Town, Saitama Prefecture . Japan, in June 1996 . Of 12,345 respondents to a questionnaire sent to households in the town (population; 13,809), 8,812 (71.4%) reported an acute gastrointestinal illness some time between May and July . In addition, 274 traceable visitors at local inns, golf courses, and the like during this period and 54 employees from out of town were infected . Cases of cryptosporidiosis were estimated to 9,140 . Of these, 2,856 subjects were treated at outpatient clinics and 24 subjects were hospitalized (some subjects counted twice) . No deaths were attributed to the outbreak . Among the visitors to Ogose who were traced, 7 persons who stayed only one day during the outbreak and drank half a glass to 2 glasses (100 to 360 ml) of tap water had cryptosporidiosis confirmed by laboratory tests . The median incubation period for the 14 persons for whom this calculation was possible was 6.4 days (range, 5 to 8 days) . Of 469 pupils reporting details of their fever and diarrhea, abdominal cramps, or these combined signs and symptoms, the median maximum body temperature was 37.8 degrees C (range, 36.7 to 40.3 degrees C) . The duration of illness, reported by 608 of the pupils, was 5.2 days (range, 1 to 15 days), and that reported by 187 employees was 4.8 days (range, 1 to 18 days) . The longest known time for discharge of oocysts after onset was 44 days . Blood was not found in the 609 stool specimens examined . The outbreak was caused by contamination of the town's potable water by Cryptosporidium parvum oocysts . The town's water treatment plant treated river water by coagulation, sedimentation, sand filtration, and chlorination . Contamination arose because of various natural and artificial factors: one was that the monthly precipitation in May was much lower than average, causing the river water level to drop . Another factor was heavy rainfall one night in May that increased water turbidity . The amounts of the coagulant added seemed to be insufficient . There are two inns, three public lavatories, and two small-scale wastewater treatment plants upstream 400 m and 1,200 m of the intake point of the town's water treatment plant . However, there are no farms with livestock in the area . We suggest that the location of the water treatment facilities was inappropriate, and that oocysts had circulated from the potable water to humans to sewage to the river and back to the potable water.

Clin Chem Lab Med, 2000 Mar, 38(3), 221 - 5
Biochemical and hematological changes in low-level aluminum intoxication; Gonzalez-Revalderia J et al.; The aim of this study was to investigate the biochemical and hematological changes in patients on routine hemodialysis treatment when they were accidentally exposed to moderately high serum aluminum concentrations during a period of time of less than four months . We studied the changes in biochemical and hematological measurements in 33 patients on dialysis in our hospital before and during the exposure to about 0.85 pmol/l of aluminum in dialysis water due to a malfunction of the reverse osmosis system of water purification . Patients showed a decrease in the hemoglobin concentration from 115+/-12.4 g/l to 108+/-12.2 g/l (p=0.026) and in the mean corpuscular hemoglobin concentration from 5.15+/-0.22 to 5.02+/-0.30 mmol/l (p=0.014) . Ferritin was decreased from 243+/-192 microg/l to 196+/-163 microg/l (p=0.047) and transferrin saturation from 0.20+/-0.06 to 0.15+/-0.07 (p=0.004) . Biochemical measurements related to calcium-phosphate metabolism did not change . Otherwise, all patients showed an increase in serum aluminum from 0.56+/-0.44 to 1.63+/-0.52 micromol/l (p<0.001) . No differences were detected in serum aluminum between patients receiving and not receiving oral aluminum salts . Even moderately high aluminum concentrations maintained during a short period of time could produce significant hematological alterations and a depletion of body iron stores before clinical manifestations were evident.

Boll Soc Ital Biol Sper, 1998 Nov-Dec, 74(11-12), 111 - 8
Reduction in 222radon concentration due to water treatment processes; Panatto D et al.; In 40 samples of drinkable water taken from public fountains in the Province of Genoa determinations of 222Rn concentration were performed . The results were related to data obtained in a previous study on 222Rn concentration in spring water in the same areas, in order to assess a possible variation due to water treatment and to the aqueduct piping length . Radon concentration was also related to the main geographical areas in the Province and to the different geological formations . The average concentration was 0.92 +/- 0.86 Bq/l, and it can be related to equivalent dose to the population of 0.16 mSv/year . Our data show that water treatment processes cause a reduction in Radon concentration ranging between 58% and 93%, from picking up to utilization.

J Econ Entomol, 2000 Jun, 93(3), 1017 - 20
Hot water treatment and insecticidal coatings for disinfesting limes of mealybugs (Homoptera: Pseudococcidae); Gould WP et al.; Hot water immersion and insecticidal coatings were tested to determine if they could be used to disinfest Persian limes, Citrus latifolia Tanaka, of the mealybug pests Planococcus citri Risso and Pseudococcus odermatti Miller & Williams . A 20-min 49 degrees C hot water immersion treatment is effective in killing mealybugs and all other arthropods tested found externally on limes, or under the calyx . No insects or mites were found to survive after the 20-min hot water treatment . In this test, 7,200 limes were treated with 1,308 insects killed and zero survivors . Treatment at 49 degrees C for 20 min did not significantly affect quality when treated fruit were compared with untreated control fruit . Four coatings were tested at a 3% rate: two petroleum-based oils (Ampol and Sunspray oil), a vegetable oil (natural oil), and a soap (Mpede) . The coatings gave up to 94% kill (Ampol) of mealybugs, which is not sufficient to provide quarantine security . The coatings might be effective as a postharvest dip before shipment.

J Hosp Infect, 2000 Jul, 45(3), 218 - 24
Identification of the bacteriologicalcontamination of a water treatment line used for haemodialysis and its disinfection; Morin P; Renal haemodialysis care units in hospitals use enormous amounts of potable water for the functioning of 'artificial kidneys' . In order to avoid complications with patients' blood this water has to be specially treated . However, the treatment line itself can induce problems due to a high concentration of bacteria in the water . A high bacterial load, as well as bacterial toxins, can provoke immunological reactions in the patients . This paper shows that a granular activated carbon (GAC) filter is a source of bacterial contamination of the water due to the presence of a biofilm on the medium's surface . The majority of the bacteria released are Gram-negative . Because sloughing events in the biofilm can lead to dangerously high concentrations of bacteria and endotoxin levels in water, it is important to control this phenomenon . In treatment lines, GAC filters are regularly chlorinated . Our pilot experiment studied the disinfection of the filter with sodium hypochlorite and peracetic acid . Our results show that both disinfectants have a weak and transient effect on the biomass in the filter . It appears that chemical treatment of the filter is not the ideal solution to the bacteriological threat . Moreover, disinfection of the GAC filter transiently increases the contamination of the water . Alternative solutions to the use of chemical disinfection procedures are discussed.

Br Med Bull, 2000, 56(1), 74 - 83
Microbiological safety of water; Dawson DJ et al.; Significant advances in water treatment over the last century have resulted in massive improvements in the microbiological safety of public drinking water supplies in the UK and the developed countries . Incidences of illness due to poor treatment or post-treatment contamination are rare, but when they occur tend to attract considerable media attention . A well managed water treatment works and supply system can provide high quality drinking water wherever in the world it is located . As a rule, throughout the world, private supplies tend to be of a poorer quality than public supplies, but poorly managed public supplies have the potential to make a large number of people ill and continued effort is needed to maintain and improve drinking water quality world-wide.

Symp Ser Soc Appl Microbiol, 2000, (29), 124S - 132S
Waterborne Escherichia coli O157; Chalmers RM et al.; The waterborne route of Vero cytotoxin-producing E . coli (VTEC) O157 infection was first suggested in two unconnected human cases in 1985 . Since then, waterborne VTEC O157 has been identified in sporadic cases and in outbreaks of illness . Recreational waters, private and municipal supplies have been implicated from microbiological, environmental and epidemiological studies of cases . In addition, a research cohort study of farm workers identified exposure to private water supplies as a risk factor for having antibodies to E . coli O157 . Sources of contamination are thought to be animal and human faeces or sewage . The presence of low numbers of target organisms in water makes microbiological confirmation difficult, therefore epidemiological evidence has been essential in outbreak investigations . Despite the potential for contamination of water with VTEC O157, waterborne infection is relatively rare largely due to the susceptibility of the organism to water treatment processes . This paper presents the evidence for waterborne VTEC O157 infection, considering current microbiological, environmental and particularly epidemiological information.

Symp Ser Soc Appl Microbiol, 2000, (29), 117S - 123S
The fate of Escherichia coli through water treatment and in distribution; McMath SM et al.; The removal of E . coli bacteria at each stage of water treatment is presented, showing how the filtration stages contribute most to reduction of bacterial numbers in the water . At treatment works without filtration stages, the emphasis is put on catchment management to limit contamination of the raw water and ensure that the numbers of viable E . coli in the source water remain low . Routine monitoring of the raw water provides data on seasonal trends in numbers of E . coli bacteria and allows effective management of supply . In the UK there is no evidence that E . coli grows in the water distribution system, whether in the planktonic stage or within biofilms (O'Neill et al . 1997) . The detection of E . coli in the distribution system is rare and prompts a thorough investigation . Repeat samples are taken from the point which originally failed, along with a number of hydraulically linked samples including samples from hydrants . The response to the detection of E . coli is discussed . A series of experiments carried out on a pilot pipe system is briefly described and the results discussed in relation to the routine samples taken in the Thames Water Supply area.

Med Health R I, 2000 May, 83(5), 140 - 3
Water systems to report drinking water quality to all customers: how can health professionals prepare for the questions that these reports will generate?
McCarty K, Swallow J, Vanderslice R, Combs WS Jr.
The ultimate safety of drinking water depends upon protection of source waters and construction and maintenance of reliable drinking water treatment and distribution systems . These objectives require public support . Physicians can encourage their patients to call their water suppliers and advocate for investment in effective treatment systems and support zoning that will protect water supply watersheds and wellheads . The Consumer Confidence Reports are meant to inform consumers about their drinking water supply . Consumers should use the reports to verify that their drinking water meets all health standards and to understand some of the potential threats to their drinking water quality . Physicians may use the reports as an opportunity to discuss the many types of environmental exposures and ways to reduce these exposures . As a crucial component of the public health community, this is your opportunity to encourage your patients to become more aware of their environment and its impact on their health.

Am J Kidney Dis, 2000 Jul, 36(1), 199 - 204
An outbreak of Burkholderia cepacia bacteremia in hemodialysis patients: an epidemiologic and molecular study; Kaitwatcharachai C et al.; The risk of blood stream infections increases in patients undergoing chronic hemodialysis . Outbreaks of infection are usually caused by contamination of the water supply, water treatment, distribution system, or dialyzer reprocessing . We report an outbreak of subclavian catheter-related Burkholderia cepacia bacteremia in nine patients undergoing hemodialysis . Using randomly amplified polymorphic DNA (RAPD) analysis, the bacterial isolates were clonally identical to Burkholderia cepacia isolated from residue of the diluted chlorhexidine-cetrimide solution used to disinfect the transfer forceps . These forceps were used to pick up cotton balls and gauze for dressing the subclavian catheter . Antibiotic therapy failed to cure the infections, and all patients required catheter removal . Pathology showed numerous bacilli embedded in the biofilm on the inner surface of the removed catheters . In conclusion, our study showed that contaminated chlorhexidine-cetrimide solution was the source of a bacteremic outbreak in nine patients who developed catheter-related Burkholderia cepacia infection.

Microb Drug Resist, 2000 Spring, 6(1), 37 - 47
Quinupristin/dalfopristin-resistant enterococci of the satA (vatD) and satG (vatE) genotypes from different ecological origins in Germany; Werner G et al.; The semisynthetic streptogramin combination quinupristin/dalfopristin (Synercid) is a promising alternative for treatment of infections due to multiply resistant gram-positive bacteria including vancomycin-resistant Enterococcus faecium . Resistance is mediated by acetyltransferases SatA (VatD) or SatG (VatE) . Recent papers have indicated a possible link between the use of the streptogramin virginiamycin S/M as a feed additive in commercial animal husbandry and a selection of quinupristin/dalfopristin-resistant E . faecium (QDRE) . We screened manure samples from two different turkey farms and from six different pig farms (using virginiamycin), samples from a sewage water treatment plant, 24 broiler carcasses, 10 pork samples, and 200 stool samples of nonhospitalized humans for QDRE . Our strain culture collection of hospital E . faecium isolates from the last 2 years was also reviewed for QDRE . All manure and sewage samples were positive for QDRE, as well as 11 from broiler carcasses (46%), 1 from pork (10%), and 28 from human stool specimens (14%) . Thirty-six hospital isolates of E . faecium exhibited resistance to quinupristin/dalfopristin . In 141 QDRE of different origin satA (vatD) and satG (vatE) genes were detected (seven isolates from humans with an unknown resistance mechanism) . Streptogramin resistance determinants were tansferable in filtermating experiments for 5 of 10 satA (vatD) and 9 of 22 satG (vatE) isolates . Different EcoRI patterns of satG (vatE) plasmids and corresponding hybridizations of the satG (vatE) gene indicated nonhomologous resistance plasmids in isolates of different origin . The results of this study indicate a common gene pool for streptogramin resistance in E . faecium of different ecological origin . A selection of QDRE using the streptogramin virginiamycin S/M as a feed additive and a spread of the resistance via the food chain to humans is probable.

Schriftenr Ver Wasser Boden Lufthyg, 2000, 105, 413 - 9
Pollution of water sources and removal of pollutants by advanced drinking-water treatment in China; Wang L et al.; The pollution of water resources and drinking water sources in China is described in this paper with basic data . About 90% of surface waters and over 60% of drinking water sources in urban areas have been polluted to different extents . The main pollutants present in drinking water sources are organic substances, ammonia nitrogen, phenols, pesticides and pathogenic micro-organisms, some of which cannot be removed effectively by the traditional water treatment processes like coagulation, sedimentation, filtration and chlorination, and the product water usually does not meet Chinese national drinking water standards, when polluted source water is treated . In some drinking-water plants in China, advanced treatment processes including activated carbon filtration and adsorption, ozonation, biological activated carbon and membrane separation have been employed for further treatment of the filtrate from a traditional treatment system producing unqualified drinking water, to make final product water meet the WHO guidelines and some developed countries' standards, as well as the Chinese national standards for drinking water . Some case studies of advanced water treatment plants are described in this paper as well.

Schriftenr Ver Wasser Boden Lufthyg, 2000, 105, 221 - 6
National Research Council report on potable reuse; Crook J; In 1998, the United States National Research Council prepared a report assessing the viability of potable reuse . The report concludes that planned indirect potable reuse is a viable application of reclaimed water but should be considered for implementation only after other alternative measures, such as development of new water sources, nonpotable reuse, and water conservation, have been evaluated and determined not to be economically or technically feasible . Although health-effects research has not indicated that there have been any adverse health effects resulting from drinking highly treated reclaimed water, those data are sparse . There are uncertainties associated with assessing the potential health risks of drinking reclaimed water . The report acknowledges that several issues remain unresolved regarding reclaimed water treatment and reliability, microbial and chemical constituents of concern, and water quality and health effects monitoring . Research needs include methods to detect emerging pathogens, identification and quantification of trace organic compounds, development of suitable in vivo toxicological methods, and evaluation of the effectiveness and reliability of multiple treatment barriers . The report also concludes that direct potable reuse is not a viable option to consider at this time.

Schriftenr Ver Wasser Boden Lufthyg, 2000, 105, 125 - 31
Resource protection and resource management of drinking water-reservoirs in Thuringia--a prerequisite for high drinking-water quality; Willmitzer H; In face of widespread pollution of surface waters, strategies must be developed for the use of surface waters which protect the high quality standards of drinking water, starting with the catchment area via the reservoir to the consumer . As a rule, priority is given to the avoidance of contaminants directly at their point of origin . Water protection is always cheaper than expensive water-body restoration and water treatment . Complementary to the generally practised technical methods of raw water treatment with all their associated problems of energy input requirements, costs, and waste products, there is an increasing number of environmentally sound treatment technologies which use ecological principles as a basis to support the self-cleaning properties of flowing and dammed waters.

Schriftenr Ver Wasser Boden Lufthyg, 2000, 105, 105 - 10
Water management for development of water quality in the Ruhr River basin; Klopp R; On the Ruhr, a small river running through hilly country and with a mean flow of 76 m3/s, 27 water works use the method of artificial groundwater recharge to produce 350 million m3 of drinking water annually . On the basis of a special act, the Ruhr River Association is responsible for water quality and water quantity management in the Ruhr basin . The present 94 municipal sewage treatment plants ensure that the raw water is sufficiently good to be turned into drinking water . In the Ruhr's lower reaches, where dry weather results in a 20% share of the entire water flow being treated wastewater, comparatively high concentration of substances of domestic or industrial origin are likely, including substances which municipal wastewater treatment measures cannot entirely remove . These substances include ammonium, coliform bacteria or pathogens, boron and organic trace substances . Although water treatment measures have greatly contributed to the considerable improvement of the Ruhr's water quality in the last few decades, it is desirable to continue to aim at a high standard of drinking water production technologies since the Ruhr is a surface water body influenced by anthropogenic factors . However, in the case of substances infiltrating into drinking water, legislation is required if a reduction of pollution appears to be necessary.

Chemosphere, 2000 Sep, 41(5), 751 - 6
Bisphenol A: emissions from point sources; Furhacker M et al.; Bisphenol A is widely used for the production of epoxy resins and polycarbonate plastics . Special in vitro test systems and animal experiments showed a weak estrogenic activity for Bisphenol A . Based on in vitro receptor interaction studies, the activity was estimated to be 2 x 10(-3) lower than that of estradiol . Especially aquatic wildlife could be endangered by waste water discharges . To manage possible risks arising from Bisphenol A contamination, the major fluxes need to be obtained and the contributors to the contamination of municipal treatment plants need to be determined . In this study, industrial emitters and communal waste waters were monitored simultaneously . Mixed samples were taken over periods of one week at nine sample sites . The results showed that the concentrations and fluxes were variable . The paper industry was the major Bisphenol A contributor to the influent of the waste water treatment plant . All the other fluxes measured, including two household areas, were considerably low . About 90% of the total load was removed during the waste water treatment.

Ecotoxicol Environ Saf, 2000 May, 46(1), 29 - 33
Aluminum fractions in drinking water from reservoirs; Schintu M et al.; To provide insight into aluminum speciation in raw and in finished water and to investigate the factors that can affect it, specific aluminum fractions have been isolated and analyzed in water samples from three drinking water reservoirs in Sardinia (Italy) and at the outlet of their treatment plants . All water treatment plants employed polyaluminum chloride as coagulant . The results demonstrate that the treatment of raw water with the aluminum-based coagulant did not increase the concentration of the metal in the finished water . Aluminum fractions were quite different in raw water and in finished water . More than 80% of the aluminum in raw water was in the particulate form . In the dissolved fraction, organic forms were present at higher concentrations in the raw water, while following water treatment (coagulation, flocculation, filtration) most of the aluminum was in the inorganic form . Most of the dissolved Al in raw water was strongly bound or polymeric colloidal, while percentages of monomeric Al ranging from 40 to 62% were present in the finished water .

FEMS Microbiol Lett, 2000 May 15, 186(2), 301 - 6
Tetrahydrofuran degradation by a newly isolated culture of Pseudonocardia sp . strain K1; Kohlweyer U et al.; An organism capable to grow aerobically on tetrahydrofuran as sole source of carbon and energy was isolated from a waste water treatment plant . The organism designated as strain K1 was identified as Pseudonocardia sp . by chemotaxonomic and morphological characteristics as well as analysis of the gene encoding the 16S rRNA . The highest binary sequence similarity value of 99.0% was obtained to Pseudonocardia sulfidoxydans and Pseudonocardia hydrocarbonoxydans . Optimal growth with a doubling time of 14 h was observed at a tetrahydrofuran concentration of 20 mM and pH 7.0 at 28 degrees C . Under these conditions the substrate was completely degraded within 72 h . In situ concentrations of up to 60 mM were tolerated by the organism without a significantly increased doubling time . The strain also grew on diethyl ether, polyethylene glycol and on gamma-butyrolactone and 4-hydroxybutyrate - two potential intermediates in tetrahydrofuran degradation - as sole carbon and energy source.

Mol Cell Probes, 2000 Apr, 14(2), 121 - 6
Quantitative polymerase chain (QPCR) reaction using the MIMIC approach to estimate Cryptosporidium parvum oocysts, an intestinal pathogen, in municipal water treatment sludge samples; Udeh P et al.; An accurate estimation of the number of Cryptosporidium parvum oocysts in water treatment plant sludge was determined using the Quantitative Polymerase Chain Reaction (QPCR) method . Approximately 8x10(6)purified viable oocysts were spiked into raw water and treated by conventional water treatment methods . The settled sludge was collected and the DNA extracted . The QPCR Mimic produced two competing products that were 300 and 435 base pairs in size . The log ratio of the products were used in the standard curve to determine a final estimation of oocysts in the sludge sample . The final number of oocysts in the sludge sample was estimated at 258 oocyst per two litres of treated water . This is the first time sludge from a water treatment process has been tested for presence of C . parvum oocysts, which is a known contaminant of drinking water . The QPCR method can be used to test other sludge samples and help estimate the sanitary risks associated with using sludge to fertilize agricultural lands .

Semin Dial, 2000 Mar-Apr, 13(2), 92 - 6
Outbreaks of infection and/or pyrogenic reactions in dialysis patients; Roth VR et al.; These dialysis-related outbreaks demonstrate the ongoing potential for infection-related morbidity and mortality among dialysis patients . Many of these outbreaks could have been prevented by adequate water treatment, proper disinfection of water systems and dialysis machines, adherence to recommended reprocessing protocols in centers reusing dialyzers, and more stringent quality control monitoring . Finally, these outbreaks highlight the importance of active surveillance for adverse events among dialysis patients . The incidence of gram-negative bacteremia, pyrogenic reactions, and peritonitis should be monitored over time and any increase in incidence investigated.

J Hazard Mater, 2000 Jun 30, 74(3), 133 - 47
The variation of mass and disinfection by-product formation potential of dissolved organic matter fractions along a conventional surface water treatment plant; Marhaba TF et al.; Dissolved organic matter (DOM) influences many aspects of water treatment, including the formation of potentially harmful disinfection by-products (DBPs) when disinfectants are applied . DOM from a conventional surface water treatment plant (WTP) in Northern New Jersey was isolated and fractionated using resin adsorption chromatography into six different fractions . These fractions are operationally categorized as hydrophobic acid, hydrophobic neutral, hydrophobic base, hydrophilic acid, hydrophilic neutral and hydrophilic base . The hydrophilic acid fraction was found to be the most abundant fraction in the source water . The hydrophilic neutral, hydrophilic acid and hydrophobic acid fractions had the highest removal efficiency through the WTP (about 65%) . The variation and removal effectiveness of each fraction along the WTP was studied . Seven-day chlorine DBP formation potential (FP) tests were performed on all DOM fractions through the WTP . For the source water studied, the hydrophilic acid fraction was found to be the most reactive precursor to the trihalomethane (THM) formation . The hydrophobic neutral fraction was found to be the fraction of concern with respect to the FP of haloacetic acids (HAAs) class of DBPs . The FP of each fraction's class of DBPs was found to be amenable for reduction along the treatment train, specifically by coagulation/sedimentation . The fractionated approach concept showed to be very beneficial in the study of DBP precursors and their effective removal by physical and chemical treatment.

J Assoc Physicians India, 1999 Jul, 47(7), 690 - 3
Hypochromic anaemia in chronic renal failure--role of aluminium; Varma PP et al.; BACKGROUND: Anaemia is a cardinal feature of chronic renal failure and classically it is normochromic normocytic . Hypochromic anaemia in these patients is often attributed to iron deficiency . AIM: This study was aimed to find the contribution of aluminium in causation of anaemia in CRF patients . METHODS: Dialysis dependent patients of chronic renal failure with adequate dietary intake (> 1500 Cals/day) and no apparent source of blood loss were evaluated for type of anaemia . (During period of this study centre didn't have reverse osmosis plant for water treatment) . Evaluation included upper GI endoscopy, complete hemogram, serum proteins, serum iron, total iron binding capacity, and bone marrow iron status . For aluminium evaluation serum aluminium levels were done . RESULTS: Sixty-four patients were evaluated for type of anaemia . Mean age of patients was 41.19 years (15-76 years) with male:female ratio 2.3:1 . Classical normochromic picture was seen in 28.5% while rest had hypochromic picture . On bone marrow aspiration study two patients had zero iron stores while all others had normal/excessive iron stores . In 10 patients with hypochromic picture, mean serum aluminium levels were 170 micrograms/L (30-310 micrograms/L) . CONCLUSIONS: This study highlights the high prevalence of hypochromic anaemia in patients with adequate dietary intake and aluminium overload in Indian CRF patients.

J Hosp Infect, 2000 Apr, 44(4), 267 - 72
Investigation of an outbreak of Ralstonia pickettii in a paediatric hospital by RAPD; Maroye P et al.; In 1995, over a 5-day period, Ralstonia pickettii was isolated from six separate blood cultures from six paediatric patients in four different units of the Bordeaux paediatric hospital . The patients did not present fever or any other symptom of septicaemia . Epidemiological investigation cast suspicion on distilled water and 0.05% aqueous solutions of chlorhexidine used for topical disinfection as the source of R . pickettii . The organism was isolated from three of the seven distilled water specimens and from seven of the thirty-seven chlorhexidine specimens collected . Conventional biochemical tests showed no differences between isolates and antimicrobial agent susceptibility testing indicated that the six blood cultures contained the same strain of R . pickettii . This was confirmed by RAPD (random amplified polymorphic DNA) analysis . The primers P3 (5'AGACGTCCAC3') and P15 (5'AATGGCGCAG3') from the kit 'OPH Operon' (Bioprobe Systems, Montreuil, France) were used . The chlorhexidine solutions and the distilled water used to prepare the solutions were contaminated with various strains of R . pickettii including the patient strain . The distilled water originating from the local pharmacy had been deionized on an ion-exchange resin . Circumstantial evidence points to this water treatment as the source of contamination . RAPD proved to be a discriminatory and reproducible technique in this context, but antibiotyping was also very helpful in detecting outbreak and was equally discriminatory .

J Infect Dis, 2000 Apr, 181(4), 1491 - 5 Epub 2000 Apr 13.
Traveler's diarrhea at sea: three outbreaks of waterborne enterotoxigenic Escherichia coli on cruise ships; Daniels NA et al.; Enterotoxigenic Escherichia coli (ETEC) has become the leading bacterial cause of gastroenteritis outbreaks on cruise ships . Investigation of recent outbreaks of ETEC gastroenteritis on 3 cruise ships indicated that all were associated with consuming beverages with ice cubes on board the ship (relative risk {RR}, 1.4, 95% confidence interval {CI}, 1.0-1.9, P=.02; RR, 1.9, 95% CI, 1.3-2 . 9, P<.001; and RR, 1.3, 95% CI, 1.0-1.6, P<.01), and 2 were associated with drinking unbottled water (RR, 2.7, 95% CI, 1.8-4.1, P<.001; RR, 1.7, 95% CI, 1.3-2.3, P<.001) . Multiple ETEC serotypes were detected in patients' stool specimens in each of the 3 outbreaks, and 12 (38%) of 32 isolates were resistant to > or =3 antimicrobial agents . ETEC appears to be emerging as a waterborne pathogen on cruise ships . Water bunkered in overseas ports was the likely source of ETEC infection in these outbreaks . To ensure passenger safety, cruise ships that take on water in foreign ports must ensure that water treatment and monitoring systems function properly.

J Hazard Mater, 2000 Apr 28, 73(3), 221 - 34
Rapid delineation of humic and non-humic organic matter fractions in water; Marhaba TF et al.; Dissolved organic matter (DOM) in water is often characterized by aggregate parameters like dissolved organic carbon (DOC) . DOM from conventional surface water treatment plant in Northern New Jersey was isolated and fractionated using resin adsorption chromatography into six different fractions, which were operationally categorized as hydrophobic acid, hydrophobic neutral, hydrophobic base, hydrophilic acid, hydrophilic neutral and hydrophilic base . The spectral fluorescent signatures (SFS) technique was developed for the quantitative identification of the six fractions by post-processing analysis that includes a statistical model . The SFS is the total sum of emission spectra of a sample at different excitation wavelengths, recorded as a matrix of fluorescent intensity in coordinates of excitation and emission wavelengths, in a definite spectral window . High sensitivity and rapid identification and quantification of DOM fractions are among the main features of the technique . Since hydrophobic and hydrophilic substances are considered more humic and non-humid in nature, respectively, the technique provided an opportunity to rapidly delineate source waters in terms of such categories.

Appl Environ Microbiol, 2000 Apr, 66(4), 1266 - 73
A spore counting method and cell culture model for chlorine disinfection studies of Encephalitozoon syn . Septata intestinalis; Wolk DM et al.; The microsporidia have recently been recognized as a group of pathogens that have potential for waterborne transmission; however, little is known about the effects of routine disinfection on microsporidian spore viability . In this study, in vitro growth of Encephalitozoon syn . Septata intestinalis, a microsporidium found in the human gut, was used as a model to assess the effect of chlorine on the infectivity and viability of microsporidian spores . Spore inoculum concentrations were determined by using spectrophotometric measurements (percent transmittance at 625 nm) and by traditional hemacytometer counting . To determine quantitative dose-response data for spore infectivity, we optimized a rabbit kidney cell culture system in 24-well plates, which facilitated calculation of a 50% tissue culture infective dose (TCID(50)) and a minimal infective dose (MID) for E . intestinalis . The TCID(50) is a quantitative measure of infectivity and growth and is the number of organisms that must be present to infect 50% of the cell culture wells tested . The MID is as a measure of a system's permissiveness to infection and a measure of spore infectivity . A standardized MID and a standardized TCID(50) have not been reported previously for any microsporidian species . Both types of doses are reported in this paper, and the values were used to evaluate the effects of chlorine disinfection on the in vitro growth of microsporidia . Spores were treated with chlorine at concentrations of 0, 1, 2, 5, and 10 mg/liter . The exposure times ranged from 0 to 80 min at 25 degrees C and pH 7 . MID data for E . intestinalis were compared before and after chlorine disinfection . A 3-log reduction (99.9% inhibition) in the E . intestinalis MID was observed at a chlorine concentration of 2 mg/liter after a minimum exposure time of 16 min . The log(10) reduction results based on percent transmittance-derived spore counts were equivalent to the results based on hemacytometer-derived spore counts . Our data suggest that chlorine treatment may be an effective water treatment for E . intestinalis and that spectrophotometric methods may be substituted for labor-intensive hemacytometer methods when spores are counted in laboratory-based chlorine disinfection studies.

Chemosphere, 2000 May-Jun, 40(9-11), 1213 - 20
Rapid anaerobic degradation of toxaphene in sewage sludge; Buser HR et al.; We studied the degradation of technical toxaphene in anaerobic sewage sludge from a municipal waste water treatment plant . Chlorobornanes, chlorocamphenes and related compounds were rapidly degraded, with degradation rates in the order of decachloro>nonachloro>octochloro>heptachloro approximately = hexachloro compounds . The half-lives of individual congeners ranged from <1 day to several days . We also studied the degradation of technical toxaphene in previously sterilized sludge (control), and found it was slower than in the anaerobic sludge . The chlorobornanes that degraded most rapidly in the non-sterilized anaerobic sludge were those with gem chloro substitution on the 6-member carbon-ring, including the toxic congeners, Toxicant A and B . Non-gem chloro substituted congeners, like the biologically persistent P26 and P50, also degraded, but less rapidly . Toxaphene degradation in sewage sludge proceeded primarily via reductive dechlorination, leading to HxSed, HpSed, TC2 and other persistent metabolites . Enantioselective determinations indicated little, if any, enantioselectivity in the formation and/or degradation of these compounds . The isomer and enantiomer profiles of the hexa-, hepta-, and octachlorobornanes are similar to those observed in sediment from the Baltic Sea, suggesting that technical toxaphene is the source of these compounds and that its composition was changed via similar anaerobic degradation pathways.

Int J Infect Dis, 2000, 4(2), 100 - 3
Risk of giardiasis from consumption of wilderness water in North America: a systematic review of epidemiologic data; Welch TP; OBJECTIVES: A meta-analytic study was conducted to test the hypothesis that consumption of water from North American backcountry sources poses a statistically significant risk for acquisition of giardiasis . METHODS: The biomedical literature was surveyed by accessing Medline, and identified studies were supplemented with references in current reviews, published dissertations, and prior communications with state health departments . Studies were classified by methodologic design and subjected to predetermined inclusion criteria . Odds ratios with 95% confidence intervals, chi-squares, and P-values for epidemiologic surveys were either computed from raw data or abstracted directly from the included studies . RESULTS: Of 104 articles identified in the initial screening, nine met the inclusion criteria . Neither of two case reports met the criteria of the Centers for Disease Control and Prevention (CDC) for waterborne disease outbreak . Two prospective studies were identified, but neither showed a significant association . Of four case-control studies providing data, three reported an odds ratio of greater than one . CONCLUSIONS: Published reports of confirmed giardiasis among outdoor recreationalists clearly demonstrate a high incidence among this population . However, the evidence for an association between drinking backcountry water and acquiring giardiasis is minimal . Education efforts aimed at outdoor recreationalists should place more emphasis on handwashing than on water purification . Further studies should attempt to separate the specific risk factor of drinking water from backcountry sources from other behaviors among this group that may contribute to the risk.

Acta Otorhinolaryngol Ital, 1999 Aug, 19(4 Suppl 61), 5 - 14
{Effects of sulphur-arsenic-ferrous water treatment on specific chronic phloglosis of the upper respiratory tract}; Marullo T et al.; The aim of the present study was to demonstrate the therapeutic effect sulphurous-arsenical-ferruginous waters from had on aspecific phlogosis of the upper respiratory tract (URT) . This double-blind study involved treating 37 adults of both sexes with sulphurous-arsenical-ferrignous water (group A) and another 14 subjects, again suffering from the same aspecific, chronic catarrhal disorder and selected with the same criteria, with the aerosol vapor inhalation of drinking water from the city mains (group B) . All subjects included in the study underwent the following tests both before and after the cycle of crenotherapy: Objective E.N.T . examination Anterior Active Computerized Rhinomanometry (AACR) Mucociliary transport time (MTT) Nasal cytology Physical and immunochemical examination of the nasal mucous . The post crenotherapy variations achieved indicate that the sulphurous-ferruginous waters have a beneficial therapeutic effect: indeed, the mucosa was able to perform its complex functions, particularly specific and aspecific defense of the organism . In fact, among other things, group A showed decreased resistance and increased nasal respiratory flow, normalized of mucociliary transport, decreased bacterial layer and increased plasma cells in the rhinocytogram, and an increase in albumin, non secretory immunoglobulin and the secretory portion of secretory immunoglobulin A in the nasal mucosa . None of these variations--many of which were statistically significant--were seen in the controls group treated with drinking water from the public mains.

Toxicon, 2000 Sep, 38(9), 1203 - 13
Degradation of the cyanobacterial toxin cylindrospermopsin, from Cylindrospermopsis raciborskii, by chlorination; Senogles P et al.; Cylindrospermopsin, a potent cyanobacterial toxin produced by Cylindrospermopsis raciborskii and other cyanobacteria, is regularly found in water supplies of Queensland, Australia . This study focussed on the effectiveness of chlorination as a water treatment procedure for cylindrospermopsin degradation . The results demonstrate that relatively low chlorine doses (<1 mg l(-1)) are sufficient for degradation of cylindrospermopsin, when the dissolved organic carbon content is low . However, if organic matter other than cylindrospermopsin is present in the solution, the effectiveness of chlorine for cylindrospermopsin degradation is reduced as other organic matter present consumes chlorine . Under the experimental conditions using samples with a solution pH of 6-9, a residual chlorine concentration of 0.5 mg l(-1)99% of cylindrospermopsin . Toxin degradation via chlorination occurs within the first minute and no difference was observable between degradation in an open system and in a closed system . With a decrease of the pH from 6 to 4 a reduction in the efficiency of chlorine for degradation of cylindrospermopsin was observable, a possible indication that cylindrospermopsin is more stable to chlorine degradation at lower pH . However, in normal water treatment this is not relevant since the pH is consistently higher than 6.

Poult Sci, 2000 Mar, 79(3), 402 - 6
Heterophil to lymphocyte ratio and tonic immobility reactions to preslaughter handling in broiler chickens treated with ascorbic acid; Zulkifli I et al.; Stress and fear responses were evaluated in broiler chicks that were pretreated for 24 h with 0 ppm (control) or 1,200 ppm of L-ascorbic acid (AA) in their drinking water . The birds were subsequently subjected to either upright handling (UH) or inverted (IH) handling for about 45 s . Heterophil (H) counts, lymphocyte (L) counts, and H/L ratios (H/L) ratios were determined immediately (T0) and at 20 h (T20) following the handling treatment . The H/L ratios were similar for both groups at T0, whereas 20 h after the handling treatment, AA-supplemented birds had lower ratios than controls, resulting in a significant water treatment x time of blood sampling interaction . Inverted handling had negligible effect on H/L ratios but augmented tonic immobility (TI) durations as compared with UH . Irrespective of handling procedure, supplemental AA reduced underlying fearfulness, as measured by TI reaction . Neither water treatment nor handling method had significant effect on number of attempts to induce TI.

Wilderness Environ Med, 2000 Spring, 11(1), 12 - 6
Microbiological water purification without the use of chemical disinfection; Gerba CP et al.; OBJECTIVE: Point-of-use (POU) water treatment systems are self-contained units that can be used by recreational enthusiasts who normally obtain drinking water from untreated sources (i.e., rivers, lakes, etc) . Microbiological water purifier units are capable of removing all waterborne pathogens . The purpose of this study was to evaluate a new technology (Structured Matrix) capable of micro-biologically purifying the water without the use of chemical disinfectants or an external power requirement . METHODS: Each of 3 identical portable water filtration units were evaluated for their ability to remove Klebsiella terrigena, poliovirus type 1, rotavirus SA-11, and Cryptosporidium parvum oocysts . Units were operated according to the manufacturer's instructions to process 378 L of water . Each unit was challenged with test organisms after 0, 94, 190, 227, 284, 340, and 378 L had passed through it . For the 227-L and 284-L challenges, a "worst-case" water quality (4 degrees C, pH 9, and turbidity 30 NTU) was used that contained 1500 mg/L dissolved solids and 10 mg/L humid acid . At 340-L and 378-L challenges, worst-case water quality was adjusted to pH 5.0 . Units were tested after stagnation for 48 hours following passage of 190, 340, and 378 L of water . RESULTS: The geometric average removal exceeded 99.9999% for bacteria, 99.99% for viruses, and 99.9% for Cryptosporidium parvum oocysts . CONCLUSION: These units comply with the criteria guidelines for microbial removal under the United States Environmental Protection Agency's "Guide Standard and Protocol for Testing Microbiological Water Purifiers."

Plant Sci, 2000 May 15, 154(1), 83 - 88
Characterization of cDNAs encoding two glycine-rich proteins in chickpea (Cicer arietinum L.): accumulation in response to fungal infection and other stress factors; Cornels H et al.; In chickpea plants infected with the pathogenic fungus Ascochyta rabiei {Pass.} Labr . several mRNAs for two glycine-rich proteins (GRPs) were identified by differential cDNA screening . The main part of the deduced amino acid sequences of the 14.6 kD GRP1 and the larger GRP2 consists of glycine-rich repetitive elements essentially as found for GRPs in other plants . Tyrosine residues in conserved positions inside these repetitive motifs suggest an involvement of the GRPs in a polymerization process by oxidative cross-linking, i.e . cell wall fortification . Both GRP transcripts are induced by infection with A . rabiei, showing a maximum of expression 5 days post infection . Wounding of leaves and the stress of water treatment (performed as a control) also seem to induce the accumulation of GRP transcripts.

EDTNA ERCA J, 1996 Oct-Dec, 22(4), 12 - 4
Water treatment for haemodialysis: not as safe as anticipated; Stragier A; "It is not exaggerated to state that inadequate water treatment is one of the gravest risks posed to the health of the patient on dialysis" . PR Keshaviah . Water purification for haemodialysis relies on a combination of filtration, carbon adsorption, ion exchange and Reverse Osmosis (RO) . This procedure is commonly considered safe and adequate (1).

Food Chem Toxicol, 2000, 38(1 Suppl), S73 - 9
Public health implications of new guidelines for lead in drinking water: a case study in an area with historically high water lead levels; Watt GC et al.; Concern about the neurotoxicity of lead, particularly in infants and young children, has led to a revision of blood lead levels which are considered to involve an acceptable level of human exposure . Drinking water guidelines have also been reviewed in order to reduce this source of population exposure to lead . In the last 20 years, guidelines have been reduced from 100 to 50 to 10 microg/litre . Lead in tap water used to be a major public health problem in Glasgow because of the high prevalence of houses with lead service pipes, the low pH of the public water supply and the resulting high levels of lead in water used for public consumption . Following two separate programmes of water treatment, involving the addition of lime and, a decade later, lime supplemented with orthophosphate, it is considered that maximal measures have been taken to reduce lead exposure by chemical treatment of the water supply . Any residual problem of public exposure would require large scale replacement of lead service pipes . In anticipation of the more stringent limits for lead in drinking water, we set out to measure current lead exposure from tap water in the population of Glasgow served by the Loch Katrine water supply, to compare the current situation with 12 years previously and to assess the public health implications of different limits . The study was based on mothers of young children since maternal blood lead concentrations and the domestic water that mothers use to prepare bottle feeds are the principal sources of foetal and infant lead exposure . An estimated 17% of mothers lived in households with tap water lead concentrations of 10 microg/litre (the {WHO,} guideline) or above in 1993 compared with 49% in 1981 . Mean maternal blood lead concentrations fell by 69% in 12 years . For a given water lead concentration, maternal blood lead concentrations were 67% lower . The mean maternal blood lead concentration was 3.7 microg/litre in the population at large, compared with 3.3 microg/litre in households with negligible or absent tap water lead . Nevertheless, between 63% and 76% of cases of mothers with blood lead concentrations of 10 microg/dl or above were attributable to tap water lead . The study found that maternal blood lead concentrations were well within limits currently considered safe for human health . About 15% of infants may be exposed via bottle feeds to tap water lead concentrations that exceed the WHO guideline of 10 microg/litre . In the context of the health and social problems which affect the well-being and development of infants and children in Glasgow, however, current levels of lead exposure are considered to present a relatively minor health problem.

Food Chem Toxicol, 2000, 38(1 Suppl), S13 - 20
The epidemiology of chemical contaminants of drinking water; Calderon RL; A number of chemical contaminants have been identified in drinking water . These contaminants reach drinking water supplies from various sources, including municipal and industrial discharges, urban and rural run-off, natural geological formations, drinking water distribution materials and the drinking water treatment process . Chemical contaminants for which epidemiologic studies have reported associations include the following: aluminium, arsenic, disinfection by-products, fluoride, lead, pesticides and radon . Health effects reported have included various cancers, adverse reproductive outcomes, cardiovascular disease and neurological disease . In evaluating epidemiologic studies for risk assessment, considering whether the study design was qualitative (hypothesis generating) or quantitative (hypothesis testing) is important and whether sufficient epidemiologic data of a quantitative nature exists to determine the dose-response curve . Each of the chemical contaminants mentioned are summarized by study designs (qualitative and quantitative) and whether a dose-response curve based on epidemiologic data has been proposed . Environmental epidemiology studies are driven by environmental exposures of interest . For drinking water contaminants, the design of epidemiologic studies and their interpretation should consider the following exposure issues: the source of the contaminant; other sources of the contaminant; the route of exposure; the frequency, duration and magnitude of exposure; the ability to document an actual internal dose; and the ability to document the dose to the target organ . Health effects of concern have other risk factors that must be measured in the conduct of these studies . In evaluating epidemiologic studies, potential errors and biases that may occur must be considered given the very low magnitude of associations (less than 2.0 for either odds ratio or risk ratio) . Given the issues, the next generation of drinking water epidemiologic studies should include a multidisciplinary team beyond traditional epidemiologists and statisticians . Study teams will require toxicologists, chemists, engineers and exposure assessors . Arsenic is briefly discussed as an example of the importance of susceptible populations . Disinfection by-products are discussed as an example of epidemiologic studies of mixtures.

Soc Sci Med, 2000 Apr, 50(7-8), 1155 - 66
A longitudinal study of the health impacts of a petroleum refinery; Luginaah IN et al.; Emissions from a petroleum refinery in Oakville, Ont., have been the source of longstanding health concerns among residents in the surrounding community . Between 1992 and 1997, the refinery implemented extensive odour reduction measures through improvements in waste water treatment, in sulphur recovery and combustion . In this paper, we present the main findings of a recent longitudinal analysis using data from community health surveys conducted in 1992 and 1997, before and after implementation of the odour reduction plan . The results show a decline in the frequency of odour perception and annoyance by residents whereas the reporting of cardinal and general symptoms among adults and children was virtually unchanged . Odour perception and annoyance were strongly related to symptom reporting in both years supporting the hypothesis that the effect of refinery emissions on residents' health is odour mediated . The findings extend our understanding of the psychosocial basis of symptom reporting in the vicinity of refineries.

Drug Chem Toxicol, 2000 Feb, 23(1), 307 - 21
A multiple-purpose design approach to the evaluation of risks from mixtures of disinfection by-products; Teuschler LK et al.; Drinking water disinfection has effectively eliminated much of the morbidity and mortality associated with waterborne infectious diseases in the United States . Various disinfection processes, however, produce certain types and amounts of disinfection by-products (DBPs), including trihalomethanes (THM), haloacetic acids, haloacetonitriles, and bromate, among others . Human health risks from the ubiquitous exposure to complex mixtures of DBPs are of concern because existing epidemiologic and toxicologic studies suggest the existence of systemic or carcinogenic effects . Researchers from several organizations have developed a multiple-purpose design approach to this problem that combines efficient laboratory experimental designs with statistical models to provide data on critical research issues (e.g., estimation of human health risk from low-level DBP exposures, evaluation of additivity assumptions as useful for risk characterization, estimation of health risks from different drinking water treatment options) . A series of THM experiments have been designed to study embryonic development, mortality and cancer in Japanese medaka (Oryzias latipes) and liver and kidney endpoints in female CD-1 mice . The studies are to provide dose-response data for specific mixtures of the 4 THMs, for the single chemicals, and for binary combinations . The dose-levels and mixing ratios for these experiments were selected to be useful for development and refinement of three different statistical methods: testing for departures from dose-additivity; development of an interactions-based hazard index; and use of proportional-response addition as a risk characterization method . Preliminary results suggest that dose-additivity is a reasonable risk assessment assumption for DBPs . The future of mixtures research will depend on such collaborative efforts that maximize the use of resources and focus on issues of high relevance to the risk assessment of human health.

Occup Environ Med, 2000 Feb, 57(2), 73 - 85
Chlorination disinfection byproducts in water and their association with adverse reproductive outcomes: a review; Nieuwenhuijsen MJ et al.; OBJECTIVES AND METHODS: Chlorination has been the major disinfectant process for domestic drinking water for many years . Concern about the potential health effects of the byproducts of chlorination has prompted the investigation of the possible association between exposure to these byproducts and incidence of human cancer, and more recently, with adverse reproductive outcomes . This paper evaluates both the toxicological and epidemiological data involving chlorination disinfection byproducts (DBPs) and adverse reproductive outcomes, and makes recommendations for future research . RESULTS AND CONCLUSIONS: Relatively few toxicological and epidemiological studies have been carried out examining the effects of DBPs on reproductive health outcomes . The main outcomes of interest so far have been low birth weight, preterm delivery, spontaneous abortions, stillbirth, and birth defects--in particular central nervous system, major cardiac defects, oral cleft, and respiratory, and neural tube defects . Various toxicological and epidemiological studies point towards an association between trihalomethanes (THMs), one of the main DBPs and marker for total DBP load, and (low) birth weight, although the evidence is not conclusive . Administered doses in toxicological studies have been high and even though epidemiological studies have mostly shown excess risks, these were often not significant and the assessment of exposure was often limited . Some studies have shown associations for DBPs and other outcomes such as spontaneous abortions, stillbirth and birth defects, and although the evidence for these associations is weaker it is gaining weight . There is no evidence for an association between THMs and preterm delivery . The main limitation of most studies so far has been the relatively crude methodology, in particular for assessment of exposure . RECOMMENDATIONS: Large, well designed epidemiological studies focusing on well defined end points taking into account relevant confounders and with particular emphasis on exposure characterisation are ideally needed to confirm or refute these preliminary findings . In practice, these studies may be impracticable, partly due to the cost involved, but this is an issue that can be put right--for example, by use of subsets of the population in the design of exposure models . The studies should also reflect differences of culture and water treatment in different parts of the world . To identify the specific components that may be of aetiological concern and hence to fit the most appropriate exposure model with which to investigate human exposure to chlorinated DBPs, further detailed toxicological assessments of the mixture of byproducts commonly found in drinking water are also needed.

Environ Health Perspect, 2000 Mar, 108 Suppl 1, 113 - 22
Cyanobacterial toxins: removal during drinking water treatment, and human risk assessment; Hitzfeld BC et al.; Cyanobacteria (blue-green algae) produce toxins that may present a hazard for drinking water safety . These toxins (microcystins, nodularins, saxitoxins, anatoxin-a, anatoxin-a(s), cylindrospermopsin) are structurally diverse and their effects range from liver damage, including liver cancer, to neurotoxicity . The occurrence of cyanobacteria and their toxins in water bodies used for the production of drinking water poses a technical challenge for water utility managers . With respect to their removal in water treatment procedures, of the more than 60 microcystin congeners, microcystin-LR (L, L-leucine; R, L-arginine) is the best studied cyanobacterial toxin, whereas information for the other toxins is largely lacking . In response to the growing concern about nonlethal acute and chronic effects of microcystins, the World Health Organization has recently set a new provisional guideline value for microcystin-LR of 1.0 microg/L drinking water . This will lead to further efforts by water suppliers to develop effective treatment procedures to remove these toxins . Of the water treatment procedures discussed in this review, chlorination, possibly micro-/ultrafiltration, but especially ozonation are the most effective in destroying cyanobacteria and in removing microcystins . However, these treatments may not be sufficient during bloom situations or when a high organic load is present, and toxin levels should therefore be monitored during the water treatment process . In order to perform an adequate human risk assessment of microcystin exposure via drinking water, the issue of water treatment byproducts will have to be addressed in the future.

J Epidemiol Community Health, 2000 Jan, 54(1), 45 - 51
Drinking water turbidity and gastrointestinal illness in the elderly of Philadelphia; Schwartz J et al.; STUDY OBJECTIVE: To investigate the association between drinking water quality and gastrointestinal illness in the elderly of Philadelphia . DESIGN: Within the general population, children and the elderly are at highest risk for gastrointestinal disease . This study investigates the potential association between daily fluctuations in drinking water turbidity and subsequent hospital admissions for gastrointestinal illness of elderly persons, controlling for time trends, seasonal patterns, and temperature using Poisson regression analysis . SETTING AND PARTICIPANTS: All residents of Philadelphia aged 65 and older in 1992-1993 were studied through their MEDICARE records . MAIN RESULTS: For Philadelphia's population aged 65 and older, we found water quality 9 to 11 days before the visit was associated with hospital admissions for gastrointestinal illness, with an interquartile range increase in turbidity being associated with a 9% increase (95% CI 5.3%, 12.7%) . In the Belmont service area, there was also an association evident at a lag of 4 to 6 days (9.1% increase, 95% CI 5.2, 13.3) . Both associations were stronger in those over 75 than in the population aged 65-74 . This association occurred in a filtered water supply in compliance with US standards . CONCLUSIONS: Elderly residents of Philadelphia remain at risk of waterborne gastrointestinal illness under current water treatment practices . Hospitalisations represent a very small percentage of total morbidity.

Int J Infect Dis, 2000, 4(1), 3 - 7
Limited effectiveness of home drinking water purification efforts in Karachi, Pakistan; Luby SP et al.; OBJECTIVE: In many developing-country urban areas, municipally supplied water is not microbiologically safe . This study evaluated drinking water quality and effect of home water purification efforts in Karachi, Pakistan . METHODS: Members of 300 households, including 100 households who used the Aga Khan University Hospital Laboratory and 200 of their neighbors were interviewed . In 293 consenting households, structured observations were performed and drinking water was analyzed for the presence of coliforms, using the multiple tube fermentation technique . RESULTS: Although 193 of the 293 households (66%) reported using some method to purify their drinking water, including 169 (58%) who boiled their water, only 48 (16%) of the drinking water samples were free of coliforms . Although a combination of boiling and filtering was the most effective method of purification, only 38% of samples that had been boiled and filtered were free of coliforms . CONCLUSIONS: Further refinements and evaluations of home-based efforts to purify and store water are needed.

Sci Total Environ, 2000 Jan 31, 246(1), 41 - 9
Inhalation exposure to THMs from drinking water in south Taiwan; Lin TF et al.; Trihalomethanes (THMs) are important disinfection byproducts (DBPs) in drinking water . To understand the magnitude of exposure to THMs for the people in southern Taiwan, models are used to estimate the inhalation exposure associated with drinking water based on raw water quality . Two parts of models are used in this study, one for estimating THM concentration from raw water quality, and one for estimating inhalation exposure to people . Important raw water quality and operational parameters, including TOC, UV254, pH, temperature, chlorine dosage, and water residence time of a major water treatment plant in south Taiwan were collected . An empirical THM formation model was then employed to predict the THM concentration at consumers' dwellings based on the parameters collected . Differences between the predicted results and experimental data were found to be small, indicating that the model is appropriate . The predicted THM concentration distribution was served as input parameters for the exposure models . Three major scenarios associated with probable inhalation exposure of THMs, including shower, pre- and post-cooking activities, and cooking processes, were considered in the exposure models . The model results show that the mean inhalation exposure of THMs for shower, pre- and post-cooking activities, and cooking processes are 26.4, 1.56, 3.29 micrograms/day, respectively . The total inhalation exposure (summation of the three scenarios) was found to be comparable with that for direct ingestion, indicating that inhalation is an important pathway for THM exposure from drinking water.

Crit Rev Toxicol, 2000 Jan, 30(1), 71 - 133
Health effects of endocrine-disrupting chemicals on wildlife, with special reference to the European situation; Vos JG et al.; Many wildlife species may be exposed to biologically active concentrations of endocrine-disrupting chemicals . There is strong evidence obtained from laboratory studies showing the potential of several environmental chemicals to cause endocrine disruption at environmentally realistic exposure levels . In wildlife populations, associations have been reported between reproductive and developmental effects and endocrine-disrupting chemicals . In the aquatic environment, effects have been observed in mammals, birds, reptiles, fish, and mollusks from Europe, North America, and other areas . The observed abnormalities vary from subtle changes to permanent alterations, including disturbed sex differentiation with feminized or masculinized sex organs, changed sexual behavior, and altered immune function . For most reported effects in wildlife, however, the evidence for a causal link with endocrine disruption is weak or nonexisting . Crucial in establishing causal evidence for chemical-induced wildlife effects appeared semifield or laboratory studies using the wildlife species of concern . Impaired reproduction and development causally linked to endocrine-disrupting chemicals are well documented in a number of species and have resulted in local or regional population changes . These include: Masculinization (imposex) in female marine snails by tributyltin, a biocide used in antifouling paints, is probably the clearest case of endocrine disruption caused by an environmental chemical . The dogwhelk is particularly sensitive, and imposex has resulted in decline or extinction of local populations worldwide, including coastal areas all over Europe and the open North Sea . DDE-induced egg-shell thinning in birds has caused severe population declines in a number of raptor species in Europe and North America . Endocrine-disrupting chemicals have adversely affected a variety of fish species . In the vicinity of certain sources (e.g., effluents of water treatment plants) and in the most contaminated areas is this exposure causally linked with the effects on reproductive organs that could have implications for fish populations . However, there is also a more widespread occurrence of endocrine disruption in fish in the U.K., where estrogenic effects have been demonstrated in freshwater systems, in estuaries, and in coastal areas . In mammals, the best evidence comes from the-field studies on Baltic gray and ringed seals, and from the Dutch semifield studies on harbor seals, where both reproduction and immune functions have been impaired by PCBs in the food chain . Reproduction effects resulted in population declines, whereas impaired immune function has likely contributed to the mass mortalities due to morbillivirus infections . Distorted sex organ development and function in alligators has been related to a major pesticide spill into a lake in Florida, U.S.A . The observed estrogenic/antiandrogenic effects in this reptile have been causally linked in experimental studies with alligator eggs to the DDT complex . Although most observed effects currently reported concern heavily polluted areas, endocrine disruption is a potential global problem . This is exemplified by the widespread occurrence of imposex in marine snails and the recent findings of high levels of persistent potential endocrine-disrupting chemicals in several marine mammalian species inhabiting oceanic waters.

Am J Kidney Dis, 2000 Feb, 35(2), 244 - 9
Impact of disease severity and hematocrit level on reuse-associated mortality; Ebben JP et al.; Prior studies on reuse-associated mortality have presented conflicting results and included few adjustments for disease severity or hematocrit levels . To evaluate the impact of patient and provider characteristics on reuse-associated mortality, we developed a period-prevalent model with a 6-month entry period . Five cohorts of Medicare hemodialysis patients surviving from July 1 through December 31 of the entry year (1991, 60,985 patients; 1992, 63,081 patients; 1993, 76,018 patients; 1994, 82,899 patients; 1995, 91,761 patients) were followed up for the next year . Using a basic Cox regression survival model (M-1) including age, sex, race, renal diagnosis, prior end-stage renal disease time, unit age, unit size, water treatment, dialysate, and germicide, results were compared with those using a more inclusive model (M-4) adding dialyzer type (conventional or high efficiency/high flux), unit designation (hospital based or freestanding), unit profit status, comorbidity, disease severity, and hematocrit . The previous association of for-profit units with increased mortality was not present after 1994 . Whereas the M-1 analysis showed better survival in reuse units after 1991, the more complete M-4 analysis showed no difference in the risk for mortality between reuse and no-reuse units . We conclude that mortality rates in the United States from 1991 to 1995, when adjusted comprehensively for patient and unit characteristics, were not different in units that practiced reuse and those that did not.

J Chromatogr A, 1999 Dec 24, 864(2), 263 - 70
Ion chromatography determination of trace level bromate by large volume injection with conductivity and spectrophotometric detection after post column derivatisation; Valsecchi S et al.; Bromate is a well known by-product produced by the ozonisation of drinking water; the allowed concentration for human consumption has to be regulated to the low microg l(-1) range . A direct injection, ion chromatographic method was developed using a tetraborate eluent with serially connected conductivity and spectrophotometric detection . Bromate was detected after post-column reaction with fuchsin at 520 nm . Sample capacity was investigated by injecting large volumes (up to 6 ml) using a high total hardness and chloride tap water . Linear correlation of bromate response with volumes from 1 ml to 6 ml was demonstrated, the main limitation being the overlapping of the chloride peak with bromate . Up to 1.5 ml sample can be injected without any pre-treatment . With more than 1.5 ml injection volume, a sample pre-treatment with a cartridge in Ag and H form, followed by a 10 min degassing in an ultrasonic bath, was needed . This method was validated by analysing secondary reference materials and real samples from a drinking water treatment plant . The method was linear from the limit of quantification to 20 microg l(-1) . Reproducibilities in tap water were 18% (5 microg l(-1), n=12) and 21% (1 microg l(-1), n=4) respectively for 1.5 and 6 ml injection volumes with conductivity detection, and 17% at 0.5 microg l(-1) (n=9) with spectrophotometric detection . Calculated detection limits were 0.5 microg l(-1) (6 ml) ahd 2 microg l(-1) (1.5 ml) for conductivity detection and 0.3 microg l(-1) (1.5 ml) for spectrophotometric detection.

Toxicon, 2000 Feb, 38(2), 303 - 8
The adsorption of microcystin-LR by natural clay particles; Morri RJ et al.; The microcystin cyanobacterial hepatotoxins represent an increasingly severe global health hazard . Since microcystins are found world wide in drinking water reservoirs concern about the impact on human health has prompted investigations into remedial water treatment methods . This preliminary study investigates the scavenging from water of microcystin-LR by fine-grained particles known to have a high concentration of the clay minerals kaolinite and montmorillonite . The results show that more than 81% of microcystin-LR can be removed from water by clay material . Thus, microcystin-LR is indeed scavenged from water bodies by fine-grained particles and that this property may offer an effective method of stripping these toxins from drinking water supplies.

Adv Space Biol Med, 1999, 7, 131 - 62
Growing crops for space explorers on the moon, Mars, or in space; Salisbury FB; An option in the long-duration exploration of space, whether on the Moon or Mars or in a spacecraft on its way to Mars or the asteroids, is to utilize a bioregenerative life-support system in addition to the physicochemical systems that will always be necessary . Green plants can use the energy of light to remove carbon dioxide from the atmosphere and add oxygen to it while at the same time synthesizing food for the space travelers . The water that crop plants transpire can be condensed in pure form, contributing to the water purification system . An added bonus is that green plants provide a familiar environment for humans far from their home planet . The down side is that such a bioregenerative life-support system--called a controlled environment life-support system (CELSS) in this paper--must be highly complex and relatively massive to maintain a proper composition of the atmosphere while also providing food . Thus, launch costs will be high . Except for resupply and removal of nonrecycleable substances, such a system is nearly closed with respect to matter but open with respect to energy . Although a CELSS facility is small compared to the Earth's biosphere, it must be large enough to feed humans and provide a suitable atmosphere for them . A functioning CELSS can only be created with the help of today's advanced technology, especially computerized controls . Needed are energy for light, possibly from a nuclear power plant, and equipment to provide a suitable environment for plant growth, including a way to supply plants with the necessary mineral nutrients . All this constitutes the biomass production unit . There must also be food preparation facilities and a means to recycle or dispose of waste materials and there must be control equipment to keep the facility running . Humans are part of the system as well as plants and possibly animals . Human brain power will often be needed to keep the system functional in spite of the best computer-driven controls . The particulars of a CELSS facility depend strongly on where it is to be located . The presence of gravity on the Moon and Mars simplifies the design for a facility on those bodies, but a spacecraft in microgravity is a much more challenging environment . One problem is that plants, which are very sensitive to gravity, might not grow and produce food in the virtual absence of gravity . However, the experience with growing super-dwarf wheat in the Russian space station Mir, while not entirely successful because of the sterile wheat heads, was highly encouraging . The plants grew well for 123 days, producing more biomass than had been produced in space before . This was due to the high photon flux available to the plants and the careful control of substrate moisture . The sterile heads were probably due to the failure to remove the gaseous plant hormone, ethylene, from the Mir atmosphere . Since ethylene can easily be removed, it should be possible to grow wheat and other crops in microgravity with the production of viable seeds . On the ground Biosphere-2 taught us several lessons about the design and construction of a CELSS facility, but Bios-3 came much closer to achieving the goals of such a facility . Although stability was never completely reached, Bios-3 was much more stable than Biosphere-2 apparently because every effort was made to keep the system simple and to use the best technology available to maintain control . Wastes were not recycled in Bios-3 except for urine, and inedible plant materials were incinerated to restore CO2 to the atmosphere . Since much meat (about 20% of calories) was imported, closure in the Bios-3 experiments was well below 100% . But then, a practical CELSS on the Moon might also depend on regular resupply from Earth . Several important lessons have been learned from the CELSS research described in this review.

Occup Med (Lond), 1999 Nov, 49(8), 485 - 9
SWORD '98: surveillance of work-related and occupational respiratory disease in the UK; Meyer JD et al.; The SWORD surveillance scheme, now 10 years old, uses systematic reporting from physicians to provide a picture of the incidence of occupational respiratory disease in the United Kingdom . An estimated total of 2966 incident cases was derived from reports by chest and occupational physicians during the 1998 calendar year . Occupational asthma continues to be the most-reported respiratory condition, with an estimated 822 cases (27% of total cases) . The proportion of cases of mesothelioma (23%), benign pleural disease (21%) pneumoconiosis (7%) and inhalation injuries (6%) remain similar to those estimated in past years, although fewer cases overall were reported . The most commonly identified agents causing asthma in 1998 were enzymes, isocyanates, laboratory animals and insects, colophony and fluxes, flour, latex, and glutaraldehyde . An increased incidence of respiratory diseases of short latency was seen in mining, whilst cases in chemical, mineral products and motor vehicle manufacture remained high; lower rates were noted in wood products and textile manufacture when compared with 1997 figures . Inhalation accidents over the past 3 years were reviewed; gaseous agents and combustion products accounted for nearly half of cases . High rates for inhalation injuries were seen in coal miners, fuel production, motor vehicle manufacturing, water purification, and chemical manufacturing.

Emerg Infect Dis, 2000 Jan-Feb, 6(1), 56 - 9
Burkholderia pseudomallei traced to water treatment plant in Australia; Inglis TJ et al.; Burkholderia pseudomallei was isolated from environmental specimens 1 year after an outbreak of acute melioidosis in a remote coastal community in northwestern Australia . B . pseudomallei was isolated from a water storage tank and from spray formed in a pH-raising aerator unit . Pulsed-field gel electrophoresis confirmed the aerator and storage tank isolates were identical to the outbreak strain, WKo97.

Mutat Res, 1999 Dec 17, 431(2), 397 - 415
Measurement of HPRT mutations in splenic lymphocytes and haemoglobin adducts in erythrocytes of Lewis rats exposed to ethylene oxide; Tates AD et al.; Young adult male Lewis rats were exposed to ethylene oxide (EO) via single intraperitoneal (i.p.) injections (10-80 mg kg-1) or drinking water (4 weeks at concentrations of 2, 5, and 10 mM) or inhalation (50, 100 or 200 ppm for 4 weeks, 5 days week-1, 6 h day-1) to measure induction of HPRT mutations in lymphocytes from spleen by means of a cloning assay . N-ethyl-N-nitrosourea (ENU) and N-(2-hydroxyethyl)-N-nitrosourea (HOENU) were used as positive controls . Levels of N-(2-hydroxyethyl)valine (HOEtVal) adducts in haemoglobin (expressed in nmol g-1 globin) were measured to determine blood doses of EO (mmol kg-1 h, mM h) . Blood doses were used as a common denominator for comparison of mutagenic effects of EO administered via the three routes . The mean HPRT mutant frequency (MF) of the historical control was 4.3 x 10(-6) . Maximal mean MFs for ENU (100 mg kg-1) and HOENU (75 mg kg-1) were 243 x 10(-6) and 93 x 10(-6), respectively . In two independent experiments, EO injections led to a statistically significant dose-dependent induction of mutations, with a maximal increase in MF by 2.3-fold over the background . Administration of EO via drinking water gave statistically significant increases of MFs in two independent experiments . Effects were, at most, 2.5-fold above the concurrent control . Finally, inhalation exposure also caused a statistically significant maximal increase in MF by 1.4-fold over the background . Plotting of mutagenicity data (i.e., selected data pertaining to expression times where maximal mutagenic effects were found) for the three exposure routes against blood dose as common denominator indicated that, at equal blood doses, acute i.p . exposure led to higher observed MFs than drinking water treatment, which was more mutagenic than exposure via inhalation . In the injection experiments, there was evidence for a saturation of detoxification processes at the highest doses . This was not seen after subchronic administration of EO . The resulting HPRT mutagenicity data suggest that EO is a relatively weak mutagen in T-lymphocytes of rats following exposure(s) by i.p . injection, in drinking water or by inhalation.

JAMA, 2000 Jan 12, 283(2), 242 - 9
Weapons of mass destruction events with contaminated casualties: effective planning for health care facilities; Macintyre AG et al.; Biological and chemical terrorism is a growing concern for the emergency preparedness community . While health care facilities (HCFs) are an essential component of the emergency response system, at present they are poorly prepared for such incidents . The greatest challenge for HCFs may be the sudden presentation of large numbers of contaminated individuals . Guidelines for managing contaminated patients have been based on traditional hazardous material response or military experience, neither of which is directly applicable to the civilian HCF . We discuss HCF planning for terrorist events that expose large numbers of people to contamination . Key elements of an effective HCF response plan include prompt recognition of the incident, staff and facility protection, patient decontamination and triage, medical therapy, and coordination with external emergency response and public health agencies . Controversial aspects include the optimal choice of personal protective equipment, establishment of patient decontamination procedures, the role of chemical and biological agent detectors, and potential environmental impacts on water treatment systems . These and other areas require further investigation to improve response strategies.

Chemosphere, 1999 Dec, 39(15), 2651 - 9
Model reactor for photocatalytic degradation of persistent chemicals in ponds and waste water; Franke R et al.; A laboratory scale flow-through model reactor for the degradation of persistent chemicals using titanium dioxide (TiO2) as photocatalyst immobilized on glass beads is presented . In the test system with a volume of 18 L contaminated water is pumped to the upper part of the floating reactor and flows over the coated beads which are exposed to UV-radiation . The degradation of two dyes of different persistence was investigated . Primary degradation of methylene blue did not fit a first order kinetic due to coincident adsorption onto the photocatalyst and direct photolysis, resulting in a half-life of 6 h . A filtrate of a green algae suspension accelerated the colour removal . In contrast, reactive red 2 was degraded only by photocatalysis; neither adsorption nor direct photolysis led to a colour removal . The course of primary degradation followed a first order kinetic with a half-life of 18 h and a rate constant of 0.04 h-1 . Analysis of the degradation products indicated mineralization by detection of NO2- and NO3-, accompanied by a decrease of pH and an increase of conductivity . A successful adaptation of the model reactor (scale 1:10) to dimensions required for surface waters and waste water treatment plants would be a cost-efficient and environmentally sustainable application of photocatalysis for the treatment of industrially polluted water and could be of relevance for third world countries, particularly those favoured by high solar radiation.

Biodegradation, 1999, 10(4), 271 - 8
Fate of the herbicides mecoprop, dichlorprop, and 2,4-D in aerobic and anaerobic sewage sludge as determined by laboratory batch studies and enantiomer-specific analysis; Zipper C et al.; Aerobic degradation experiments with the racemic mixtures of mecoprop and dichlorprop revealed that activated sludge collected from the aeration tank of a municipal waste water treatment plant degraded both enantiomers of mecoprop and dichlorprop within 7 days, albeit in an enantioselective manner; the (S) enantiomers were preferentially degraded . Mecoprop, dichlorprop, and 2,4-D were completely metabolized under aerobic conditions, as shown by the 86-98% elimination of dissolved organic carbon . Under anaerobic conditions, the concentration of 2,4-D decreased exponentially with a first-order reaction rate constant of 0.24 per day and without a lag-phase . After an incubation time of 17 days, 2,4-D was completely removed . 2,4-Dichlorophenol was the main metabolite of anaerobic 2,4-D degradation; only traces of 4-chlorophenol were detected . In contrast, the chiral phenoxypropionic acid herbicides mecoprop and dichlorprop persisted under anaerobic conditions during 49 days of incubation.

Lab Anim, 1984 Jan, 18(1), 45 - 51
An evaluation of a water purification system for use in animal facilities; Raynor TH et al.; A commercially available water purification system was evaluated for its ability to minimize chemical and microbial contaminants . The reduction or removal of these impurities from the drinking water of experimental animals would reduce experimental variability . 3 strains of bacteria were collected from the processed water . An increase in the total number of bacteria was observed the longer the filters remained in use . Determinations of heavy metals in water samples before and after processing were made for lead, zinc, copper, nickel, manganese, iron, arsenic and mercury . Calcium and magnesium levels were also determined . The concentrations of these inorganic chemicals were reduced by the purification process except at 2 time points in which desorption of the chemical could have occurred . Bacterial colonization and desorption of these chemicals were controlled by installing new filter cartridges . Volatile halocarbon concentrations were determined for water samples before and after purification . All volatile halocarbons analyzed were less than 10 ppb before and after purification at all time points . Other organic chemicals were greatly reduced by the purification process . In a study of contaminants associated with installation of the unit, it was found that flushing the unit for 8 days reduced lead and methyl ethyl ketone concentrations to insignificant levels . The purification system was found to be effective in providing high quality drinking water as verified by a microbial and chemical testing program.

Appl Environ Microbiol, 2000 Jan, 66(1), 268 - 76
A pilot study of bacteriological population changes through potable water treatment and distribution; Norton CD et al.; This pilot study compares the compositions of bacterial biofilms in pipe networks supplied with water containing either high levels of biodegradable organic matter (BOM) or low levels of BOM (conventionally or biologically treated, respectively) . The Microbial Identification System for fatty acid analysis was utilized in this study to identify a large number of organisms (>1,400) to determine population changes in both conventionally and biologically treated water and biofilms . Data generated during this study indicated that suspended bacteria have little impact on biofilms, and despite treatment (conventional or biological), suspended microbial populations were similar following disinfection . Prechlorination with free chlorine resulted not only in reduced plate count values but also in a dramatic shift in the composition of the bacterial population to predominately gram-positive bacteria . Chlorination of biologically treated water produced the same shifts toward gram-positive bacteria . Removal of assimilable organic carbon by the biologically active filters slowed the rate of biofilm accumulation, but biofilm levels were similar to those found in conventionally treated water within several weeks . Iron pipes stimulated the rate of biofilm development, and bacterial levels on disinfected iron pipes exceeded those for chlorinated polyvinyl chloride pipes . The study showed that the iron pipe surface dramatically influenced the composition, activity, and disinfection resistance of biofilm bacteria.

Infect Control Hosp Epidemiol, 1999 Dec, 20(12), 798 - 805
Hospital characteristics associated with colonization of water systems by Legionella and risk of nosocomial legionnaires' disease: a cohort study of 15 hospitals; Kool JL et al.; OBJECTIVE: To investigate an increase in reports of legionnaires' disease by multiple hospitals in San Antonio, Texas, and to study risk factors for nosocomial transmission of legionnaires' disease and determinants for Legionella colonization of hospital hot-water systems . SETTING: The 16 largest hospitals in the cities of San Antonio, Temple, and Austin, Texas . DESIGN: Review of laboratory databases to identify patients with legionnaires' disease in the 3 years prior to the investigation and to determine the number of diagnostic tests for Legionella performed; measurement of hot-water temperature and chlorine concentration and culture of potable water for Legionella . Exact univariate calculations, Poisson regression, and linear regression were used to determine factors associated with water-system colonization and transmission of Legionella . RESULTS: Twelve cases of nosocomial legionnaires' disease were identified; eight of these occurred in 1996 . The rise in cases occurred shortly after physicians started requesting Legionella urinary antigen tests . Hospitals that frequently used Legionella urinary antigen tests tended to detect more cases of legionnaires' disease . Legionella was isolated from the water systems of 11 of 12 hospitals in San Antonio; the 12th had just experienced an outbreak of legionnaires' disease and had implemented control measures . Nosocomial legionellosis cases probably occurred in 5 hospitals . The number of nosocomial legionnaires' disease cases in each hospital correlated better with the proportion of water-system sites that tested positive for Legionella (P=.07) than with the concentration of Legionella bacteria in water samples (P=.23) . Hospitals in municipalities where the water treatment plant used monochloramine as a residual disinfectant (n=4) and the hospital that had implemented control measures were Legionella-free . The hot-water systems of all other hospitals (n=11) were colonized with Legionella . These were all supplied with municipal drinking water that contained free chlorine as a residual disinfectant . In these contaminated hospitals, the proportion of sites testing positive was inversely correlated with free residual chlorine concentration (P=.01) . In all hospitals, hot-water temperatures were too low to inhibit Legionella growth . CONCLUSIONS: The increase in reporting of nosocomial legionnaires' disease was attributable to increased use of urinary antigen tests; prior cases may have gone unrecognized . Risk of legionnaires' disease in hospital patients was better predicted by the proportion of water-system sites testing positive for Legionella than by the measured concentration of Legionella bacteria . Use of monochloramine by municipalities for residual drinking water disinfection may help prevent legionnaires' disease.

Nephrol News Issues . 1999 Jun;13(6):18, 23, 27.
Proper mechanisms for assuring disinfectant concentrations for use in hemodialysis; Arduino MJ; Testing for the presence or absence of chemical germicides in hemodialysis is a critical component to assure patient safety . It is necessary to verify early prepared solutions are being used and rinsed out of devices (water treatment systems, dialysis machines, hemodialyzers), and to make sure equipment is working properly to remove drinking water disinfectants . It is important to use tests and procedures that have FDA clearance for use specifically in hemodialysis or, in the case of chlorine, the recommended test for detecting residual free and total chlorine as referenced in the Standard Methods for the Analysis of Water and Wastewater . Products without specific labeling for dialysis should be avoided . Positive and negative controls should be included to validate testing.

Tohoku J Exp Med, 1999 Jul, 188(3), 217 - 25
Trace element levels in drinking water and the incidence of colorectal cancer; Kikuchi H et al.; We determined the levels of 15 elements in drinking water from 34 water treatment plants in Aomori Prefecture and studied how element levels relate to colorectal cancer incidence by district . Colorectal cancer incidence was calculated from the data of Aomori Colorectal Cancer Registry . Multiple regression analysis was performed by using age-adjusted incidences of rectal cancer and colon cancer by gender as object variables and each element level as an explanatory variable . The standardized partial regression coefficient was significant in gold (p < 0.01), magnesium (p < 0.01), selenium (p < 0.01) and tin (p < 0.05) for age-adjusted rectal cancer incidence in men as objective variable; in gold (p < 0.05), calcium (p < 0.01) and phosphorus (p < 0.01) with age-adjusted colon cancer incidence in men as the objective variable; and in sodium (p < 0.05), phosphorus (p < 0.05), tin (p < 0.05) and strontium (p < 0.01) with age-adjusted colon cancer incidence in women as the objective variable . These results confirm the need to further study trace elements in drinking water and food, and relationship to colorectal carcinogenesis.

Environ Health Perspect, 1999 Dec, 107(12), 975 - 84
Biological warfare agents as threats to potable water; Burrows WD et al.; Nearly all known biological warfare agents are intended for aerosol application . Although less effective as potable water threats, many are potentially capable of inflicting heavy casualties when ingested . Significant loss of mission capability can be anticipated even when complete recovery is possible . Properly maintained field army water purification equipment can counter this threat, but personnel responsible for the operation and maintenance of the equipment may be most at risk of exposure . Municipal water treatment facilities would be measurably less effective . Some replicating (infectious) agents and a few biotoxins are inactivated by chlorine disinfection; for others chlorine is ineffective or of unknown efficacy . This report assesses the state of our knowledge of agents as potable water threats and contemplates the consequences of intentional or collateral contamination of potable water supplies by 18 replicating agents and 9 biotoxins known or likely to be weaponized or otherwise used as threats.

Appl Environ Microbiol, 1999 Dec, 65(12), 5624 - 7
Molecular detection of Norwalk-like caliciviruses in sewage; Lodder WJ et al.; In this study, Norwalk-like virus (NLV) RNA was detected by reverse transcriptase PCR (RT-PCR) in sewage water concentrates . Sequence analysis of the RT-PCR products revealed identical sequences in stools of patients and related sewage samples . In 6 of 11 outbreak-unrelated follow-up samples, multiple NLV genotypes were present . Levels as high as 10(7) RNA-containing particles per liter were found . These data show that high loads of NLVs may be present in sewage and warrant further studies addressing the efficacy of NLV removal by sewage water treatment processes.

Kidney Int, 1999 Nov, 56(5), 1886 - 92
Increased serum strontium levels in dialysis patients: an epidemiological survey; Schrooten I et al.; BACKGROUND: We previously reported on increased bone strontium levels in dialysis patients with osteomalacia versus those presenting other types of renal osteodystrophy . A causal role of strontium in the development of osteomalacia was established in a chronic renal failure rat model . METHODS: To further elucidate the latter issue and to find out whether dialysis patients from particular centers/countries are at an increased risk for strontium accumulation, a worldwide multicenter study was established . In total, 834 patients from 34 dialysis centers in 23 countries were included . In each of the patients, a serum sample was taken for strontium determination, and water and dialysate samples were taken at the various steps of the water purification process . For each patient clinical data and for each center dialysis modalities were recorded . RESULTS: Strontium levels in serum of dialysis patients showed major differences between the various centers, ranging from mean values of 25 +/- 8 microgram/liter in the center with the lowest level up to 466 +/- 90 microgram/liter in the center with the highest concentration . It is of interest that these high levels were mainly found in developing countries . Furthermore, our data point toward a role of the final dialysate in the accumulation of the element, as indicated by the strong correlation (r = 0.74, P < 0.001) between mean serum and dialysate strontium levels . As the high tap water concentration of strontium was adequately reduced during the water purification process, contamination of the final dialysis fluid occurred by the addition of concentrates contaminated with strontium . Besides the dialysate, other factors, such as duration of dialysis, vitamin D supplements, or types of phosphate binders, played a less important role in the accumulation of the element . CONCLUSIONS: Data of this multicenter study indicate patients of particular dialysis centers to be at an increased risk for strontium accumulation, the clinical consequence of which is under current investigation.

Chirality, 1999, 11(10), 795 - 801
Enantiomeric composition of the polycyclic musks HHCB and AHTN in different aquatic species
Franke S, Meyer C, Heinzel N, Gatermann R, Huhnerfuss H, Rimkus G, Konig WA, Francke W.
Synthetic polycyclic musk fragrances are mainly represented by the compounds HHCB (Galaxolide(TM)) and AHTN (Tonalide(TM)) . Because of their volume of use and their bioaccumulation potential, there is concern with respect to their environmental safety . HHCB and AHTN are chiral compounds, and gas chromatography using modified cyclodextrins as chiral stationary phases coupled to high-resolution mass spectrometry enabled enantioselective analysis even under unfavorable matrix conditions . The gas chromatographic elution order of (4S,7RS)- and (4R,7RS)-HHCB was assigned using synthetic (4S, 7RS)-HHCB . Fish and mussels reared in a pond associated with a municipal waste water treatment plant and semipermeable membrane devices exposed in the pond were analyzed for HHCB and AHTN . The highest lipid concentrations of HHCB and AHTN were observed in mussels (Dreissena polymorpha), tench (Tinca tinca), and crucian carp (Carassius carassius) . Pronounced deviations in enantiomeric composition from racemic HHCB were observed in crucian carp and from racemic AHTN in tench . Correlations between lipid levels, enrichment, and enantioselective biotransformation of HHCB or AHTN were not seen . Selective biotransformation depended on both the compound and the species involved . The present study gives the first account of the enantiomeric composition of HHCB and AHTN in aquatic species . The lactone, 1,3,4,6,7,8-hexahydro-4,6,6,7,8, 8-hexamethylcyclopenta{g}-2-benzopyran-1-one, an oxidation product of HHCB, has been identified for the first time in environmental samples .

Med Trop (Mars), 1999, 59(2), 169 - 72
{Endemic cholera in Chad: a real public health problem}; Richard V et al.; At the present time, cholera epidemics have become annual, even seasonal, events in Chad . This review of data obtained from a Division of the Sanitation Information System in Chad was carried out to determine the epidemiological profile and natural course of cholera in Chad and to propose preventive measures within the country's means . The main findings were that cholera epidemics start at the junction between the dry and rainy season (March to June), that they last for six months, and that peak incidence occurs 4 to 6 weeks after the first reported cases . The mortality rate is approximately 5 p . 100 depending on time and place . Two foci were located: one at Logone-Gana (Chari-Baguiri) and the other at Fianga (Mayo-Kebbi) . These findings show that cholera is now endemic in Chad . A major implication of this study is that decentralized epidemiological surveillance should be set up with monitoring units located around endemic sites . Mortality could probably be lowered by better patient care at the beginning of the epidemic . Improvements in public hygiene, waste disposal, and water purification are needed.

Nephrol Dial Transplant, 1999 Oct, 14(10), 2433 - 7
Improved bacteriological surveillance of haemodialysis fluids: a comparison between Tryptic soy agar and Reasoner's 2A media; van der Linde K et al.; BACKGROUND: Accurate microbiological surveillance in haemodialysis centres is important as end-stage renal patients can suffer from pyrogenic reactions due to bacterial contamination of dialysis fluids . To evaluate the microbiological quality of haemodialysis fluids, special nutrient-poor culture techniques are necessary . Although the Association for the Advancement of Medical Instrumentation (AAMI) recommends Tryptic soy agar (TSA) as the standard agar, several studies have resulted in a general preference for Reasoner's 2A (R2A) agar, as it appeared to be more sensitive in demonstrating contamination of typical haemodialysis associated bacteria . In the Netherlands TSA is still used for culturing dialysate, while dialysis water is cultured on R2A . Therefore, the aims of our study were to evaluate bacterial yields of dialysis fluids on both media, and to qualify their use in routine microbiological monitoring within our haemodialysis centre . METHODS: Between April 1995 and March 1996, 229 samples of pre-treated and final purified dialysis water, and samples of dialysates were collected . The specimens were aseptically taken from the tap, various points of the reverse osmosis (RO) water-treatment system, and the effluent tubes of 32 bicarbonate haemodialysis machines . Samples of 0.1 ml were inoculated in duplicate on spread plates with TSA and R2A agars . After 10 days of incubation at 25+/-2 degrees C, the numbers of colonies were quantified . The ranges of spread were taken 0-100 and 0-200 colony-forming units per milliliter (c.f.u./ml) . RESULTS: The R2A agar had significantly higher colony counts than TSA agar for both dialysis water and dialysates . Considering 100 c.f.u./ml as the upper allowable bacterial limit for all dialysis fluids, microbiological non-compliance (bacterial growth) would be missed in 16% when using only TSA media (TSA < or =100 c.f.u./ml and R2A >100 c.f.u./ml), while this was 3% when using only R2A (TSA >100 c.f.u./ml and R2A < or =100 c.f.u./ml, P<0.0001) . Considering 200 c.f.u./ml as the upper limit, non-compliance would have been missed in 10% when using only TSA (TSA < or =200 c.f.u./ml and R2A >200 c.f.u./ml), and 2% when using R2A (TSA > 200 c.f.u./ml and R2A < or =200 c.f.u./ml, P = 0.0011) . CONCLUSIONS: Microbiological surveillance of haemodialysis fluids, including pre-treated dialysis water samples collected from RO treatment systems, can be performed more precisely with R2A media than TSA, when incubated at 25+/-2 degrees C for 10 days.

Can J Microbiol, 1999 Aug, 45(8), 709 - 15
Poor efficacy of residual chlorine disinfectant in drinking water to inactivate waterborne pathogens in distribution systems; Payment P; To evaluate the inactivating power of residual chlorine in a distribution system, test microorganisms (Escherichia coli, Clostridium perfringens, bacteriophage phi-X 170, and poliovirus type 1) were added to drinking water samples obtained from two water treatment plants and their distribution system . Except for Escherichia coli, microorganisms remained relatively unaffected in water from the distribution systems tested . When sewage was added to the water samples, indigenous thermotolerant coliforms were inactivated only when water was obtained from sites very close to the treatment plant and containing a high residual chlorine concentration . Clostridium perfringens was barely inactivated, suggesting that the most resistant pathogens such as Giardia lamblia, Cryptosporidium parvum, and human enteric viruses would not be inactivated . Our results suggest that the maintenance of a free residual concentration in a distribution system does not provide a significant inactivation of pathogens, could even mask events of contamination of the distribution, and thus would provide only a false sense of safety with little active protection of public health . Recent epidemiological studies that have suggested a significant waterborne level of endemic gastrointestinal illness could then be explained by undetected intrusions in the distribution system, intrusions resulting in the infection of a small number of individuals without eliciting an outbreak situation.

J Chromatogr A, 1999 Aug 27, 854(1-2), 163 - 73
Detection and identification of sulphonamide drugs in municipal waste water by liquid chromatography coupled with electrospray ionisation tandem mass spectrometry; Hartig C et al.; High-performance liquid chromatography coupled with positive-ion electrospray ionisation tandem mass spectrometry was used for the determination and confirmation of 13 sulphonamide drugs in environmental water samples in the low ng/L-range . Enrichment with concentration factors of 130-670 was performed by solid phase extraction, achieving recoveries of 50 to 90% . After gradient elution HPLC, detection and quantification was performed using selected reaction monitoring (SRM) with limits of detection between 0.2 and 3.7 microg/L . Confirmation was obtained by either SRM transitions of collision induced dissociation reactions or daughter ion mass spectra . Primary and secondary effluents of municipal waste water treatment plants and different surface waters were examined . The compounds sulphamethoxazole and sulphadiazine were detected and confirmed with concentrations ranging between 30-2000 ng/L and 10-100 ng/L, respectively . The compound sulphamethizole was detected in low amounts but could not be positively confirmed.

Blood Purif, 1999, 17(4), 187 - 98
Trace elements in end-stage renal disease . 2 . Clinical implication of trace elements; Zima T et al.; For human beings trace elements are essential nutrients with a gamut of functions . They are for instance indispensable components of many enzymes, so they have some regulatory functions and they may affect immune reactions and free radical generation . Abnormalities of trace elements are primarily the result of uremia, and they may be further modified and sometimes greatly exacerbated by the dialysis procedure . The role of trace elements in hemodialysis (HD) patients has not yet been fully characterized . To prevent some complications in chronic HD patients, it is very important to regulate the levels of trace elements by adequate water treatment . Reverse osmosis is able to prevent the accumulation of the majority of trace elements in the patients . Zinc supplementation may be recommended for patients with proven zinc deficiency, but for all chronic renal failure patients it is questionable . Selenium deficiency is to be suspected in dialyzed patients and selenium supplementation may be beneficial (increasing glutathione peroxidase activity, cardioprotective effect, immunostimulatory properties) for chronic renal failure patients . Supplementation with a trace element may be indicated when its depletion was unequivocally documented and when there is evidence of the positive effects of this element on the quality of life of the dialyzed patients.

Blood Purif, 1999, 17(4), 182 - 6
Trace elements in end-stage renal disease . 1 . Methodological aspects and the influence of water treatment and dialysis equipment; Zima T et al.; For human beings trace elements are essential nutrients with a gamut of functions . They are for instance indispensable components of many enzymes, so they have some regulatory functions and they may affect immune reactions and free radical generation . Altered blood levels of different trace elements have been described in patients with advanced renal failure and especially in those treated by different kinds of renal replacement therapy . Altered renal function may result in impaired renal excretion of trace elements and their accumulation or depletion in the body . The dialysate concentrate and water used for preparing the dialysate may be an important source of the accumulation or depletion of trace elements in dialyzed patients . The gain or loss of trace elements during dialysis depends on the gradient between the ultrafiltrable fraction of a particular element in serum and its concentration in the dialysis fluid, and also on the type and permeability of the dialysis membrane . There are some methodological problems concerning the handling and storing of blood samples and measurement techniques leading to the rather inconsistent results of different studies concerning trace elements in renal disease . Geographical variations and environmental contamination of soil and water and different dietary habits may significantly influence trace elements in these patients . The abnormalities of trace elements are primarily the result of uremia, and they may be further modified and sometimes greatly exacerbated by the dialysis procedure.

J Food Prot, 1999 Sep, 62(9), 1071 - 87
Application of ozone for enhancing the microbiological safety and quality of foods: a review; Kim JG et al.; Ozone (O3) is a strong antimicrobial agent with numerous potential applications in the food industry . High reactivity, penetrability, and spontaneous decomposition to a nontoxic product (i.e., O2) make ozone a viable disinfectant for ensuring the microbiological safety of food products . Ozone has been used for decades in many countries and recently, the generally recognized as safe (GRAS) status of this gas has been reaffirmed in the United States . Ozone, in the gaseous or aqueous phases, is effective against the majority of microorganisms tested by numerous research groups . Relatively low concentrations of ozone and short contact time are sufficient to inactivate bacteria, molds, yeasts, parasites, and viruses . However, rates of inactivation are greater in ozone demand-free systems than when the medium contains oxidizable organic substances . Susceptibility of microorganisms to ozone also varies with the physiological state of the culture, pH of the medium, temperature, humidity, and presence of additives (e.g., acids, surfactants, and sugars) . Ozone applications in the food industry are mostly related to decontamination of product surface and water treatment . Ozone has been used with mixed success to inactivate contaminant microflora on meat, poultry, eggs, fish, fruits, vegetables, and dry foods . The gas also is useful in detoxification and elimination of mycotoxins and pesticide residues from some agricultural products . Excessive use of ozone, however, may cause oxidation of some ingredients on food surface . This usually results in discoloration and deterioration of food flavor . Additional research is needed to elucidate the kinetics and mechanisms of microbial inactivation by ozone and to optimize its use in food applications.

Appl Environ Microbiol, 1999 Sep, 65(9), 4276 - 9
Efficacy of electrolyzed oxidizing water for inactivating Escherichia coli O157:H7, Salmonella enteritidis, and Listeria monocytogenes; Venkitanarayanan KS et al.; The efficacy of electrolyzed oxidizing water for inactivating Escherichia coli O157:H7, Salmonella enteritidis, and Listeria monocytogenes was evaluated . A five-strain mixture of E . coli O157:H7, S . enteritidis, or L . monocytogenes of approximately 10(8) CFU/ml was inoculated in 9 ml of electrolyzed oxidizing water (treatment) or 9 ml of sterile, deionized water (control) and incubated at 4 or 23 degrees C for 0, 5, 10, and 15 min; at 35 degrees C for 0, 2, 4, and 6 min; or at 45 degrees C for 0, 1, 3, and 5 min . The surviving population of each pathogen at each sampling time was determined on tryptic soy agar . At 4 or 23 degrees C, an exposure time of 5 min reduced the populations of all three pathogens in the treatment samples by approximately 7 log CFU/ml, with complete inactivation by 10 min of exposure . A reduction of >/=7 log CFU/ml in the levels of the three pathogens occurred in the treatment samples incubated for 1 min at 45 degrees C or for 2 min at 35 degrees C . The bacterial counts of all three pathogens in control samples remained the same throughout the incubation at all four temperatures . Results indicate that electrolyzed oxidizing water may be a useful disinfectant, but appropriate applications need to be validated.

Anal Biochem, 1999 Sep 10, 273(2), 156 - 62
Direct detection of proteins adsorbed on synthetic materials by matrix-assisted laser desorption ionization-mass spectrometry; Kingshott P et al.; The irreversible accumulation of biological material on synthetic surfaces ("biofouling") adversely affects for instance contact lenses, implantable biomedical devices, biosensors, water purification, transport and storage systems, and marine structures . It is shown here that proteins adsorbed on contact lenses can be detected directly, rapidly, and conveniently, with high sensitivity, by matrix-assisted laser desorption ionization (MALDI)-mass spectrometry . This new approach allows detection of minor (and major) proteinaceous constituents of biofouled layers on samples retrieved from clinical usage and in vitro protein adsorption studies, at levels substantially below monolayer coverage . Identification of the detected biological molecules can be done by comparison of the detected mass peaks with known protein molecular masses or with spectra recorded of pure compounds or by separate biochemical assays . The MALDI mass spectra recorded on different contact lenses contain peaks assignable to lysozyme and a number of smaller proteins . Such sensitive characterization of the early stages of biofouling enhances the understanding of protein/materials interactions and assists in designing guided strategies toward control of biological adsorption processes .

Chemosphere, 1999 Oct, 39(8), 1309 - 15
Rapid treatment of water contamined with atrazine and parathion with zero-valent iron; Ghauch A et al.; The utility of fine-grained iron metal in the remediation of water contamined with Atrazine and Parathion was investigated . Batch procedures under water treatment conditions (ambient temperature and pH of approximately 7) indicated that these pesticides degrade rapidly in the presence of iron powder (40-60 mesh, 40 g/l) . The decline in the concentration of pesticide was monitored by HPLC . Experiments with unbuffered solutions showed a steady increase in pH values during the reactions . Therefore, experiments were run in buffered solutions . Different buffered solutions resulted in different degradation rates indicating that the buffer plays an important role in enhancing the degradation process . Tests were also performed on an industrial effluent solution containing a variety of pesticides . Although the products of degradation were not characterized, our HPLC results indicated the disappearance of all the parent pollutants.

Rev Argent Microbiol, 1999 Apr-Jun, 31(2), 97 - 105
{Cryptosporidium and water}; Lerman de Abramovich B et al.; During the last years, cryptosporidiosis has been recognized as an important cause of diarrheal disease . According to different references, water has been an important vehicle responsible for the transmission in many epidemic outbreaks . The high number of oocysts eliminated by human and animal hosts, as well as low infectious dose and its resistance to desinfectants are some factors which contribute to the infectious risk . It has been also pointed that bacteriologically acceptable water may contain parasites . In order to minimize such risks, it is desirable to protect the water supplies and to use multiple barriers (coagulation, sedimentation and filtration) in drinking water treatment . The aim of this work is to provide information about the different aspects conditioning the presence of Cryptosporidium in drinking water.

Zentralbl Hyg Umweltmed, 1999 Jun, 202(1), 61 - 75
Chlorate as an inorganic disinfection by product in swimming pools; Erdinger L et al.; Chlorate and chlorite concentrations were determined in water samples taken from 33 swimming pools . In the pools under investigation, disinfection of the water is carried out either by gaseous chlorine (n = 14) or hypochlorite solution in conjunction with flocculation and sand filtration . A number of the pools also use ozone treatment to augment the disinfection process . Chlorite was not detectable in any of the samples (detection limit 1 mg/l) . High concentrations of chlorate were detected in samples from a number of the pools; in one case as high as 40 mg/l . Higher chlorate concentrations were found to be associated with those pools using hypochlorite solution as a disinfecting agent . In contrast, relatively low chlorate concentrations were found in pools treated with gaseous chlorine . In order to elucidate any relationship between the chlorate content of pool water and that of the respective hypochlorite stock solution, chlorate and bromate concentrations were determined in the hypochlorite stock solutions of nine pools . Bromate concentration in the stock solutions were not found to exceed 1.2 g/l, chlorate was measured in concentrations of up to 44.5 g/l . The additional use of ozone as part of the water purification process appears to have no significant influence on chlorate concentration . Chlorate has no bactericidal properties and does not interfere with the measurement of certain parameters relevant to hygiene in swimming pools such as free and combined chlorine, pH or redox potential . At present, the effects of high chlorate concentrations in swimming pool water are unclear . Our initial investigations indicate that chlorate has no cytotoxic (Neutral-Red assay) or irritating properties (HET-CAM assay) . However, both chlorate and chlorite are known to interfere with the haematopoetic system . In Germany, the MCL for chlorite in drinking water is 0.2 mg/l . It is therefore strongly recommended that measures should be taken to reduce chlorate concentrations in swimming pool water.

J Expo Anal Environ Epidemiol, 1999 May-Jun, 9(3), 192 - 9
Assessment of disinfection by-products in drinking water in Korea; Shin D et al.; The main purpose of applying the chlorination process during water treatment is for disinfection . Research results, however, indicate that disinfection byproducts (DBPs) including trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), haloketones (HKs), and chloropicrin (CP) can be produced by the chlorination process . Some of these DBPs are known to be potential human carcinogens . This 3-year project is designed to establish a standard analysis procedure for DBPs in drinking water of this country and investigate the distribution and sources of specific DBPs . The occurrence level of DBPs in drinking water was below 50 micrograms/l in most cases . THMs in plant effluent accounted for 60% of all DBPs measured, whereas HAAs accounted for 20%, HANs 12%, HKs 5% and CP 3% . Chloroform was found to be the major THMs compound (77%), followed by bromodichloromethane (BDCM, 18%) and bromoform (BF, 3%) . The concentration of DBPs formed in distribution systems increased from those detected in plant effluent . Comparison of humic acid and sewage as precursors for THMs formation showed that humic acid was the major THMs precursor . Results would play an important role in exposure assessment as a part of the risk assessment process, and would give basic information for establishment of DBPs reduction and management procedures.

J Toxicol Environ Health A, 1999 Jul 9, 57(5), 357 - 68
Effect of enterohepatic circulation on the pharmacokinetics of chloral hydrate and its metabolites in F344 rats; Merdink JL et al.; Chloral hydrate (CH) is a commonly found disinfection by-product in water purification, a metabolite of trichloroethylene, and a sedative/hypnotic drug . CH and two of its reported metabolites, trichloroacetic acid (TCA) and dichloroacetic acid (DCA), are hepatocarcinogenic in mice . Another metabolite of CH, trichloroethanol (TCE), is also metabolized into TCA, and the enterohepatic circulation (EHC) of TCE maintains a pool of metabolite for the eventual production of TCA . To gain insight on the effects of EHC on the kinetics of CH and on the formation of TCA and DCA, dual cannulated F344 rats were infused with 12, 48, or 192 mg/kg of CH and the blood, bile, urine, and feces were collected over a 48-h period . CH was cleared rapidly (>3000 ml/h/kg) and displayed biphasic elimination kinetics, with the first phase being elimination of the dose and the second phase exhibiting formation rate-limited kinetics relative to its TCE metabolite . The effects of EHC on metabolite kinetics were only significant at the highest dose, resulting in a 44% and 17% decrease in the area under the curve (AUC) of TCA and TCE, respectively . The renal clearance of CH, free TCE (f-TCE), and TCA of 2, 2.7, and 38 ml/h/kg, respectively, indicates an efficient reabsorption mechanism for all of these small chlorinated compounds . DCA was detected at only trace levels (<2 microM) as a metabolite of CH, TCA, or TCE.

Syst Appl Microbiol, 1999 May, 22(2), 197 - 204
Defluvibacter lusatiae gen . nov., sp . nov., a new chlorohenol-degrading member of the alpha-2 subgroup of proteobacteria; Fritsche K et al.; The two Gram-negative bacterial strains S1 and S4 were isolated from activated sludge of an industrial waste water treatment plant and exhibited a stable capability to degrade 2,4-dichlorophenol, 4-chloro-2-methylphenol, 4-chlorophenol and phenol . The cells were short rods with a polar flagellum, being mesophilic, strictly aerobic, oxidase-positive, and chemoorganotrophic . They utilized a range of amino acids, but only a restricted number of carbohydrates . Reassociation experiments with DNA from strains S1 and S4 revealed high interstrain similarity, indicating, that both strains belong to the same species . The phylogenetic position was determined by comparison of the almost complete 16S rDNA sequence of strain S1 with sequences of related bacteria . Strain S1 clustered with members of the alpha-2 subgroup of the Proteobacteria by forming a separate lineage within the radiation of Mesorhizobium, Phyllobacterium and Sinorhizobium . Both strains can be differentiated from members of related taxa by a set of physiological and chemotaxonomic properties including the ability to grow with norvaline, L-tryptophan, putrescine, glutarate and malonate, and by the presence of spermidine as major polyamine and of 12:0 3OH as fatty acid . Strain S1 is described as type strain of a new species and assigned to a new genus with the proposed name Defluvibacter lusatiae.

Can J Microbiol, 1998 Dec, 44(12), 1154 - 60
Aging of Cryptosporidium parvum oocysts in river water and their susceptibility to disinfection by chlorine and monochloramine; Chauret C et al.; Cryptosporidium parvum oocysts were aged in waters from both the St . Lawrence River and the Ottawa River . In situ survival experiments were carried out by incubating the oocysts in either dialysis cassettes or microtubes floated into an overflow tank . A significant portion of the oocysts survived in the test waters for several weeks . Oocyst survival in the St . Lawrence River was better in membrane-filtered (0.2 microm-pore diameter) water than in unfiltered water, suggesting that biological antagonism may play a role in the environmental fate of the parasite . Oocysts aged in river waters under in situ conditions and control oocysts kept refrigerated in synthetic water (100 ppm as CaCO3); pH 7.0) were subjected to the same disinfection protocol . Aged oocysts were at least as resistant as, if not more resistant than, the control oocysts to disinfection . This indicates that the oocysts surviving in the water environment may be just as difficult to inactivate by potable water disinfection as freshly shed oocysts . Therefore, water treatment should not be based on the assumption that environmental oocysts may be more easily inactivated than freshly shed oocysts . First-order kinetics die-off rates varied from one river to another (from 0.013 to 0.039 log(10).day(-1)) and from one experiment to another with water from the same river collected at different times . Calculation of the die-off rates based on either in vitro excystation or in vitro excystation in combination with total counts (overall die-off rates) showed that the assessment of oocyst viability by microscopic methods must account for the total oocyst loss observed during long-term inactivation assays of river waters.

Can J Microbiol, 1998 Dec, 44(12), 1142 - 7
Isolation of a methanogenic bacterium, Methanosarcina sp . strain FR, for its ability to degrade high concentration of perchloroethylene; Cabirol N et al.; Tetrachloroethylene (PCE) is a toxic compound essentially used as a degreasing and dry-cleaning solvent . A methanogenic and sulfate-reducing consortium that dechlorinates and mineralizes high concentrations of PCE was derived from anaerobically digested sludge obtained from a waste water treatment plant (Bourg-en-Bresse, France) . A methanogenic bacterium, strain FR, was isolated from this acclimated consortium . On the basis of morphological and physiological characteristics, strain FR was classified in the genus of Methanosarcina . Phylogeny analysis with the 16S rRNA gene sequence revealed that strain FR is highly related to Methanosarcina mazei and Methanosarcina frisia (99.6 and 99.5% identity, respectively) . High concentrations (50-87 microM) of PCE were completely dechlorinated by strain FR cultures at the rate of 76 nM-mg protein(-1).day(-1) . PCE dechlorination produced a nonidentified compound . The tracer experiments with {13C}PCE revealed that the product was nonchlorinated . Dechlorination of PCE to trichloroethylene was still active in the presence of boiled cell extract of the strain FR . However, no further dechlorination was observed . This result suggests that a cofactor rather than an enzymatic system is responsible for the first dechlorination of PCE . Dechlorination-active fractions purified from cell extracts on a XAD-4 column revealed the presence of F(420), F(430), and cobamides cofactors . This is the first report of the isolation of a methanogenic bacterium with the ability to dechlorinate high concentrations of PCE to a nonchlorinated product.

J Appl Psychol, 1999 Jun, 84(3), 456 - 63
Production uncertainty as a contextual moderator of employee reactions to job design; Wright BM et al.; A number of authors in the job design field have proposed production uncertainty, the degree to which a qualified incumbent faces unexpected problems in the course of job performance, as a possible moderator of the effectiveness of job design . However, empirical support for this view is limited and has not been explicitly recognized within mainstream job design theory . This study of production operators in a waste water treatment setting provides further empirical support for production uncertainty as a contextual variable influencing job design outcomes, demonstrating that the relationship between job control and affective outcomes (job satisfaction and intrinsic motivation) varies with the level of production uncertainty.

N Z Med J, 1999 May 14, 112(1087), 158 - 61
Health advice given by general practitioners for travellers from New Zealand; Leggat PA et al.; AIMS: To investigate where general practitioners (GP's) in New Zealand view travel health advice best given and where they refer for this advice, the prevalence of travel health advice reported to be given, and the prevalence of written advice, including a doctor's letter . METHOD: This was a descriptive cross-sectional study, using self-report questionnaires, sent to 400 GPs randomly selected from the register of the New Zealand Medical Council . RESULTS: Three hundred and thirty-two GPs (83%) responded . Most GPs reported that they saw travel medicine as best practised in general practice (241/308, 78%) or in a combination of locations, usually including general practice (28/308, 9%) . Most GPs (223/308, 72%) did not refer travellers for travel health advice . Health advice concerning malaria (310/310, 100%), immunisation (309/310, 100%), travellers' diarrhoea (296/305, 97%), insect avoidance (287/ 299, 96%), sexually transmitted diseases/human immunodeficiency virus (233/283, 82%), water purification (235/293, 80%) and other areas (35/75, 47%) was given . Written advice was usually given by 23% of GPs (69/302) . Written advice was significantly more likely to be provided by those GPs with an interest in travel medicine (chi2=5.67, df=1, p<0.005), experience in tropical medicine/developing countries (chi2=6.69, df=1, p<0.001), a policy on travel medicine (chi2=21.4, df=1, p<0.001), a written policy on travel medicine (chi2=302.0, df=1, p<0.001), who saw a higher number of travellers per week (t=-2.51, df=296, p<0.05) and who saw a significantly higher proportion of patients who were travellers (t=-3.27, df=-295, p=0.001) . Almost all GPs (303/310, 98%) reported giving their travelling patients a doctor's letter at least sometimes but only 7% (23/310) always gave travellers a doctor's letter . GPs with training in travel medicine/related area were significantly more likely to provide travellers with a doctor's letter (chi=11.61, df=3, p<0.01) . CONCLUSIONS: This study confirmed that GPs in New Zealand see travel health advice as best given in general practice . Travel health advice, as recommended by New Zealand guidelines, should continue to be given . With limited time in general practice to advise travellers, GPs should also consider giving written advice, including a doctor's letter, more often . Epidemiological and specialist support by public health units and commercial groups, continuing medical education and training in travel medicine for GPs are among the major considerations . Further studies are needed concerning the adequacy and currency of destination-specific advice for travellers.

J Toxicol Environ Health A, 1999 Jun 11, 57(3), 149 - 60
The prevalence of Giardia and Cryptosporidium in Taiwan water supplies; Hsu BM et al.; Giardia and Cryptosporidium have emerged as waterborne pathogens of concern . Thirty-one water samples were collected from nine potable water treatment plants in Taiwan and investigated for the presence of Giardia cysts and Cryptosporidium oocysts . The immunofluorescence assay was used for the simultaneous detection of cysts and oocysts . The frequency of occurrence of cysts was 77.8% for Giardia and 72.2% for Cryptosporidium in 18 raw water samples . Ten out of 13 samples collected from treated water samples showed the presence of cysts, while in 5 out of 13 treated water samples oocysts were detected . The risk assessment for adverse human effects arising from the presence of cysts and oocysts indicates the possibility of waterborne transmission of Giardia and Cryptosporidium infection in Taiwan if water is not adequately treated.

Med Tekh, 1999 Mar-Apr, (2), 21 - 5
{Water purification for hemodialysis}; Eventov VL et al.; An electrodialysis system has been designed to purify water . It comprises two units: a preliminary preparation unit and an electrodialysis one . The system consists of columns containing zeolite, activated carbon, and ion-exchange resins . Zeolite makes water free from mechanical impurities and iron, activated carbon adsorbs organic matter and chlorine ions, ion-exchange resins soften water . The electrodialysis unit is noted for its original design . Mathematical simulation has allowed the authors to optimize the design and to make a block that makes the process continuous without repolarization, which can decant the minimum levels of salt concentrates, thus decreasing energy supply to 2 W per liter . The unit is made as a pressure filter design having the platinum-titanium electrodes and membranes MK-40 and MK-45 made in Russia . The system operates automatically . Its all components are made in Russia.

Eur J Endocrinol, 1999 May, 140(5), 400 - 3
Iodine in drinking water varies by more than 100-fold in Denmark . Importance for iodine content of infant formulas; Pedersen KM et al.; The iodine intake level of the population is of major importance for the occurrence of thyroid disorders in an area . The aim of the present study was to evaluate the importance of drinking water iodine content for the known regional differences in iodine intake in Denmark and for the iodine content of infant formulas . Iodine in tap water obtained from 55 different locations in Denmark varied from <1.0 to 139 microg/l . In general the iodine content was low in Jutland (median 4.1 microg/l) with higher values on Sealand (23 microg/l) and other islands . Preparation of coffee or tea did not reduce the iodine content of tap water with a high initial iodine concentration . A statistically significant correlation was found between tap water iodine content today and the urinary iodine excretion measured in 41 towns in 1967 (r=0.68, P<0.001) . The correlation corresponded to a basic urinary iodine excretion in Denmark of 43 microg/24h excluding iodine in water and a daily water intake of 1.7 l . The iodine content of infant formulas prepared by addition of demineralized water varied from 37 to 138 microg/l (median 57 microg/l, n=18) . Hence the final iodine content would depend heavily on the source of water used for preparation . We found that iodine in tap water was a major determinant of regional differences in iodine intake in Denmark . Changes in water supply and possibly water purification methods may influence the population iodine intake level and the occurrence of thyroid disorders.

Rev Epidemiol Sante Publique, 1999 Mar, 47(1), 61 - 73
{Waterborne microbiological risk assessment: a state of the art and perspectives}; Gofti L et al.; Microbiological contamination is the most common threat related to drinking water . In developed countries, the current health system provides a good level of protection . However, some facts point out the need to develop further tools for better management of the waterborne risk . Several outbreaks have occurred in the United-States in the past decade . They were most often caused by tap water contamination associated with parasites and viruses, despite good compliance of the water treatment procedures . The chemical risk assessment methodology set up at the end of the 70's can now be applied for microbiological risks . This approach allowed the US authorities to improve their control on waterborne infection risks . Although limited, surveillance data suggest that to date . France has not encountered such outbreaks . However, the baselines and principles of risk management in that area should be also be optimized and updated . This work underlines the limits of the current risk management system . A literature review on microbiological risk assessment is first presented . Applications of this methodology are then commented, advantages and limits of the microbiological risk assessment approach in France are discussed.

Nephrol Dial Transplant, 1999 Mar, 14(3), 666 - 75
Quality of water used for haemodialysis: bacteriological and chemical parameters; Vorbeck-Meister I et al.; BACKGROUND: The bacterial and chemical contamination of dialysate fluids are important problems in haemodialysis therapy and may be caused by the water used for dialysate preparation . METHODS: We performed a survey of the microbiological and chemical quality of the water used in seven dialysis wards . Special attention was paid to the effects of each water treatment step, for example ion exchange, reverse osmosis and UV disinfection, on the number of bacteria (measured as colony forming units, CFU), the amount of endotoxin (endotoxin units, EU) and various chemical parameters, the main focus being on calcium, magnesium, sulphate, aluminium and heavy metals . RESULTS: CFU values exceeding the European Pharmacopeia value, determined at an incubation temperature of 22 degrees C, were found in the samples of raw water (20.0%, n=25), after ion exchange (66.7%, n=12), after reverse osmosis (33.3%, n=18) and also in samples of the dialysis water taken at the inlets (12.5%, n=40) and outlets (50.0%, n=18) of the machines . Whereas all raw water samples from the wards showed high mean values for endotoxin (0.56-9.10 EU/ml) and the endotoxin levels were often enhanced after ion exchange (0.13- >9.49 EU/ml), treatment by reverse osmosis led to a satisfactory decrease in endotoxin in all samples (<0.03 EU/ml) . Sufficient reductions in calcium, magnesium and sulphate could only be achieved by the combined application of ion exchange and reverse osmosis . Mercury contamination was observed in the samples after ion exchange at three treatment plants, this was possibly caused by polluted regenerants . Increased amounts of aluminium, copper and zinc were found in water samples from different sites in the treatment systems and were caused by materials in contact with the water . CONCLUSIONS: A sufficient chemical water purification treatment system should consist of ion exchange and reverse osmosis . Attention has to be paid to the suitability of materials in contact with the water and of the chemicals used, for example regenerants or corrosion inhibitors . From the microbiological point of view, a safety UV disinfection step in the water-treatment system is favourable . To avoid bacterial recontamination periodic cleaning and disinfecting of the water-treatment and distribution systems, as well as the dialysis machine are essential . There is the need for complete guidelines regarding dialysis water that include all relevant chemical and microbiological parameters . Based on this standard, periodic examination of the water after each treatment step has to be performed.

Chemosphere, 1999 Apr, 38(10), 2247 - 62
Assessment of organic contaminant fate in waste water treatment plants . I: Selected compounds and physicochemical properties; Alcock RE et al.; An extensive and comprehensive literature review has been conducted for compounds which we hypothesise could be present in sludge and maintain their integrity following application to agricultural land . The following compounds have been selected for review; chlorinated paraffins, quintozene, brominated diphenyl ethers, polychlorinated naphthalenes, polydimethylsiloxanes, chloronitrobenzenes, and a range of biologically active and pharmaceutical compounds . All have received interest as a result of their persistence and/or toxicity in environmental media . Physicochemical property information has also been compiled and/or calculated . In this way, an accompanying paper will attempt to predict compound fate in waste water treatment plants (WWTPs) and assess likely transfers from soil/plants to grazing livestock . These papers describe a first attempt to predict the fate of these classes of compounds in the environment and prioritise those of greatest concern.

Epidemiol Infect, 1999 Feb, 122(1), 83 - 90
Diarrhoea prevention in Bolivia through point-of-use water treatment and safe storage: a promising new strategy; Quick RE et al.; A novel water quality intervention that consists of point-of-use water disinfection, safe storage and community education was field tested in Bolivia . A total of 127 households in two periurban communities were randomized into intervention and control groups, surveyed and the intervention was distributed . Monthly water quality testing and weekly diarrhoea surveillance were conducted . Over a 5-month period, intervention households had 44% fewer diarrhoea episodes than control households (P = 0.002) . Infants < 1 year old (P = 0.05) and children 5-14 years old (P = 0.01) in intervention households had significantly less diarrhoea than control children . Campylobacter was less commonly isolated from intervention than control patients (P = 0.02) . Stored water in intervention households was less contaminated with Escherichia coli than stored water in control households (P < 0.0001) . Intervention households exhibited less E . coli contamination of stored water and less diarrhoea than control households . This promising new strategy may have broad applicability for waterborne disease prevention.

Environ Res, 1999 Feb, 80(2 Pt 1), 127 - 31
Genotoxicity of drinking water from Chao Lake; Liu Q et al.; Genotoxic activity appears to originate primarily from reactions of chlorine with humic substances in the source waters . Comparisons of extracts of settled versus chlorinated water have confirmed that chlorinating during water treatment produces mutagenic activity in the mutagenicity tests . Present work on XAD-2 extracts of raw, chlorinated (treated), and settled water from the Chao Lake region of China has involved a battery of mutagenicity assays for various genetic endpoints: the Salmonella test, the sister-chromatid exchange (SCE) induction in Chinese hamster lung (CHL) cells, and the micronucleus (MN) induction in the peripheral blood erythrocytes of silver carp . Extracts of raw and treated water but not the settled water are mutagenic in the Salmonella assay . On the other hand, extracts of three water samples show activity in the SCE and MN assays, especially the raw and treated water . These data show that contamination and chlorinating contribute mutagens to drinking water and suggest that the mammalian assays may be more sensitive for detecting mutagenicity in aquatic environment than the Salmonella test .

Hum Reprod, 1998 Dec, 13 Suppl 4, 166 - 72
The importance of water quality for media preparation; Wiemer KE et al.; The variability in pregnancy rates achieved among in-vitro fertilization (IVF) clinics may be partially attributable to the disparate quality of the water used in the preparation of culture media . The removal of contaminants in the water is of paramount importance since water constitutes the predominant component in any media formulation . To assist in the selection, operation and maintenance of a water purification system, the level of contaminants must be carefully monitored . Conductivity and resistance are used to measure the purity of natural and ultrapure water respectively . Feed water is analysed by an assortment of direct chemical means to determine the necessary system filtration steps . In general, high quality water can be produced by combined reverse osmosis and electrodeionization of treated tap water . Processed water is supplied to an ultrapure water system to provide final polished water . A detailed water processing protocol is presented along with quality assurance guidelines to ensure the consistent production of high quality ultrapure water suitable for in-vitro human embryo culture.

Am J Bot . 1999 Mar;86(3):367.
Effects of environmental factors on development of wood; Arnold DH et al.; This research tested the hypothesis that environmental factors (light, water, and nutrient levels) affect wood development . Specimens were placed in treatments of low, medium, or high levels of light, water, nitrogen, or phosphorus for one year . Control plants received medium levels of all factors, while experimental plants received medium levels of all factors except the experimental factor; for example, "high light" treatment consisted of high light but medium levels of water, nitrogen, and phosphorus . Some character changes seen in Cereus peruvianus were a reduction in mean vessel diameter and shoot elongation as a result of low nitrogen and low phosphorus treatments and a reduction in mean vessel density due to low light; high water induced broader vessels and greater shoot elongation . In Cereus tetragonus, low water treatment caused a reduction in mean vessel diameter, and high nitrogen decreased the amount of wood produced . Whereas all characters studied showed a significant correlation with at least one treatment in one species, few characters responded similarly between species . Estimated specific conductivity of wood could be altered by treatments affecting either vessel density or vessel diameter strongly or by treatments affecting both diameter and density weakly . Under the conditions tested, wood structure was stable but estimated conducting capacity was more flexible.

Chemosphere, 1999 Mar, 38(6), 1461 - 8
Degradation of polydimethylsiloxane fluids in the environment--a review; Griessbach EF et al.; Due to their insolubility in water and high adsorption coefficient, liquid polydimethylsiloxanes (PDMS) discharged as effluent will adsorb to particulate matter and, therefore, will become a component of sewage sludge during waste water treatment . The subsequent environmental fate of PDMS will depend on the fate of the sludge . Due to increasing practices of soil amendment with sewage sludge the principal environmental compartment receiving PDMS fluids is the soil . Degradation of PDMS is a common process taking place in many different types of soils . It occurs through a unique combination of environmental degradation processes . Initial hydrolysis of PDMS is catalysed by clay minerals, the principal component of soil . The primary hydrolysis product, dimethylsilanediol (DMSD), is then either biodegraded, or evaporated into the atmosphere, where it is subsequently oxidised in the presence of sunlight . The end products in both cases are expected to be CO2, SiO2 and H2O.

Med Lav, 1998 Sep-Oct, 89(5), 393 - 403
{An epidemiological study of a group of workers employed in the maintenance of a sewer network and of urban waste water treatment plants}; Salano R et al.; The paper reports the results of a study on occupational risks of a group of sewage workers of the city of Genoa vs . a control group of nonexposed subjects; the first group was divided into three subgroups according to the job characteristics . After bibliographical research on the topic, a specific questionnaire was used to analyse individual symptoms . Clinical examinations, blood and respiratory tests were also performed . The statistical analysis was performed by evaluating F test for differences between parametric measures and the relative risk for non-parametric findings . The relative risk of alterations in respiratory function (both instrumental and clinical findings) was increased among the water treatment workers . The average platelets count in the exposed workers appeared to be significantly reduced compared to non-exposed subjects although both were within the normal limits . There was non evidence of an increased prevalence of positive A hepatitis markers in the exposed workers.

J Appl Microbiol, 1999 Jan, 86(1), 168 - 73
Note: susceptibility to chlorine of Aeromonas hydrophila strains; Massa S et al.; The susceptibility of five Aeromonas hydrophila strains and one Escherichia coli strain to chlorine was studied under carefully controlled laboratory conditions . Of the Aer . hydrophila strains, two were from untreated water, two from tap water (immediately downstream of a water treatment plant) and one from the DSM collection . The study included disinfectant concentration (0.1, 0.2 and 0.5 mg l-1), pH (6, 7 and 8) and temperature (4, 21 and 32 degrees C) as controlled variables . The results indicated that the untreated water strains, the DSM strain and the E . coli strain were inactivated within 1 min of chlorine treatment . The strains from chlorinated water (TW11 and TW27) showed a different susceptibility to chlorine disinfection, the rate of inactivation being greater at pH6 than at pH8 for both strains . Under the standard conditions of temperature 21 degrees C, pH7 and chlorine concentration 0.2 mg l-1, an increase or decrease of approximately 1 log unit in the number of bacteria did not affect the kill rate of the strains TW11 and TW27.

Sci Total Environ, 1999 Jan 12, 225(1-2), 101 - 8
Analysis and occurrence of estrogenic hormones and their glucuronides in surface water and waste water in The Netherlands; Belfroid AC et al.; An analytical procedure was developed that enables routine analysis of four estrogenic hormones in concentrations below 1 ng/l in surface water and waste water . The recovery was 88-98% with a limit of detection of 0.1-2.4 ng/l depending on the compound and the matrix measured . This method was used to determine the occurrence of 17 beta-estradiol, 17 alpha-estradiol, estrone and 17 alpha-ethinylestradiol in the aquatic environment in The Netherlands . The data show that estrogenic hormones can be detected at low concentrations (up to 6 ng/l) at some locations in surface water . In selected effluents of waste water treatment plants estrone and 17 beta-estradiol were detected in concentrations in the ng/l range . Concentrations of 17 alpha-estradiol and the contraceptive 17 alpha-ethinylestradiol were in most of these samples below the limit of detection . Hormone glucuronides were not detected in most surface water and effluents.

Am Ind Hyg Assoc J, 1999 Jan-Feb, 60(1), 73 - 83
Occupational exposure to chemical and biological agents in the nonproduction departments of pulp, paper, and paper product mills: an international study; Teschke K et al.; As part of an international epidemiological study of workers in the pulp and paper industry, previously unpublished exposure measurements were assembled in a database . This article describes 7293 measurements in nonproduction departments from 147 mills in 11 countries . The greatest variety of agents was measured in the maintenance, construction, and cleaning department, where high exposures to asbestos, chromium {VI} compounds, copper, mercury in urine, nitrogen dioxide, ozone, styrene, sulfur dioxide, trichloroethylene, and welding fumes were observed . Measurements in the storage, yard, loading, and shipping department indicated high exposures to asbestos, carbon monoxide, fungal spores, nitrogen oxides, sulfur dioxide, and total dust . The steam and power generation department had high exposures to methyl mercaptan, silica, and total dust . Measurements in process and effluent water treatment, laboratory and research, engineering, and office, administration, and cafeteria areas had few elevated exposures . Throughout the nonproduction departments, measurements of pulp-production chemicals such as chlorine and sulfur compounds tended to be low, with many below detection limits . There were some problems with the available data; in particular, detection limits were often not specified, and the data tended to be clustered in such a way that sources of exposure variability could not be distinguished . Despite these problems, the data provide new insight into the exposures of nonproduction pulp and paper industry personnel.

Photodermatol Photoimmunol Photomed, 1999 Feb, 15(1), 22 - 7
PUVA-induced lymphocyte apoptosis: mechanism of action in psoriasis; Coven TR et al.; Psoralen plus ultraviolet A (PUVA), utilizing oral 8-methoxypsoralen (8-MOP), is a widely utilized and effective treatment for psoriasis vulgaris . Previous studies have suggested that PUVA's mechanism of action in psoriasis is a result of its direct lymphotoxic effects . Trimethylpsoralen (TMP), a potentially safer compound, has been found to be effective in psoriasis during bath water delivery . In this study we examined the relative antilymphocytic effects of TMP and 8-MOP through both flow cytometry and tissue analysis on lesional skin during clinical treatment . Based on FACS analysis on phytohemagglutinin-activated lymphocytes, we found TMP to be nearly 10,000 fold more lymphotoxic compared to 8-MOP . In addition, lymphocytes treated with 8-MOP or TMP with UVA displayed DNA degradation patterns typical of apoptotic cell death . These findings were consistent with our investigation of treated psoriatic skin, with virtual elimination of epidermal CD3+ T-cells following bath water treatment with TMP or 8-MOP . These results support the theory that the therapeutic effects of PUVA stem from its toxic effects on activated lymphocytes . If further investigation supports TMP's lack of carcinogenicity, this potent lymphotoxic treatment may prove to be one of the safest and most effective treatments for psoriasis.

Rev Environ Health, 1998 Oct-Dec, 13(4), 205 - 12
A multi-purpose system for water purification and sea-water softening; Barsky L et al.; A novel technique that can be used for reacting toxic carbon dioxide (CO2) emissions from power plants and other combustion wastes with sea water is described . A chemical interaction between CO2 and the cations in sea water, with the pH electrolytically regulated, can precipitate almost all the calcium and magnesium ions, as well as some sodium and potassium ions, as carbonates and bicarbonates . The carbonates and bicarbonates thus prepared can then be mixed with ash to yield a building material . Sulfur ions will be neutralized with calcium and magnesium, and the remaining ions can be removed using reverse osmosis or some other method . The technology and equipment for purification are based on modules that can be used for industrial waste-water, sea water, solutions, and otherwise . The module for separation of sand and suspended coarse substances consists of a tank for flocculation, coagulation, and precipitation of solid particles; and a low-pressure hydrocyclone . The module for purification from oil and fine suspensions is based on column flotation, flotation with a special ejector, and adhesion flotation . The module for ions and colloids consists of an absorbing filter with zeolite, fly ash, and other absorbing materials . Using a laboratory model consisting of a special mini-plant, we processed 10 L of factory-waste water containing more than 20 g/L organic content (compare with the upper limit of 0.02 g/L allowed by the Ministry of Environmental Protection in Israel) . After the experimental solution was treated and evaporated to a small bulk, the water obtained was almost clear . On the basis of the results in the model, we present a scaled-up process for the design, development, and production of equipment for and the assembly of a large installation for drainage and water purification.

Lancet, 1999 Jan 23, 353(9149), 272 - 7
Effect of monochloramine disinfection of municipal drinking water on risk of nosocomial Legionnaires' disease; Kool JL et al.; BACKGROUND: Many Legionella infections are acquired through inhalation or aspiration of drinking water . Although about 25% of municipalities in the USA use monochloramine for disinfection of drinking water, the effect of monochloramine on the occurrence of Legionnaires' disease has never been studied . METHODS: We used a case-control study to compare disinfection methods for drinking water supplied to 32 hospitals that had had outbreaks of Legionnaires' disease with the disinfection method for water supplied to 48 control-hospitals, with control for selected hospital characteristics and water treatment factors . FINDINGS: Hospitals supplied with drinking water containing free chlorine as a residual disinfectant were more likely to have a reported outbreak of Legionnaires' disease than those that used water with monochloramine as a residual disinfectant (odds ratio 10.2 {95% CI 1.4-460}) . This result suggests that 90% of outbreaks associated with drinking water might not have occurred if monochloramine had been used instead of free chlorine for residual disinfection (attributable proportion 0.90 {0.29-1.00}) . INTERPRETATION: The protective effect of monochloramine against legionella should be confirmed by other studies . Chloramination of drinking water may be a cost-effective method for control of Legionnaires' disease at the municipal level or in individual hospitals, and widespread implementation could prevent thousands of cases.

Ann N Y Acad Sci, 1998 Dec 13, 864, 142 - 52
Directed evolution of new enzymes and pathways for environmental biocatalysis; Wackett LP; Biocatalysis is important in both natural and engineered environments . The major global reactions in the biospheric cycling of carbon, nitrogen, and other elements are catalyzed by microorganisms . The global carbon cycle includes millions of organic compounds that are made by plants, microorganisms, and organic chemists . Most of those compounds are transformed by microbial enzymes . Degradative metabolism is known as catabolism and yields principally carbon dioxide, methane, or biomass . Microbial catabolic enzymes are a great resource for biotechnology . They are the building blocks for engineering novel metabolic pathways and evolving improved enzymes in the laboratory . Two multicomponent bacterial oxygeneases, cytochrome P450cam and toluene dioxygenase, catalyze the dechlorination of polyhalogenated C2 compounds . Seven genes encoding those functional enzyme complexes were coexpressed in a Pseudomonas and shown to metabolize pentachloreothane to nonhalogenated organic acids that were metabolized further to carbon dioxide . In another example, the enzyme catalyzing the dechlorination of the herbicide atrazine was subjected to iterative DNA shuffling to produce mutations . By using a plate screening assay, mutated atrazine chlorohydrolase that catalyzed a more rapid dechlorination of atrazine was obtained . The mutant genes were sequences and found to encode up to 11 amino acid changes . Atrazine chlorohydrolase is currently being used in a model municipal water treatment system to test the feasibility of using enzymes for atrazine decontamination . These data suggest that the natural diversity of bacterial catabolic enzymes provides the starting point for improved biocatalytic systems that meet the needs of commercial applications.

Environ Health Perspect, 1999 Feb, 107(2), 103 - 10
Exposure estimates to disinfection by-products of chlorinated drinking water; Weisel CP et al.; Exposure to disinfection by-products (DBPs) of drinking water is multiroute and occurs in households serviced by municipal water treatment facilities that disinfect the water as a necessary step to halt the spread of waterborne infectious diseases . Biomarkers of the two most abundant groups of DBPs of chlorination, exhaled breath levels of trihalomethanes (THMs) and urinary levels of two haloacetic acids, were compared to exposure estimates calculated from in-home tap water concentrations and responses to a questionnaire related to water usage . Background THM breath concentrations were uniformly low . Strong relationships were identified between the THM breath concentrations collected after a shower and both the THM water concentration and the THM exposure from a shower, after adjusting for the postshower delay time in collecting the breath sample . Urinary haloacetic acid excretion rates were not correlated to water concentrations . Urinary trichloroacetic acid excretion rates were correlated with ingestion exposure, and that correlation was stronger in a subset of individuals who consumed beverages primarily within their home where the concentration measurements were made . No correlation was observed between an average 48-hr exposure estimate and the urinary dichloroacetic acid excretion rate, presumably because of its short biological half-life . Valid biomarkers were identified for DBP exposures, but the time between the exposure and sample collection should be considered to account for different metabolic rates among the DBPs . Further, using water concentration as an exposure estimate can introduce misclassification of exposure for DBPs whose primary route is ingestion due to the great variability in the amount of water ingested across a population.

Cent Eur J Public Health, 1998 Nov, 6(4), 314 - 6
Hygiene aspects of drinking water ultrafiltration; Sefcova H; Ultrafiltration is highly effective method for removal of bacteria and viruses and does not produce organohalides associated with water treatment by chlorine gas . The aim was to assess the hygiene suitability of the unit for possible use in bottled water production . The ultrafiltration unit was in operation for 220 hours with simulated of varying duration . The running time (220 hours) and shut-down duration (to 5 hours) did not in any way influence the effectiveness of the module (100% filtration of aerobic colony count at 37 degrees C and 22 degrees C).

Am J Trop Med Hyg, 1998 Dec, 59(6), 941 - 6
Water distribution system and diarrheal disease transmission: a case study in Uzbekistan; Semenza JC et al.; Deteriorating water treatment facilities and distribution systems pose a significant public health threat, particularly in republics of the former Soviet Union . Interventions to decrease the disease burden associated with these water systems range from upgrading distribution networks to installing reverse osmosis technology . To provide insight into this decision process, we conducted a randomized intervention study to provide epidemiologic data for water policy decisions in Nukus, Uzbekistan, where drinking water quality is suboptimal . We interviewed residents of 240 households, 120 with and 120 without access to municipal piped water . Residents of 62 households without piped water were trained to chlorinate their drinking water at home in a narrow-necked water container with a spout . All study subjects (1583 individuals) were monitored biweekly for self-reported diarrheal illness over a period of 9.5 weeks . The home chlorination intervention group had the lowest diarrheal rate (28.8/1,000 subjects/month) despite lack of access to piped water in their homes . Compared with the two groups that did not receive the intervention this rate was one-sixth that of the group with no piped water (179.2/1,000 subjects/month) and one-third that of the households with piped water (75.5/1,000 subjects/month) . More than 30% of the households with piped water lacked detectable levels of chlorine residues in their drinking water, despite two-stage chlorination of the source water, and were at increased risk of diarrhea . Forty-two percent of these municipal users reported that water pressure had been intermittent within the previous two days . The dramatic reduction in diarrheal rates in the home-chlorination intervention group indicates that a large proportion of diarrheal diseases in Nukus are water-borne . The home-chlorination group had less diarrhea than the group with piped water, implicating the distribution system as a source of disease transmission . Taken together, these epidemiologic data would support the hypothesis that diarrhea in the piped water group could be attributed to cross-contamination between the municipal water supply and sewer, due to leaky pipes and lack of water pressure . Relatively inexpensive steps, including chlorination, maintaining water pressure, and properly maintaining the distribution system, rather than reverse osmosis technology, should reduce diarrheal rates.

Toxicology, 1998 Sep 15, 130(2-3), 141 - 54
Effects of dichloroacetate on glycogen metabolism in B6C3F1 mice; Kato-Weinstein J et al.; Dichloroacetate (DCA) is a by-product of drinking water chlorination . Administration of DCA in drinking water results in accumulation of glycogen in the liver of B6C3F1 mice . To investigate the processes affecting liver glycogen accumulation, male B6C3F1 mice were administered DCA in drinking water at levels varying from 0.1 to 3 g/l for up to 8 weeks . Liver glycogen synthase (GS) and glycogen phosphorylase (GP) activities, liver glycogen content, serum glucose and insulin levels were analyzed . To determine whether effects were primary or attributable to increased glycogen synthesis, some mice were fasted and administered a glucose challenge (20 min before sacrifice) . DCA treatments in drinking water caused glycogen accumulation in a dose-dependent manner . The DCA treatment in drinking water suppressed the activity ratio of GS measured in mice sacrificed at 9:00 AM, but not at 3:00 AM . However, net glycogen synthesis after glucose challenge was increased with DCA treatments for 1-2 weeks duration, but the effect was no longer observed at 8 weeks . Degradation of glycogen by fasting decreased progressively as the treatment period was increased, and no longer occurred at 8 weeks . A shift of the liver glycogen-iodine spectrum from DCA-treated mice was observed relative to that of control mice, suggesting a change in the physical form of glycogen . These data suggest that DCA-induced glycogen accumulation at high doses is related to decreases in the degradation rate . When DCA was administered by single intraperitoneal (i.p.) injection to naive mice at doses of 2-200 mg/kg at the time of glucose challenge, a biphasic response was observed . Doses of 10-25 mg/kg increased both plasma glucose and insulin concentrations . In contrast, very high i.p . doses of DCA (> 75 mg/kg) produced progressive decreases in serum glucose and glycogen deposition in the liver . Since the blood levels of DCA produced by these higher i.p . doses were significantly higher than observed with drinking water treatment, we conclude that apparent differences with data of previous investigations is related to substantial differences in systemic dose and/or dose-time relations.

Curr Opin Nephrol Hypertens, 1998 Nov, 7(6), 643 - 7
Hemofiltration and double high flux dialysis: risks and benefits; Bosch JP et al.; Convective therapies such as hemofiltration, hemodiafiltration and double high flux dialysis have been shown to improve treatment delivered and treatment tolerance when compared to conventional dialysis therapies . The risk associated with these treatments is primarily in the quality of the substitution fluid . Technological advances now permit on-line produced substitution fluid, thereby significantly reducing the cost associated with hemofiltration and hemodiafiltration . The quality of the substitution fluid is only assured when the quality of the RO water used is within the guidelines set by the Association for the Advancement of Medical Instrumentation (AAMI) . Therefore, the success of the application of this therapy is dependent on the water treatment protocols in the dialysis units . The success of this modality as a treatment for chronic renal failure is dependent on identifying those patient groups who will benefit most from this more efficient but more expensive treatment.

MMWR CDC Surveill Summ, 1998 Dec 11, 47(5), 1 - 34
Surveillance for waterborne-disease outbreaks--United States, 1995-1996; Levy DA et al.; PROBLEM/CONDITION: Since 1971, CDC and the U.S . Environmental Protection Agency have maintained a collaborative surveillance system for collecting and periodically reporting data that relate to occurrences and causes of waterborne-disease outbreaks (WBDOs) . REPORTING PERIOD COVERED: This summary includes data for January 1995 through December 1996 and previously unreported outbreaks in 1994 . DESCRIPTION OF THE SYSTEM: The surveillance system includes data about outbreaks associated with drinking water and recreational water . State, territorial, and local public health departments are primarily responsible for detecting and investigating WBDOs and for voluntarily reporting them to CDC on a standard form . RESULTS: For the period 1995-1996, 13 states reported a total of 22 outbreaks associated with drinking water . These outbreaks caused an estimated total of 2,567 persons to become ill . No deaths were reported . The microbe or chemical that caused the outbreak was identified for 14 (63.6%) of the 22 outbreaks . Giardia lamblia and Shigella sonnei each caused two (9.1%) of the 22 outbreaks; Escherichia coli O157:H7, Plesiomonas shigelloides, and a small round structured virus were implicated for one outbreak (4.5%) each . One of the two outbreaks of giardiasis involved the largest number of cases, with an estimated 1,449 ill persons . Seven outbreaks (31.8% of 22) of chemical poisoning, which involved a total of 90 persons, were reported . Copper and nitrite were associated with two outbreaks (9.1% of 22) each and sodium hydroxide, chlorine, and concentrated liquid soap with one outbreak (4.5%) each . Eleven (50.0%) of the 22 outbreaks were linked to well water, eight in noncommunity and three in community systems . Only three of the 10 outbreaks associated with community water systems were caused by problems at water treatment plants; the other seven resulted from problems in the water distribution systems and plumbing of individual facilities (e.g., a restaurant) . Six of the seven outbreaks were associated with chemical contamination of the drinking water; the seventh outbreak was attributed to a small round structured virus . Four of the seven outbreaks occurred because of backflow or backsiphonage through a cross-connection, and two occurred because of high levels of copper that leached into water after the installation of new plumbing . For three of the four outbreaks caused by contamination from a cross-connection, an improperly installed vacuum breaker or a faulty backflow prevention device was identified; no protection against backsiphonage was found for the fourth outbreak . Thirty-seven outbreaks from 17 states were attributed to recreational water exposure and affected an estimated 9,129 persons, including 8,449 persons in two large outbreaks of cryptosporidiosis . Twenty-two (59.5%) of these 37 were outbreaks of gastroenteritis; nine (24.3%) were outbreaks of dermatitis; and six (16.2%) were single cases of primary amebic meningoencephalitis caused by Naegleria fowleri, all of which were fatal . The etiologic agent was identified for 33 (89.2%) of the 37 outbreaks . Six (27.3%) of the 22 outbreaks of gastroenteritis were caused by Cryptosporidium parvum and six (27.3%) by E . coli O157:H7 . All of the latter were associated with unchlorinated water (i.e., in lakes) or inadequately chlorinated water (i.e., in a pool) . Thirteen (59.1%) of these 22 outbreaks were associated with lake water, eight (36.4%) with swimming or wading pools, and one(4.5%) with a hot spring . Of the nine outbreaks of dermatitis, seven (77.8%) were outbreaks of Pseudomonas dermatitis associated with hot tubs, and two (22.2%) were lake-associated outbreaks of swimmer's itch caused by Schistosoma species . INTERPRETATION: WBDOs caused by E . coli O157:H7 were reported more frequently than in previous years and were associated primarily with recreational lake water . This finding suggests the need for better monitoring of water quality and identification of sources of

Aviakosm Ekolog Med, 1998, 32(4), 28 - 33
{Immobilized catalase in water purification systems}; Nazarov NM et al.; The results of studies on producing the biocatalyst based on catalase immobilized in the fibers from triacetate are presented . The catalase producer is Penicillium fungus . Catalase was produced by precipitation with the use of ethyl alcohol from the cultural fluid with separate and unseparate mycelium . The highest activity of catalase in the cultural fluid is seen on the nutrient medium containing 4% of carbon source . For immobilization the water solution of enzyme was concentrated in the vacuum-rotor evaporator at temperature of 25 degrees C . The enzyme was included in the structure of fibers during the process of their formation . Of the fiber-producing polymers (cellulose triacetate, chlorine, polysulphone) the most enzymatic activity has the catalase-containing fibers derived from the cellulose triacetate, in this case, the fine fibers of biocatalyst have the higher specific activity . It is established that the fibers obtained by using catalase of microbiological origin possess high stability and their activity does not practically change in the aqueous environment . The unpurified catalase is one and a half higher than at purified catalase . Under laboratory conditions there turned out the experimental batches of fibers and there conducted their endurance tests . Catalase included in cellulase triacetate has effectively functioned during a period of 2 years purifying the distilled water containing 50 mg/l of hydrogen peroxide.

Commun Dis Public Health, 1998 Dec, 1(4), 234 - 8
Investigation of an outbreak of cryptosporidiosis associated with treated surface water finds limits to the value of case control studies; Hunter PR et al.; Fifty-two cases of cryptosporidiosis satisfied the case definition employed in investigation of an outbreak in Spring 1996 among residents of the Wirral peninsula supplied by a single water treatment plant using river water . The attack rate among those whose water was supplied solely from the plant was 1.42 per 10,000, compared with 0.42/10,000 among those having some but less than 50% supplied from it . Single oocysts were detected in treated water from this plant on four occasions during the investigation . A case control study did not demonstrate a significant association between illness and water consumption and no obvious failure in water treatment procedures occurred during the relevant period . Nevertheless, according to PHLS criteria, this outbreak was strongly associated with water, as the descriptive epidemiology was consistent and oocysts were detected, albeit in small numbers, in treated water . This paper discusses the value of detection of oocysts and case control studies in investigating waterborne outbreaks of cryptosporidiosis . Populations that normally drink surface water, particularly river water, are thought to be exposed repeatedly to cryptosporidium oocysts and so develop some protective immunity . Case control studies are therefore likely to have less power in the investigation of outbreaks in localities where the population normally drink treated surface water . Although oocysts are often isolated from treated surface waters without being associated with obvious disease in the population, their detection should still be considered in assessing the strength of association of waterborne outbreaks.

J Travel Med, 1997 Jun 1, 4(2), 58 - 60
Re-emergence of Cholera Vaccine; Berger SA et al.; Although epidemic cholera was first described in 1817, the disease probably has been common in the Indian subcontinent since ancient times.1 Until recently, a single bacterial type (Vibrio cholerae 01) has been responsible for each of the seven recorded cholera pandemics . The current epidemic began in Celebes (Sulawesi), Indonesia, in 1961, and is currently raging through all continents.2 During the 1990s, over 1 million cholera cases have been reported from Latin America, 2000 from Ukraine and the Russian Republic during 1994 alone (GIDEON computer software, C.Y . Informatics, Ramat Hasharon, Israel) . Of the 208,755 cases of cholera (5034 fatal) officially reported to the World Health Organization in 1995,3 41.1% were from Latin America, 34.0% from Africa, 24.4% from Asia, and 0.5% from Europe and Oceania . Interest in our own country of Israel stems from the popularity of tourism (over 1 million travelers exit Israel yearly) and the presence of disease in neighboring areas . Following an epidemic of 397 cases in Jerusalem during 1970, periodic outbreaks have occurred in Gaza, Judea and Samaria.4 Three tourists returned with the infection to Israel during the 1980s, all from Egypt (which officially claims to have no cholera).5 Despite universal interest in this ancient disease, medical science has long been frustrated in its search for an effective vaccine . The most important 'vaccine' against cholera is common sense, and consists of intelligent eating and drinking while in endemic areas . For example, local raw fish (ceviche) is a common source of the disease in Latin America, while shellfish (particularly oysters) are often implicated along the American Gulf Coast . Virtually all forms of water purification are effective against Vibrio cholerae . Although antibiotic prophylaxis might be considered in some circumstances (doxycycline; or a quinolone in areas of tetracycline resistance), it is not routinely advocated.

Lett Appl Microbiol, 1998 Oct, 27(4), 189 - 92
Antimicrobial effect of tetramethyldithiooxamide and its application as a biocide; Tabakova SV et al.; Tetramethyldithiooxamide (TMDTOA) is a stable and effective inhibitor of metal corrosion . The antimicrobial effects of TMDTOA and its metal compounds were investigated with regard to their use as biocides for water treatment . Growth of a variety of strains of bacteria and yeasts was completely inhibited at 400 mumol l-1 TMDTOA or its metal complexes . At 100 mg l-1 there was a 99.99% reduction in the number of viable micro-organisms; this activity persisted for 1-3 months . TMDTOA can be produced cheaply at 98% purity by a novel method, representing an alternative cost-effective water treatment agent combining corrosion-inhibiting and biocide characteristics.

Lancet, 1998 Jul 4, 352(9121), 21 - 6
Fatal microcystin intoxication in haemodialysis unit in Caruaru, Brazil; Pouria S et al.; BACKGROUND: After a drought in February, 1996, all 126 patients in a haemodialysis unit in Caruaru, north-east Brazil, developed signs and symptoms of acute neurotoxicity and subacute hepatotoxicity following the use of water from a lake with massive growth of cyanobacteria (blue-green algae) . 60 patients died . METHODS: Besides recording clinical details and outcome at follow-up, we arranged laboratory, radiological, and histological investigations on the patients and toxicological studies of serum and haemodialysis water filters . FINDINGS: The acute presentation was with malaise, myalgia and weakness, nausea and vomiting, and tender hepatomegaly, with a range of neurological symptoms from tinnitus, vertigo, headaches, and deafness to blindness and convulsions . Liver injury ranged from abnormal liver-function test results to rapidly progressive and fatal hepatic failure . Biochemical investigations revealed gross hyperbilirubinaemia, abnormal liver enzyme activities, and hypertriglyceridaemia, but there was no evidence of haemolysis or microangiopathy . Histology revealed a novel acute toxic hepatitis with diffuse panlobular hepatocyte necrosis, neutrophil infiltration, canalicular cholestasis, and regenerative multinucleate hepatocytes . Samples of serum, dialysis filters, and water-treatment columns contained microcystins, the highly toxic low-molecular-weight hepatotoxins produced by cyanobacteria . INTERPRETATION: Cyanobacteria present water-borne hazards to health via drinking water and recreational water . Haemodialysis presents an additional high-risk exposure route: when they enter directly into the circulation, microcystins can lead to fatal clinical syndromes ranging from acute neurotoxic illness to subacute liver failure.

Appl Environ Microbiol, 1998 Nov, 64(11), 4460 - 6
Sedimentation of free and attached Cryptosporidium oocysts and Giardia cysts in water; Medema GJ et al.; Experimental analysis of the sedimentation velocity of Cryptosporidium parvum oocysts and Giardia lamblia cysts was compared with mathematical description of their sedimentation velocities by using measurements of (oo)cyst size and density and the density and viscosity of the sedimentation medium to determine if the sedimentation kinetics of freely suspended oocysts of C . parvum and cysts of G . lamblia can be described by Stokes' law . The theoretically calculated sedimentation kinetics showed a good agreement with the experimentally observed kinetics . Both showed a decline in sedimentation velocity over time, caused primarily by variation in (oo)cyst density . The initial apparent sedimentation velocities in Hanks balanced salt solution at 23 degrees C was 0.35 micron . s-1 for oocysts and 1.4 micron . s-1 for cysts . (Oo)cysts that enter the surface water environment by discharges of biologically treated sewage may be attached to sewage particles, and this will affect their sedimentation kinetics . Therefore, (oo)cysts were mixed with settled secondary effluent . (Oo)cysts readily attached to the (biological) particles in effluent; 30% of both cysts and oocysts attached during the first minutes of mixing, and this fraction increased to approximately 75% after 24 h . The sedimentation velocity of (oo)cysts attached to secondary effluent particles increased with particle size and was (already in the smallest size fraction {1 to 40 micron}) determined by the sedimentation kinetics of the effluent particles . The observed sedimentation velocities of freely suspended (oo)cysts are probably too low to cause significant sedimentation in surface water or reservoirs . However, since a significant proportion of both cysts and oocysts attached readily to organic biological particles in secondary effluent, sedimentation of attached (oo)cysts after discharge into surface water will probably be a significant factor in the environmental ecology of C . parvum and G . lamblia . Attachment to particles influences not only sedimentation of (oo)cysts in surface water but also their behavior in drinking water treatment processes.

Clin Ter, 1998 Mar-Apr, 149(2), 127 - 30
{Clinical-epidemiological study of the efficacy of thermal therapy in gastroenterologic diseases}; Scalabrino A et al.; PURPOSE: To evaluate the therapeutic effects of drinking mineral water, its influence on gastrointestinal drug consumption as well as on working days missed in patients with dyspeptic syndrome or chronic constipation due to irritable bowel syndrome . MATERIALS AND METHODS: A questionnaire was sent to 1500 physicians and 965 forms were available concerning patients who had mineral water treatment at Montecatini . RESULTS: Mineral water therapy determined a striking short- and medium-term improvement on clinical symptoms . Furthermore, this treatment reduced gastrointestinal drug consumption per year, as well as the number of working days missed . CONCLUSIONS: This epidemiological study confirms the utility of drinking mineral water in the treatment of some gastrointestinal syndromes either in the short and in the medium run.

Poult Sci, 1998 Oct, 77(10), 1488 - 91
Sodium chloride concentration in drinking water and eggshell quality; Damron BL; Two experiments with White Leghorn hens (36 and 49 wk old, respectively) were conducted to examine the effects of varying NaCl concentrations provided through drinking water upon eggshell quality . Experiments were of 6 and 5 wk duration, respectively . Seven replicate pens of five individually caged hens received each water treatment . Treatments were the same in both studies and consisted of low-Na (9 ppm) tap water supplemented with 0, 200, 400, 600, or 800 ppm NaCl . Solutions were prepared weekly . All eggs produced were examined visually for shell defects, and egg weight and specific gravity were determined . In the second experiment, eggs from 2 consecutive d were also broken out each week for Haugh Unit determinations . In both studies, hen-day egg production, daily feed and water intake, egg weight, and body weight change over the experimental period were not influenced by any level of waterborne NaCl . Haugh Units were also not affected in Experiment 2 . In contrast to other literature reports, visually determined shell defects and egg specific gravity were not adversely affected by NaCl supplementation of layer drinking water.

Epidemiol Infect, 1998 Aug, 121(1), 109 - 19
Outbreaks of waterborne infectious intestinal disease in England and Wales, 1992-5; Furtado C et al.; Following the introduction of an improved surveillance system for infectious intestinal disease outbreaks in England and Wales, the Public Health Laboratory Service Communicable Disease Surveillance Centre received reports of 26 outbreaks between 1 January 1992 and 31 December 1995 in which there was evidence for waterborne transmission of infection . In these 26 outbreaks, 1756 laboratory confirmed cases were identified of whom 69 (4%) were admitted to hospital . In 19 outbreaks, illness was associated with the consumption of drinking water from public supplies (10 outbreaks) or private supplies (9 outbreaks) . The largest outbreak consisted of 575 cases . In 4 of the remaining 7 outbreaks, illness was associated with exposure to swimming pool water . Cryptosporidium was identified as the probable causative organism in all 14 outbreaks associated with public water supplies and swimming pools . Campylobacter was responsible for most outbreaks associated with private water supplies . This review confirms a continuing risk of cryptosporidiosis from chlorinated water supplies in England and Wales, and reinforces governmental advice to water utilities that water treatment processes should be rigorously applied to ensure effective particle removal . High standards of surveillance are important for prompt recognition of outbreaks and institution of control measures . As microbiological evidence of water contamination may be absent or insufficient to implicate a particular water supply, a high standard of epidemiological investigation is recommended in all outbreaks of suspected waterborne disease.

Poult Sci, 1998 Sep, 77(9), 1287 - 96
Comparative effects of added sodium chloride, ammonium chloride, or potassium bicarbonate in the drinking water of broilers, and feed restriction, on the development of the ascites syndrome; Shlosberg A et al.; A hypothesis that the ionic composition of drinking water might affect development of the ascites syndrome in broilers was investigated in two trials . The first trial comprised four groups of 650 male chicks . A control treatment was normal tap water and the other three treatments comprised the addition to the tap water of 1,000 mg/L sodium as NaCl, 5,000 mg/L NH4Cl, or 5,000 mg/L KHCO3, supplied from age 2 to 47 d . At Day 28, equally sized subsets of these groups were moved to individual cages, where they received a severe exposure to ambient cold . The development of the ascites syndrome was monitored by measurements of hematocrit and arterial blood oxygen saturation (PaO2) by oximetry, body weight, and examination of dead birds for cause of death . Mortality from ascites in cold-exposed birds from Days 28 to 47 was 28, 48, 40, and 16% in the tap water, NaCl, NH4Cl, and KHCO3 groups, respectively; only the NaCl mortality was significantly different from the tap water mortality . The KHCO3 treatment increased PaO2 (compared with tap water treatment) at Day 28 by 5.5% and at Day 35 by 10.5%, but not at Day 42 . The KHCO3 caused a reduction in body weight, which was 13% less than the tap water group at Day 42, probably due to a chronic toxicity . The second trial specifically examined the same parameters with lower water levels of KHCO3 (3,000 and 1,000 mg/L), in comparison to a 10% feed restriction protocol, in order to clarify whether the increased PaO2 was due to a specific effect of the KHCO3 or was a metabolic manifestation of a reduced growth rate . The 3,000 mg/L KHCO3 treatment had no effect on PaO2, but the 1,000 mg/L treatment augmented PaO2 by 5.3% at Day 35 (but not at Days 28 or 42), without reducing the final body weight . The feed restriction group showed an elevated PaO2 of 5.4% at Day 35 (but not at Days 28 or 42), with no reduction in the final body weight . The inclusion of 1,000 mg/L of KHCO3 into the drinking water of broilers or a temporary 10% feed restriction may be means to augment PaO2.

Chemosphere, 1998 Sep, 37(6), 1045 - 61
Behavior of organic polymers in drinking water purification; Lee JF et al.; Synthetic organic polymers used to purify drinking water are severely limited in that their impurities and by-products harm human health . In this study, the undesired effects resulted from chlorination and the enhanced attenuation of toxic organic compounds in drinking water from using synthetic organic polymer coagulants were investigated . In the simulated drinking water purification processes, synthetic organic polymers were used as coagulant aids, reacted with a disinfectant(chlorine) and formed a large number of volatile organic compounds (VOCs) . Chloroform and benzene which, are carcinogenic compounds, had the maximum formation potential . Experimental results indicated that the total formation potential of these disinfection by-products significantly increased in the presence of turbidity . On the other hand, adding organic polymers to the coagulation systems resulted in more extensive remove of toxic organic compounds and turbidity . In coagulation and flocculation processes, the formation of clay/polymer complexes can facilitate the removal of toxic organic compounds in contaminated water.

J Food Prot, 1998 Jan, 61(1), 19 - 25
Use of hot water for beef carcass decontamination; Castillo A et al.; Hot water treatment of beef carcass surfaces for reduction of Escherichia coli O157:H7, Salmonella typhimurium, and various indicator organisms was studied using a model carcass spray cabinet . Paired hot carcass surface regions with different external fat characteristics (inside round, outside round, brisket, flank, and clod) were removed from carcasses immediately after the slaughter and dressing process . All cuts were inoculated with bovine feces containing 10(6)/g each of rifampicin-resistant E . coli O157:H7 and S . typhimurium, or with uninoculated bovine feces . Surfaces then were exposed to a carcass water wash or a water wash followed by hot water spray (95 degrees C) . Counts of rifampicin-resistant Salmonella and E . coli or aerobic plate count (APC) and coliform counts were conducted before and after each treatment . All treatments significantly reduced levels of pathogens from the initial inoculation level of 5.0 log(10) CFU/cm2 . Treatments including hot water sprays provided mean reductions of initial counts for E . coli O157:H7 and S . typhimurium of 3.7 and 3.8 log, APC reductions of 2.9 log, and coliform and thermotolerant coliform count reductions of 3.3 log . The efficacy of hot water treatments was affected by the carcass surface region, but not by delaying the treatment (30 min) after contaminating the surface . Verification of efficacy of hot water interventions used as critical control points in a hazard analysis critical control point (HACCP) system may be possible using coliform counts.

Chemosphere, 1998 Aug, 37(4), 593 - 606
Development of surrogate organic contaminant parameters for source water quality standards in Taiwan, ROC; Chang EE et al.; The objective of this research was to develop a rationale for selecting representative water quality parameters for organic contaminants and microorganisms and determining their respective contaminant level (or regulated value) for the source water quality standards in Taiwan . It was observed that chemical oxygen demand (COD) and total organic carbon (TOC) have strong correlation with UV254 in spite of the raw water which suggests, TOC and COD should be regarded as the surrogate parameters for water quality concerns . It was also proposed to implement 4.0 mg/L of TOC as a source water criteria at the present time and to adopt a more stringent value (2.0 mg/L of TOC) in the next phase (at 2002) . The total coliform regulated from 10,000 to 20,000 most probable number (MPN)/100 ml level appears to be the most economic and logical way to control trihalomethanes (THM) formation and disinfection efficiency at the water treatment plant in Taiwan.

Vet J, 1998 Jul, 156(1), 59 - 65
Pharmacokinetics and efficacy of amoxycillin in the treatment of an experimental Streptococcus bovis infection in racing pigeons (Columba livia); Soenens J et al.; The pharmacokinetics of amoxycillin in pigeons (Columba livia) and the efficacy of amoxycillin treatment in pigeon streptococcosis, were investigated . After intravenous administration of 150 mg.kg-1 amoxycillin, the drug plasma concentration-time profile fitted an open two-compartment model . Amoxycillin was quickly cleared from the circulation with a mean half-life of 66 min and showed a distribution volume of 0.9 L.kg-1 . The absolute oral bioavailability of amoxycillin was 50.1% . A 5-day drinking water treatment with amoxycillin (1500 mg.L-1, corresponding to 112.0 mg.kg-1.day-1 during day-light hours) significantly reduced the postinoculation morbidity in pigeons experimentally infected with Streptococcus bovis, compared to untreated infected controls.

Vet J, 1998 Jul, 156(1), 41 - 9
Rehydration following exercise: effects of administration of water versus an isotonic oral rehydration solution (ORS); Marlin DJ et al.; The effects of administering (1) 6L isotonic oral rehydration solution (ORS), similar in composition to plasma (except for an elevated potassium concentration) and with an osmotic skeleton and (2) 6L water (no osmotic skeleton), were evaluated in five thoroughbred horses following exercise-induced dehydration . The horses were exercised on a treadmill for 10 min at walk (1.7 m.s-1; approximately 15% VO2max), 40 min at trot (3.7 m.s-1; approximately 25% VO2max) and 10 min at walk (1.7 m.s-1; approximately 15% VO2max) . Exercise was undertaken on a 3 degrees incline at 30 degrees C/80% RH . Solutions of water or ORS at 20 degrees C were administered by nasogastric tube over 60s 5 min following exercise . Mean weight loss following exercise was 9.2 +/- 1.7 kg (2.0 +/- 0.4% body weight; mean +/- SEM) with water and 9.2 +/- 1.1 kg (2.0 +/- 0.2% body weight) with ORS and was not different between treatments (P > 0.05) . Water treatment resulted in a fall in plasma {Na+} (approximately 3 mmol.L-1) and C1- (1-2 mmol.L-1) concentrations by 30 min after administration and the effect persisted until the end of the study (300 min post fluids) . There was little change in plasma total protein (TP) from that at the end of exercise, suggesting a failure of water to restore or maintain PV . In contrast, ORS administration resulted in a small increase in plasma {Na+} (1-2 mmol.L-1) and {Cl-} (2-3 mmol.L-1) with a corresponding decrease in plasma TP . By 120 min post ORS, plasma TP and PV were no longer significantly different from rest or pre-exercise (P > 0.05), whilst with water, TP was elevated (approximately 3-4 g.L-1) and PV reduced (approximately 4-5 mL.kg-1) . Total urine output was not significantly different between water (1096 +/- 135 mL) and ORS (750 +/- 215 mL, P > 0.05) . Estimates of expected plasma volume and electrolyte concentration changes as a result of either treatment compared well with measured changes of TP and PV . On the basis of calculated or measured changes, it was estimated that only 1L of water contributed to rehydration following exercise compared to 4L isotonic, plasma-like ORS . The administration of 6L ORS restored the PV deficit induced by exercise with minimal or no disturbance of plasma electrolyte concentrations . In contrast, water alone resulted in minimal improvement in PV . When fluid intake after periods of fluid loss, such as induced by exercise or transport, is not accompanied by food intake, the present study has clearly demonstrated that water alone is ineffective in promoting rehydration compared with an isotonic, plasma-like ORS.

Zentralbl Hyg Umweltmed, 1998 Jun, 201(2), 189 - 98
Isolation of Arcobacter butzleri in raw water and drinking water treatment plants in Germany; Jacob J et al.; A total of 147 "Campylobacter-like" strains were isolated from six drinking water treatment plants within a two year investigation period . The strains were characterized by bio-, and serotyping according the scheme for Arcobacter butzleri . The result was that 100 strains were typed as Arcobacter butzleri, 17 strains as Arcobacter butzleri-like and 6 strains as Campylobacter jejuni/coli . 24 strains were typed as Arcobacter spp . The strains isolated from the treatment plants showed the same serotypes as described for human isolates . Therefore the spread of Arcobacter organisms via the drinking water path must be suspected.

Chemosphere, 1998 Aug, 37(3), 451 - 64
Application of a Finnish mutagenicity model to drinking waters in the U.S; Schenck KM et al.; Recent epidemiological studies conducted in Finland have reported a positive correlation between the mutagenicity of chlorinated drinking waters and certain human cancers . In these studies, past exposure to drinking water mutagenicity was assessed using a model developed by Vartiainen et al . {1} based on data collected in Finland . In this model, mutagenicity, as determined in the Ames assay, is a function of the total organic carbon (TOC) concentration of the water, chlorine dose, and to a minor extent, the concentration of ammonia . A study has been initiated to assess the applicability of this model to source waters and water treatment practices in the United States . Water samples were collected from three full-scale treatment plants and one pilot-scale plant . All the plants used chlorine exclusively for disinfection . One full-scale plant used ground water . Surface water sources were used by the other plants . TOC and ammonia concentrations were determined analytically and chlorine doses were obtained from the treatment plants . The water samples were concentrated by XAD resin adsorption for testing in the Ames assay . The observed levels of mutagenicity in the finished waters were 1.5 to 2-fold higher than those predicted using the model as specified in Vartiainen et al . {1} . Consequently, further validation is needed prior to widespread use of the Finnish model to assess exposure to mutagenicity in chlorinated drinking waters in the United States.

Neuroepidemiology, 1998, 17(3), 111 - 5
Epidemic neuropathy in Cuba: a public health problem related to the Cuban Democracy Act of the United States; Roman GC; In 1992, the USA embargo on Cuba was tightened through the passage of the Cuban Democracy Act (CDA) that explicitly restricts food and medical supplies . The embargo has contributed to cause a number of public health problems in Cuba including: (1) an epidemic of more than 50,000 cases of optic and peripheral neuropathies in 1992-1993, resulting from dietary deficiency; (2) an epidemic of esophageal stenoses in toddlers who inadvertently drank liquid lye as a result of a soap shortage for which liquid lye was substituted; (3) an outbreak of Guillain-Barre syndrome in Havana, in June and July 1994, resulting from water contamination due to lack of chemicals for water treatment to eliminate Campylobacter sp.; (4) outbreaks of self-inflicted disease and injuries caused by rioting among Cubans detained at the US Naval base at Guantanamo Bay, and (5) a decline in medical practice standards and public health indicators in Cuba resulting from the enactment of the CDA, documented by the American Public Health Association in 1993 and confirmed in March 1997 by the American Association for World Health . Despite this evidence, the Cuban embargo remains a politically sensitive subject in the USA, resistant to public health concerns, as evidenced by the recent passage of the Helms-Burton Act . The public health effects of the CDA need to be reviewed with possible revocation or at least modification.

Zentralbl Hyg Umweltmed, 1997 Aug, 200(2-3), 163 - 71
{Microbiologic/hygienic evaluation of the risk potential of bacteria from soil and water sources in combination with biotechnologic risks of soil restoration}; Dott W et al.; Biological cleanup-processes removing contaminations from soil and ground-water can be carried out "ex-situ" or "in situ" . The pollutants are mineralized (totally or partly) by microorganisms . The successful application of bioremediation techniques often leads to an increase of aerobic and facultatively anaerobic bacteria in soil and/or groundwater, a fact that triggered discussions about a potential biological risk originating from these microorganisms . In this study the identification results of 10,200 microorganisms isolated from 109 ground-water- and 152 soil-samples of different sites contaminated with mineral oil or chlorinated aromatics are evaluated with respect to a possible biological risks originating from these microorganisms . According to their biological risk potential, 19.2% (1958) of the isolated organisms can be grouped into risk-groups II, that means they they are able o cause human disease but it is unlikely that they are spread to the community and there is effective prophylaxis or treatment available . The majority of isolates (81.8%) are grouped into risk group I, meaning that it is very unlikely that they cause a human disease . All these microorganisms are either adsorbed to the soil-matrix or within a closed system of a water-treatment-plant, so that the risk of infection is very unlikely for healthy individuals (regarding possible pathways of infection) . The risk potential in waste-water-treatment-plants is regarded to be significantly higher than in biological soil-cleanup processes, because of the specific origin of the bacteria and the possible formation of aerosols.

J Appl Microbiol, 1998 Apr, 84(4), 467 - 77
Development of a risk assessment for BSE in the aquatic environment; Gale P et al.; Bovine spongiform encephalopathy (BSE) is believed to be transmitted by the ingestion of proteinaceous agents called prions which accumulate in the brain and spinal cord of infected bovines . Concern has been expressed about the risks of transmission of BSE to humans through BSE prions discharged to the aquatic environment from rendering plants, abattoirs and landfills . The disease-related form of the prion protein is relatively resistant to degradation, and infectivity decays rather slowly in the environment . Levels of disinfection used for drinking water treatment would have little effect . This paper presents the assumptions which were used to model the risks from a rendering plant disposing of cull cattle carcasses in the catchment of a chalk aquifer which is used for a drinking water abstraction . The risk assessment approach focused on identifying the hydrogeological and physical barriers which would contribute to preventing BSE infectivity gaining entry to the aquifer . These barriers included inactivation of BSE agent by the rendering process, removal from the effluent by treatment at the plant, filtration and adsorption in the clay and chalk, and dilution in the ground water . The importance in environmental risk assessment of the cow-to-man species barrier is considered . Two key conclusions about the environmental behaviour of the BSE agent are that prion proteins are 'sticky' and bind to particulates, and that the millions of BSE prion molecules comprising a human oral ID50 are subject to some degree of dispersion and hence dilution in the environment . Assuming the rendering plant processes 2000 cull cattle carcasses per week, the risks to drinking water consumers were estimated to be remote . Indeed, even using worst case assumptions an individual would have to consume 21 d-1 of tap water for 45 million years to have a 50% chance of infection through drinking water drawn from the aquifer.

Environ Res, 1998 May, 77(2), 98 - 103
Methylmercury dose estimation from umbilical cord concentrations in patients with Minamata disease; Akagi H et al.; The methylmercury exposure of patients with congenital or infantile Minamata disease is known only from a small number of analyses of umbilical cords . Four laboratories in Japan have analyzed a total of 176 samples of umbilical cord tissue obtained from Minamata . The highest concentrations were seen in cord tissue from children born during 1950-1965, i.e., the peak period of acetaldehyde production in Minamata before installation of waste water treatment . Twenty-four samples from patients diagnosed with Minamata disease showed a median mercury concentration of 1.63 microg/g and differed significantly from levels seen in cord tissue from control children . However, children diagnosed with mental retardation had mercury concentrations in cord that were intermediate between the two other groups . Using regression coefficients obtained at a study conducted at the Faroe Islands, the median cord mercury concentration from the children with Minamata disease is estimated to correspond to about 216 microg/L cord blood and 41 microg/g in maternal hair . Based on correlations reported in the literature, the median daily mercury intake of the women whose children developed Minamata disease can then be estimated at about 225 microg . Although these children had fully developed Minamata disease, the estimates of median mercury levels are only four to five times higher than current mercury exposure limits .

Nephrol Dial Transplant, 1998, 13 Suppl 5, 12 - 6
Water quality for on-line haemodiafiltration; Cappelli G et al.; The term 'ultrapure water' is a common way to define water used for on-line treatments: it refers to the absence of chemical, organic and microbiological contamination . To be more accurate in definition, every known and potential contaminant has to be fixed at its limit value . AAMI recommendations and various Pharmacopoeias have set limits for dialysate based on traditional dialysis treatments, but on-line treatments should also be regulated by guidelines for infusion solutions . Modern water treatment technology allows us to obtain a proper chemical quality both for dialysate and infusion solutions in on-line dialysis . Technology alone, however, cannot guarantee adequate microbiological quality if water treatment is not linked to the appropriate maintenance, monitoring, cleaning and sanitizing procedures . On-line dialysis treatments, as well as high-flux dialysis, use the monitor as an on-site pharmaceutical factory where sterilization by filtration forces nephrologists to look for procedures to keep sterile water sterile.

Biomed Sci Instrum, 1997, 34, 87 - 92
Design of a closed system water tunnel for lamprey swimming analysis; McIntosh CM et al.; This work presents a swim mill design that can be used to study locomotor behavior in intact awake lamprey . The design is constrained by the swimming characteristics and anatomy of young adult lamprey and allows for electrophysiological monitoring of muscle activity and imaging of motor behavior . The design has a test section for animal containment and monitoring of motor behavior, a water reservoir, a water pump, and equipment for biological adaptations (water purification, chilling, & aeration systems) . The 36 sq . inch acrylic test section is preceded by a turbulence-reducing converging nozzle, while a 1400 gallon reservoir maintains the system's hydrostatic head and acts as a settling chamber . This swim mill design will be used to examine lamprey swimming behavior under different environmental conditions (e.g., water velocity, turbulence, external perturbations).

Rev Clin Esp, 1997 Dec, 197(12), 819 - 21
{Traveller counseling by embassies and consulates}; Montanes Alcantara F et al.; BACKGROUND: Before travelling to developing countries is necessary to seek accurate health advice . This paper evaluate the quality of travel information given out in Spain by other embassies and consulates of different countries . METHODS: The information was regarded through a telephone survey calling to 32 embassies and consulates of countries in Asia, Africa and South and Central America posing as potential travellers seeking advice . RESULTS: Of the 15 countries where yellow fever is endemic only 53% advised the appropriate immunization . Malaria prophylaxis was recommended in over 41% of the countries in areas of risk for malaria, denning the existence of malaria the 25% . Other immunizations such as hepatitis, tetanus, typhus was recommended by the 12.5% and over 25% mentioned additional precautions (water purification, insect repellents, food ...) . 53% referred us to other sources of information in public health departments and travel clinics . CONCLUSIONS: Diplomatic representations are still not an ideal source of pretravel advice . An accurate advice should be sought from health units of international vaccines and Tropical Medicine.

Chemosphere, 1998 May, 36(12), 2593 - 606
Developments in solar photocatalysis for water purification; Vidal A; Photocatalytic processes in the presence of titanium dioxide provide an interesting route to destroy hazardous organic contaminants, being operational in the UV-A domain with a potential use of solar radiation . In this paper, some specific contaminant classes of interest such as ethylbenzene, gamma-lindane and EPTC have been tested at laboratory scale and in the field to determine the feasibility of the photocatalytic oxidation of organic contaminants in water . Our preliminary results at laboratory scale with these chemicals have provided a better understanding of the photocatalytic process which seems to be efficient and not selective . The application of these processes in removal of gamma-lindane from water operating in a parabolic trough concentrator has demonstrated to be effective, being possible to reduce 99.9% of gamma-lindane levels in water in acceptable times.

Chemosphere, 1997 Feb, 34(4), 807 - 15
Biodegradation and aquatic toxicity of beta-alaninediacetic acid (beta-ADA); Nitschke L et al.; The aquatic toxicity and biodegradability of the new chelating agent beta-alaninediacetic acid (beta-ADA) were investigated . There is no inhibition effect of beta-ADA in the daphnia magna 24 h test up to a concentration of 1000 mg/L . The algal growth inhibition test resulted in an EC 50 of 19.7 mg/L . An EC 20 of 740 mg/L was determined in the luminescent bacteria test . An EC 50 was not obtained in this test up to a concentration of 2000 mg/L beta-ADA . The degree of biodegradation of beta-ADA was determined in a static and a continuous test . The beta-ADA removal reached 98% at the end of the test after eight weeks in the continuous test which was carried out with laboratory activated sludge units simulating a waste water treatment plant . Further, biodegradation and toxicity tests were coupled, i.e . the effluents of the laboratory activated sludge units were applied in the toxicity tests . A higher toxicity of the effluents of the test units in comparison with the control unit was not observed.

Anal Chem, 1998 Apr 15, 70(8), 1639 - 45
Near-ultraviolet evanescent-wave absorption sensor based on a multimode optical fiber; Potyrailo RA et al.; Fiber-optic near-ultraviolet evanescent-wave sensors have been constructed, and their feasibility for practical applications has been demonstrated . The sensors, used for the detection of ozone near the 254-nm peak of the Hartley absorption band, were fabricated from coiled segments of low-cost multimode plastic-clad silica optical fibers . The sensing sections were produced alternatively by stripping only the protective jacket from the fiber to expose the gas-permeable silicone cladding or by stripping the jacket and the cladding to expose the bare-silica fiber core . Response characteristics are given, including sensitivity to ozone, reversibility, and aging effects . The useful lifetime was unacceptably short for the sensor that employed the bare-silica core, whereas the exposed-cladding sensor demonstrated good stability over the entire two-month period of investigation . The latter, more useful sensor demonstrated a linear response to ozone over the range 0.02-0.35 vol% and a reversible response with a time constant on the order of 1 min . Differences in ozone absorption spectra obtained in the transmission and evanescent-wave modes are discussed . Projected applications of the new exposed-cladding sensor include ozone determination in water-treatment processes and ozone production plants.

Lett Appl Microbiol, 1998 Feb, 26(2), 98 - 100
Degradation of geosmin-like compounds by selected species of gram-positive bacteria; Saadoun I et al.; Biodegradation of geosmin produced by Streptomyces halstedii (A-1 strain) was investigated using seven Gram-positive bacteria . Bacterial action on the A-1 extract was followed at 15, 45 and 120 min . Bacillus cereus ssp . thuringiensis HD-1, B . cereus 3711 and B . cereus ssp . mycoides 4379 showed no effect . However, Arthrobacter atrocyaneus, Arth . globiformis, Chlorophenolicus N-1053 and Rhodococcus maris caused a colour change from blue to yellow (positive reaction) . These data suggest that geosmin can be degraded by specific species of Gram-positive bacteria . Biodegradation of geosmin, which causes bad odour in drinking water, can be used as a new technology in water treatment.

Adv Parasitol, 1998, 40, 241 - 78
Water-borne cryptosporidiosis: detection methods and treatment options; Fricker CR et al.; Since the infamous outbreak in Milwaukee, WI, USA, of water-borne cryptosporidiosis affecting over 400,000 people, there have been at least 20 smaller outbreaks associated with this parasite in the UK and North America . These events have led to an explosion of interest in and research on the nature of cryptosporidiosis as a dangerous water-borne pathogen, particularly patients with acquired immune deficiency syndrome (AIDS) . In addition, several major environmental laws and proposed regulations specifically address the control of this parasite . The possible ramifications of these laws include billions of dollars of modifications to water-treatment facilities in the USA . Unfortunately, the methods used to gather the information on which these laws are based have serious deficiencies that could lead to gross underestimation of the magnitude of this problem . The present review considers gaps in our understanding of water-borne cryptosporidiosis, new methods under investigation that could improve our ability to monitor water for the presence of this organism, and treatment and control strategies to limit the threat to our water supplies.

Can J Microbiol, 1998 Feb, 44(2), 190 - 4
Potentiation of the virucidal activity of sterilized natural waters; Quignon F et al.; After heat, conductivity has been described as the second most inactivating factor of viruses in surface waters . Using poliovirus-1, we showed that a highly significant linear relationship between virus inactivation rate and water conductivity can be obtained for most of the tested sterilized water samples . Using sterile saline solutions, we demonstrated that this apparent relationship is false, i.e., virus inactivation rate is not affected by water conductivity alone . With the hypothesis that salts may serve to potentiate the antiviral activities of certain microbiological substances that are supposed to be found in the tested samples, we can explain the apparent relationship observed in this study and in similar ones . As a consequence, an effective water treatment could be responsible for the removal of both viruses and some virus-inactivating factors . Alternatively, virus-inactivating capability of a given water resource could be enhanced along with its hardness or its degree of mineralization.

Acta Biochim Pol, 1997, 44(3), 549 - 56
Energy minimization of globular proteins with solvent effects included . Comparison of empirical solvation energy terms and explicit water treatment; Kierzek A et al.; The effect of an empirical solvation energy term on energy minimization of ribonuclease T1 was established using different sets of Atomic Solvation Parameters . The results are compared to minimization in vacuo and in a 10 A water shell . The best solvent model as judged from the comparison to the crystal structure was an empirical solvation potential derived from free energies of transfer of amino-acid side-chain analogues from vapour to water . The use of this model causes, however, energy and gradient oscillations, which make it inapplicable with standard protocols of molecular dynamics simulations . The empirical solvation model which was found by other authors (von Freyberg et al., 1993, J . Mol . Biol . 233, 275-292) to give good results in the NMR structure refinement led to distortions of the ribonuclease native structure . The model based on statistical analysis of crystal structures did not perform better than minimization in vacuo.

Nippon Rinsho, 1998 Jan, 56(1), 156 - 60
{Cytomegalovirus infection and its possible treatment with herbal medicines}; Shiraki K et al.; Medicinal herbs, Geum japonicum, Syzygium aromaticum, Terminalia chebula, and Rhus javanica, with anti-herpes simplex virus therapeutic activity, inhibited replication of human cytomegalovirus(CMV) and murine CMV(MCMV) in vitro . These anti-CMV activities were examined in an MCMV infection model using immunosuppressed mice . Geum japonicum, Syzygium aromaticum, and Terminalia chebula significantly suppressed MCMV yields in lungs of treated mice compared with water treatment . Efficacy of oral treatment with 750 mg/kg/day of Geum japonicum-extract was similar to that of the intraperitoneal administration with 2 mg/kg/day of ganciclovir in increasing the body weight of infected mice and reducing the virus yield in the lungs . These herbs may be beneficial for the prophylaxis of CMV diseases in immunocompromized patients.

MMWR Morb Mortal Wkly Rep, 1998 Jan 30, 47(3), 55 - 9
Outbreaks of gram-negative bacterial bloodstream infections traced to probable contamination of hemodialysis machines--Canada, 1995; United States, 1997; and Israel, 1997.
{Electrochemical regeneration of dialysis solution in experimental and clinical conditions}
Eventov VL, Andrianova MI, Maksimenko VA, Nefedkin SI, Ostodi T.

Scientific Center of Surgery RAMN, MoscowThe authors have created a new system for electrochemical regeneration of dialysis solution and conducted 67 experiments using a model solution . Two groups of patients with terminal renal failure were treated . The regeneration system was applied in the treatment of Group 1 patients (n = 14), the traditional acetate hemodialysis procedure was used in Group 2 (n = 11) . Hemodialysis with electrochemical regeneration of dialysis fluid removed creatinine and potassium ions from critically ill patients' blood as effectively as the traditional hemodialysis procedure . During electrochemical hemodialysis, middle-molecular toxins were removed better those with the traditional one, but urea and inorganic phosphorus were eliminated slowler . Electrochemical regeneration provided continuous purification of dialysis fluid . The regenerator block can be used many times . Sodium hypochlorite ensured self-sterilization of the system . The use of electrochemical regeneration does not require water purification, water communications and dialysis concentrate, which enables the detoxification procedure to be performed outside the specially equipped rooms.

Zentralbl Hyg Umweltmed, 1996 Feb, 198(3), 215 - 25
{Tests of biodegradation of cytostatics cyclophosphamide and ifosfamide using the Closed Bottle Test (OECD 301 D)}; Kummerer K et al.; Hospital and communal waste water differ with respect to their content of specific chemical substances like disinfectants or medicaments . Some medicaments are metabolized poorly by patients after administration . Antineoplastic substances are supposed to be carcinogen, mutagen and fetotoxic and embryotoxic substances . At the present there is no information available about their behaviour in the environment . Therefore the biodegradation of ifosfamide and cyclophosphamide was investigated by using the Closed Bottle Test (OECD 301 D) . Both the structural isomeric antineoplastics were not biodegraded at a concentration of 5 mg/l in the Closed Bottle Test within 28 days ("not readily biodegradable") . A prolongation of the test up to 57 days did not alter the result . Abiotic elimination was neglectible . Cyclophosphamide and ifosfamide were not found toxic against waste water microorganisms . Further investigations about the elimination of ifosfamide and cyclophosphamide in the process of waste water treatment are necessary to get more knowledge about the possible risk connected with these substances.

Appl Radiat Isot, 1998 Mar, 49(3), 189 - 96
Potential environmental and regulatory implications of naturally occurring radioactive materials (NORM); Paschoa AS; The immense volume of naturally occurring radioactive materials (NORM) wastes produced annually by extracting industries throughout the world deserves to come to the attention of international and national environmental protection agencies and regulatory bodies . Although a great deal of work has been done in the fields of radiation protection and remedial actions concerning uranium and other mines, the need to dispose of diffuse NORM wastes will have environmental and regulatory implications that thus far are not fully appreciated . NORM wastes constitute, by and large, unwanted byproducts of industrial activities as diverse as thorium and uranium milling, niobium, tin and gold mining extraction, water treatment, and the production of oil, gas, phosphate fertilizer, coal fire and aluminum . The volumes of NORM wastes produced annually could reach levels so high that the existing low level radioactive waste (LLRW) facilities would be readily occupied by NORM if controlled disposal procedures were not adopted . On the other hand, NORM cannot just be ignored as being below radiological concern (BRC) or lower than exempt concentration levels (ECLs), because sometimes NORM concentrations reach levels as high as 1 x 10(3) kBq/kg for 226Ra, and not much less for 228Ra . Unfortunately, thus far there is not enough information available concerning NORM wastes in key industries, though the international scientific community has been concerned, for a long time now, with technologically enhanced natural radiation exposures (TENRE) . This article is written with the intention of examining, to the extent possible, the potential environmental and regulatory implications of NORM wastes being produced in selected industries.

Health Phys, 1998 Feb, 74(2), 242 - 8
Temporal and spatial variation of waterborne point-of-use 222Rn in three water distribution systems; Fisher EL et al.; Three water supply systems in Iowa were studied to examine temporal variation of 222Rn at the point of entry and the point of use . For the three towns, 71, 9, and 0% of the maximum point-of-use 222Rn concentrations were significantly higher than the point-of-entry 222Rn concentrations . Homes connected to older water mains in two of the towns had higher 222Rn concentrations than those connected to newer water mains . In one town, the waterborne 222Rn concentrations in the home were related to the home's location along an old water main . The increase in 222Rn concentrations, after the water leaves the water plant, were attributed to radium deposits in the water distribution system . In addition, the water plant's radium laden iron filters contributed 7 Bq L-1 and 60 Bq L-1 of 222Rn to the finished water in What Cheer, Iowa, and Wellman, Iowa, respectively . Backwashing schedules in the water treatment systems greatly affected point-of-entry 222Rn concentrations . The results of this study have important implications for 222Rn sampling, required for regulatory compliance.

Chemosphere, 1998 Jan, 36(1), 35 - 41
Surface water pollution by herbicides from effluents of waste water treatment plants; Nitschke L et al.; Herbicide loads of urban and rural waste water treatment plant effluents were calculated over a one-year period by measuring the herbicide concentrations in 14-day mixed samples . More than three quarters of the total herbicide load of the effluent of the rural waste water treatment plant consists of isoproturon . Particularly large amounts of this substance contribute to the total herbicide load during the main application in spring and in early autumn . The measured loads of atrazine and the increased ratio between atrazine and desethylatrazine in spring indicate that atrazine is still applied in Germany . More than 80% of the total herbicide load of the effluent of the urban waste water treatment plant consists of diuron which is mainly used in urban weed control . The results show that also effluents of urban waste water treatment plants contribute to a great extent to herbicide pollution of surface water.

Sci Total Environ, 1997 Nov 27, 207(2-3), 207 - 11
Adsorption of the cyanobacterial hepatotoxin microcystin-LR by a low-cost activated carbon from the seed husks of the pan-tropical tree, Moringa oleifera; Warhurst AM et al.; A low-cost activated carbon from the pan-tropical multipurpose tree Moringa oleifera removes the cyanobacterial hepatotoxin microcystin-LR in quantitative amounts from water in batch adsorption trials . The potential of M . oleifera seed husk carbon for cyanobacterial toxin removal in drinking water treatment in tropical countries is discussed.

J Appl Microbiol, 1997 Sep, 83(3), 347 - 52
Comparison between the evaluation of bacterial regrowth capability in a turbidimeter and biodegradable dissolved organic carbon bioreactor measurements in water; Kott Y et al.; In recent years, two different approaches to the study of biodegradable organic matter in distribution systems have been followed . The assimilable organic carbon (AOC) indicates the portion of the dissolved organic matter used by bacteria and converted to biomass, which is directly measured as total bacteria, active bacteria or colony-forming units and indirectly as ATP or increase in turbidity . In contrast, the biodegradable dissolved organic carbon (BDOC) is the portion of the dissolved organic carbon that can be mineralized by heterotrophic microorganisms, and it is measured as the difference between the inflow and the outflow of a bioreactor . In this study, at different steps in a water treatment plant, the bacterial regrowth capability was determined by the AOC method that measures the maximum growth rate by using a computerized Monitek turbidimeter . The BDOC was determined using a plug flow bioreactor . Measurements of colony-forming units and total organic carbon (TOC) evolution in a turbidimeter and of colony-forming units at the inflow/outflow of the bioreactor were also performed, calculating at all sampling points the coefficient yield (Y = cfu/delta TOC) in both systems . The correlations between the results from the bioreactor and turbidimeter have been calculated; a high correlation level was observed between BDOC values and all the other parameters, except for Y calculated from bacterial suspension measured in the turbidimeter.

Public Health Rep, 1997 Sep-Oct, 112(5), 403 - 9
Outbreak of acute fluoride poisoning caused by a fluoride overfeed, Mississippi, 1993; Penman AD et al.; OBJECTIVE: To determine the extent and confirm the cause of an August 1993 outbreak of acute fluoride poisoning in a small Mississippi community, thought to result from excess fluoride in the public water supply . METHODS: State health department investigators interviewed patrons of a restaurant where the outbreak first became manifest and obtained blood and urine samples for measurement of fluoride levels . State health department staff conducted a random sample telephone survey of community households . Public health environmentalists obtained water and ice samples from the restaurant and tap water samples from a household close to one of the town's water treatment plant for analysis . Health department investigators and town water department officials inspected the fluoridation system at the town's main water treatment plant . RESULTS: Thirty-four of 62 restaurant patrons reported acute gastrointestinal illness over a 24-hour period . Twenty of 61 households that used the community water supply reported one or more residents with acute gastrointestinal illness over a four-day period, compared with 3 of 13 households that did not use the community water supply . Restaurant water and ice samples contained more than 40 milligrams of fluoride per liter (mg/L), more than 20 times the recommended limit, and a tap water sample from a house located near the main treatment plant contained 200 mg/l of fluoride . An investigation determined that a faulty feed pump at one of the town's two treatment plants had allowed saturated fluoride solution to siphon from the saturator tank into the ground reservoir and that a large bolus of this overfluoridated water had been pumped accidentally into the town system . CONCLUSIONS: Correct installation and regular inspection and maintenance of fluoridation systems are needed to prevent such incidents.

Public Health, 1997 Sep, 111(5), 311 - 5
Health knowledge of children in Bangladesh: an exploratory study; Nath SR et al.; This article explores the relationship between selected socio-economic factors and health knowledge of children in Bangladesh . Data was generated from a representative sample survey of 2520 children aged 11-12 y and resident throughout the country . A total of six health knowledge items, all of which are very relevant to Bangladesh, were assessed in this study . Both bivariate and multivariate analysis were used for this purpose . Analysis revealed that the urban/rural residence of the child, the length of the child's schooling in years, the parental level of education and the economic status of the household was associated with the level of health knowledge of the children . To achieve the required improvement in health knowledge of Bangladeshi children this study concluded that adequate schooling of all children must be ensured by removing social barriers to this . Greater educational investment as well as quality education related to everyday life should be provided in rural areasPIP: A representative sample survey of 2520 children 11 and 12 years of age from all administrative districts in Bangladesh identified serious deficiencies in these children's knowledge of health issues . 76.7% of children were enrolled in school at the time of the survey; 13.8% had never attended school . Children were asked six health-related questions . The overall percentages of correct responses, by items, were as follows: treatment for diarrhea, 74.7%; place for defecation, 75.0%; benefits from vaccination, 36.3%; prevention of night blindness, 36.0%; water purification, 56.8%; and first aid for high fever, 57.2% . On average, the children correctly answered 3.4 items . This statistic was 4.5 among urban children compared with 3.1 among rural children . The increment in the proportion of children correctly answering each of the items was highly associated with additional years of schooling . As parental levels of education and the economic status of the households increased, so did knowledge scores . To achieve adequate levels of health knowledge, the social barriers that prevent school attendance in Bangladesh must be resolved, especially in rural areas .

Sci Total Environ, 1997 Sep 15, 203(3), 253 - 9
Trichloroethene and tetrachloroethene in ground waters of Zagreb, Croatia; Vedrina-Dragojevic I et al.; At the end of 1986 the presence of chlorinated hydrocarbons was detected in the ground water of the industrial area of Zagreb, Croatia . Concentrations of trichloroethene and tetrachloroethene were close to or exceeded maximum admissible concentrations prescribed by the Public Health Regulations for drinking water (30 micrograms/l for trichloroethene and 10 micrograms/l for tetrachloroethene) . The pumping-site situated within the area had been temporarily closed until a water-treatment plant based upon adsorption on activated carbon was built . Analysis of the results of adsorption of the investigated chlorinated hydrocarbons on activated carbon in granules confirmed a remarkably better adsorption of tetrachloroethene compared to trichloroethene . By constant monitoring and replacing of saturated carbon at the appropriate time, the concentrations of trichloroethene and tetrachloroethene in drinking water consumed by approx . 20% of the city population never exceeded maximum admissible concentrations in the course of 10 years.

Am J Trop Med Hyg, 1997 Aug, 57(2), 151 - 7
Water-borne hepatitis E virus epidemic in Islamabad, Pakistan: a common source outbreak traced to the malfunction of a modern water treatment plant; Rab MA et al.; During December 1993 and in the first three months of 1994, an explosive water-borne epidemic of hepatitis E virus (HEV) occurred in two sectors of Islamabad, Pakistan . In a survey of a population of 36,705 individuals, a total of 3,827 cases of acute icteric hepatitis were recorded with an overall attack rate (AR) of 10.4% . The etiologic role of HEV in the epidemic was proven by demonstrating anti-HEV IgG and HEV IgM in the tested serum samples . The water-borne nature of the epidemic was suggested by a study of the case distribution according to water supply . Prior to the epidemic, there had been an operational breakdown in a water treatment plant that distributed water to the affected areas while transforming its purification system from slow sand to rapid sand filtration . The primary source of water for the plant was derived from a heavily contaminated stream . The highest AR (16.3%) was observed in the areas where the source of drinking water was exclusively from the purification plant, followed by ARs of 12.4% and 5.3% for those receiving 50% and 30% or less of their water supply from the treatment plant, respectively, while the lowest AR (1.8%) was observed in the neighboring areas that did not receive water from this source . The AR was significantly higher in the group 11-30 years of age (15.3%) as compared with children less than 11 years of age (1.4%) and also relative to the group greater than 30 years of age (10.5%) . The AR among the 162 recorded pregnant females was 21.6%, which was higher than that found among nonpregnant females of child-bearing age (10.9%) . All four reported adult deaths occurred among females in their third trimester of pregnancy with a case fatality rate of 11.4%, while the other four fatal cases were newborn infants of mothers with acute icteric hepatitis . Although the aggregation of cases within households was significantly related to family size, the temporal relationship between cases in households with two or more cases revealed that 83.7% of 1,463 presumed secondary cases occurred within one month of the first case in the same household, which is not suggestive of person-to-person transmission of disease . The termination of providing water from the source was effected, which was followed by an apparent decrease in cases.

Health Phys, 1997 Aug, 73(2), 333 - 9
Behavior of Na131I and meta(131I) iodobenzylguanidine (MIBG) in municipal sewerage; Fenner FD et al.; Behavior of 131I activity in primary sludge at the Ann Arbor, Michigan, Municipal Waste Water Treatment Plant was studied in relation to known radioiodine therapy events at the University of Michigan Hospital complex . The principal compounds administered are Na131I, which has widespread use, and meta (131I) iodobenzylguanidine (MIBG), which is a compound unique to the University of Michigan, although labeled antibodies and other forms are also used in therapy and research . The objectives of the study were to determine the environmental fate of such discharges and to determine radiation exposures to workers and the public when sludges are incinerated . Approximately 17% of the MIBG activity administered in a therapy was found in the primary sludge, whereas only 1.1% of the Na131I was in sludge . When land applied, the short half life of 131I in the sludge presents few radiological health concerns; however, incineration, which is done in winter months, is assumed to release organically bound 131I to the atmosphere . Radiation doses due to incineration of sludge containing measured concentrations were calculated for a maximally exposed worker to be 1.7 microSv (0.17 mrem) of which 0.48 microSv (0.048 mrem) was due to a 2-d upset condition . For a more typically exposed worker, and a member of the public, the committed effective dose equivalents were 1.2 microSv (0.12 mrem) and 0.06 microSv (0.006 mrem), respectively, for a 22-wk incineration period with release of all radioiodine in the sludge . Transport time to the treatment plant for radioiodine was found to be much longer than that of normal sewage, possibly due to organic material in sewer lines that absorb iodine . The residence time of radioiodine in the sewer also appears to be longer than expected; whether other radioactive materials are held up the same way is not known but chemical form is surely a factor.

Public Health Rep, 1997 Jul-Aug, 112(4), 308 - 16; discussion 317-8
Radioactivity in municipal sewage and sludge; Martin JE et al.; OBJECTIVE: To determine the environmental consequences of discharges of radioactivity from a large medical research facility into municipal sewage, specifically 131I activity in sewage sludge, and the radiation exposures to workers and the public when sludges are incinerated . METHODS: The authors measured radioactivity levels in the sludge at the Ann Arbor, Michigan, Waste Water Treatment Plant following radioiodine treatments of two patients at the University of Michigan hospital complex and performed a series of calculations to estimate potential radiation doses due to releases of 131I from incineration of sewage sludge . RESULTS: Approximately 1.1% of the radioactive 131I administered therapeutically to patients was measured in the primary sludge . Radiation doses from incineration of sludge were calculated to be 0.048 millirem (mrem) for a worker during a period in which the incinerator filtration system failed, a condition that could be considered to represent maximum exposure conditions, for two nine-hour days . Calculated results for a more typically exposed worker (with the filtration system in operation and a 22-week period of incineration) yielded a committed effective dose equivalent of 0.066 mrem . If a worker were exposed to both conditions during the period of incineration, the dose was calculated to be 0.11 mrem . For a member of the public, the committed effective dose equivalent was calculated as 0.003 mrem for a 22-week incineration period . Exposures to both workers and the public were a very small fraction of a typical annual dose (about 100 mrem excluding radon, or 300 mrem with radon) due to natural background radiation . Transport time to the treatment plant for radioiodine was found to be much longer than that of a normal sewage, possibly due to absorption of iodine by organic material in the sewer lines . The residence time of radioiodine in the sewer also appears to be longer than expected . CONCLUSION: 131I in land-applied sludge presents few health concerns because sufficient decay occurs before it can reach the public however, incineration, which is done in winter months, directly releases the 131I from sewage sludge to the atmosphere, and even though exposures to both workers and the public were found to be considerably lower than 1% of natural background, incineration of sludge in a pathway for public exposure . Although 131I was readily measurable in sewage sludge, only about 1% of the radioione administered to patients was found in the sludge . The fate of the remaining radioactivity has not been established; some may be in secondary and tertiary residuals, but it is quite likely that most passed through the plant and was discharged in dilute concentrations in plant emissions . The behavior of radioiodine and other radioactive materials released into municipal seweage systems, such as those from large medical facilities, is not yet well understood.

J Virol Methods, 1997 Jul, 66(2), 263 - 8
Inactivation of rotavirus by new polymeric water disinfectants; Panangala VS et al.; Two new insoluble polymeric materials were evaluated for their efficacies in inactivating rotavirus in flowing water in a biocidal filter application . The two polymers are N-chloro and N-bromo derivatives of a poly-styrene hydantoin prepared from commercial poly-styrene . The studies were conducted for rotavirus in halogen demand-free water at pH 7.0, 25 degrees C and Environmental Protection Agency (EPA) Test Water no . 2 at pH 9.0, 4 degrees C which contained heavy halogen demand . The range of flow rates studied was 0.16-1.22 ml s-1 corresponding to contact times in the range of 4-24 s . Both of the polymers were effective in inactivating rotavirus, the N-bromo derivative providing a 4-6 log reduction under the test conditions . The materials may be useful as supplemental filters for hand-held water purification units.

Toxicon, 1997 Jul, 35(7), 1033 - 41
Stability of microcystins from cyanobacteria--IV . Effect of chlorination on decomposition; Tsuji K et al.; Microcystins, the cyclic heptapeptide toxins produced by cyanobacteria such as Microcystis, show tumor-promoting activity through inhibition of protein phosphatases 1 and 2A . They potentially threaten human health, and are increasing the world-wide interest in the health risk associated with cyanobacterial toxins . In this study, the effect of chlorination on the decomposition of microcystins-LR and -RR was examined . The toxins were easily decomposed by chlorination with sodium hypochlorite, and the decomposition depended on the free chlorine dose . In this operation, many reaction products were formed, one of which was determined to be dihydroxymicrocystin formed through the chloronium ion at the conjugated diene of Adda {3-amino-9-methoxy-10-phenyl-2,6,8-trimethyl-deca-4(E), 6(E)-dienoic acid}, followed by hydrolysis . Other products may be its stereoisomers and/or regioismers . No noxious products were detected from the chlorination process of microcystin-LR . Although these results suggested that chlorination at an adequate chlorine dose is very effective for the removal of microcystin in raw water, preoxidation of the cell itself with chlorine must be avoided, because it frequently causes toxin release from algae and produce trihalomethanes during water treatment.

Can J Microbiol, 1997 Jul, 43(7), 687 - 9
Sources of variation in isolation rate of Giardia lamblia cysts and their homogeneous distribution in river water entering a water treatment plant; Payment P et al.; The objective of this work was to determine if differences in the number of Giardia cysts measured in river water were due to the method itself, the analyst, or real differences in the distribution of these cysts in water . To minimize the methodological differences, centrifugation only was used as the primary concentration method . Differences were observed between results from different analysts and they were identified as technical errors . Once the method had been well established, cysts were found to be distributed homogeneously in the river water tested . Small differences were observed among samples collected sequentially at the same time, as well as for samples collected on different days or at different times on the same day . The differences reported in the literature in the number of Giardia cysts detected in water samples from the same site could be an artifact of the methods more than true differences in the counts.

Rev Environ Health, 1997 Apr-Jun, 12(2), 81 - 90
Drinking water chlorination by-products and cancer; Koivusalo M et al.; This review discusses the relation between by-products of drinking water chlorination and cancer in the light of present toxicological and epidemiologic evidence . During the chlorination of drinking water, a complex mixture of by-products forms from chlorine and the organic and inorganic compounds present in raw water . The quality and quantity of such compounds depend on the specific nature of the organic material in raw waters, the inorganic material in raw water, pH, temperature, other water treatment practices, and the chlorine timing and dose added . Chlorination by-products are important mainly when surface water is used for drinking water as more organic compounds are present in surface waters than in ground waters . The gastrointestinal and urinary tract are the cancer sites that are most often associated with the use of chlorinated surface water or with the quantity of chlorination by-products in the water-supply network . Yet the microbial quality of drinking water should not be compromised by excessive caution over the potential long-term effects of disinfection by-products because the risk of illness and death resulting from exposure to pathogens in untreated drinking water may be several orders of magnitude greater than the cancer risks from chlorination by-products.

Contraception, 1997 Apr, 55(4), 209 - 17
Alteration of human sperm kinematics in cervical mucus due to nonoxynol-9; Dunmire EN et al.; Traditional endpoints of the double-ended test (DET), a contraceptive screening assay used to evaluate the ability of a compound to permeate cervical mucus and inhibit sperm progression, ignore important information about sublethal effects upon sperm cells . Improved contraceptive agents may capitalize on such sublethal aspects . This study utilized a DET testing protocol that included measurement of human sperm motion characteristics as an indicator of cell function within spermicide-exposed human mucus . The currently available spermicide nonoxynol-9 (N9) was used as the test compound and was dissolved in two different delivery solutions, deionized (DI) water and saline, to evaluate the effects of the osmolarity and pH of the delivery vehicle on test results . The N9-water treatment demonstrated significantly greater activity than the N9-saline treatment in terms of all measured variables, exhibiting an apparent "biopermeation" distance approximately 3 mm further into the mucus . The DI water control treatment displayed less activity than N9-saline in terms of the vanguard penetration distance, but comparable or greater activity in terms of inhibiting kinematic variables . The saline control treatment had no effect in terms of any measured variable . Dose responses to N9 of sperm in mucus were inferred from DET results combined with direct measures of N9 diffusion . These were compared to dose responses to N9 of seminal sperm, indicating that N9 inhibits sperm motion at lower concentrations in mucus than in semenPIP: The double-ended test (DET) generally used to assess the ability of new spermicidal compounds to permeate cervical mucus and inhibit sperm progression overlooks the importance of sublethal effects on sperm cells . This study utilized a DET protocol that incorporated measurement of human sperm motion characteristics as an indicator of cell function within nonoxynol-9-exposed human mucus . Nonoxynol-9 was dissolved in both deionized water and saline to assess the effects of the osmolarity and pH of the delivery vehicle . All variables exhibited significant effects due to the nonoxynol-9-water treatment at distances as far as 13 mm into the mucus . The water treatment exhibited a biopermeation distance approximately 3 mm further into the mucus than the saline treatment and greater activity in terms of inhibiting kinematic variables . On the other hand, penetration of vanguard sperm was inhibited more by nonoxynol-9-saline . The reduction in straightline velocity of sperm was due more to a disruption in the pattern of motion than a reduction in overall sperm vigor . The measurements of sperm motility obtained in this study can be combined with information about local nonoxynol-9 concentrations in mucus to infer the dose-response of nonoxynol-9 against sperm in mucus . Overall, these findings indicate that the use of hypotonic solutions to deliver contraceptive agents can significantly increase the efficacy of the compounds through both increased transport rates and added bioactivity due to the carrier itself .

Urol Nefrol (Mosk), 1997 Mar-Apr, (2), 13 - 6
{Electrochemical regeneration of the dialyzing solution}; Eventov VL et al.; The system with electrochemical regeneration (ER) of the dialyzing solution functions as effectively as a conventional hemodialysis system: ER eliminates creatinine and potassium ions, is inferior in eliminating urea and non-organic phosphorus but superior to hemodialysis in elimination of middle-size molecular toxins . ER enables continuous purification of dialyzing solution, electrolyzer is a constant element of the regeneration system, produced by electrolyzer sodium hypochlorite warrants the system self-sterilization . ER works without systems of water purification, water communications and dialyzer concentrate that is why the procedure of detoxication can be performed outside specially equipped laboratories.

Chemosphere, 1997 Mar-Apr, 34(5-7), 989 - 97
Determination of PCDF/PCDD in sludges from a drinking water treatment plant influence of chlorination treatment; Rivera J et al.; A preliminary study to assess the origin and evolution of polichlorodibenzofurans (PCDFs) and polichlorodibenzo-p-dioxins (PCDDs) in a drinking water treatment plant (DWTP) was undertaken . Samples of coagulation sludges and exhausted granular activated carbon (GAC) were collected from a DWTP . Owing to the similar congener profiles obtained from sludges and GAC, a subsequent study of chlorination influence was carried out . Sludge samples from a treatment with and without the chlorination step were analysed . A complementary study of the PCB content was made . The results obtained did not reveal a marked influence of chlorination in the formation of PCDFs/PCDDs.

Cancer Causes Control, 1997 Mar, 8(2), 192 - 200
Drinking water chlorination and cancer-a historical cohort study in Finland; Koivusalo M et al.; Chlorination of water rich in organic material is known to produce a complex mixture of organochlorine compounds, including mutagenic and carcinogenic substances . A historical cohort study of 621,431 persons living in 56 towns in Finland was conducted in order to assess the relation between historical exposure to drinking water mutagenicity and cancer . Exposure to quantity of mutagenicity was calculated on the basis of historical information of raw water quality and water treatment practices using an empirical equation relating mutagenicity and raw water pH, KMnO4 value and chlorine dose . Cancer cases were derived from the population-based Finnish Cancer Registry and follow-up time in the study started in 1970 . Age, gender, time period, social class, and urban residence were taken into account in Poisson regression analysis of the observed numbers of cases using expected numbers of cases standardized for age and gender as a basis . Excess risks were calculated using a continuous variable for mutagenicity for 3,000 net rev/l exposure representing an average exposure in a town using chlorinated surface water . After adjustment for confounding, a statistically significant excess risk was observed for women in cancers of the bladder (relative risk {RR} = 1.48, 95 percent confidence interval {CI} = 1.01-2.18), rectum (RR = 1.38, CI = 1.03-1.85), esophagus (RR = 1.90, CI = 1.02-3.52), and breast (RR = 1.11, CI = 1.01-1.22) . These results support the magnitude of excess risks for rectal and bladder cancers found in earlier epidemiologic studies on chlorination by-products and give additional information on exposure-response concerning the mutagenic compounds . Nevertheless, due to the public health importance of water chlorination, uncertainty related to the magnitude of observed risks, and the fact that excess risks were observed only for women, the results of the study should be interpreted with caution.

Alcohol, 1997 Mar-Apr, 14(2), 117 - 24
Heme oxygenase activity and acute and chronic ethanol exposure in the hippocampus, frontal cerebral cortex, and cerebellum of the near-term fetal guinea pig; Cook MN et al.; Heme oxygenase (HO) catalyzes the oxidation of heme to produce carbon monoxide, which is considered to be a novel neuronal messenger in the brain and may play a role in neuronal development . The objective of this study was to determine the effects of in vitro, acute in vivo, and chronic in vivo ethanol exposure on HO activity in the hippocampus, frontal cerebral cortex, and cerebellum of the near-term fetal guinea pig . HO activity was determined using a gas chromatographic method to quantitate CO formation in the microsomal fraction of the homogenate of each selected brain region, incubated with saturating concentrations of heme, NADPH, and O2 . Fetal body, brain, hippocampal, and cerebellar weights were recorded . In vitro ethanol exposure (25-100 mM) did not affect hippocampal, cerebral cortical, or cerebellar HO activity of the fetal guinea pig at gestational day (GD) 62 (term, about GD 68) . Acute maternal oral administration of 4 g ethanol/kg maternal body weight at GD 62 did not affect HO activity in these three fetal brain areas compared with control fetuses (maternal administration of isocaloric sucrose or water) . For chronic daily maternal oral administration of 4 g ethanol/kg maternal body weight throughout gestation, fetal body, brain, hippocampal, and cerebellar weights were decreased at GD 62 compared with isocaloric-sucrose/pair-fed and water treatment control groups . Furthermore, isocaloric-sucrose/pair-feeding treatment decreased fetal body and brain weights compared with water treatment . Chronic in vivo ethanol exposure did not alter HO activity in the near-term fetal hippocampus, frontal cerebral cortex, or cerebellum . This is the first study of the effect of ethanol exposure on HO activity in the developing brain of any species . The data demonstrate, for ethanol CNS teratogenesis in the guinea pig manifesting as fetal brain growth restriction, there is no associated change in HO activity in the hippocampus, frontal cerebral cortex, or cerebellum.

J Community Health Nurs, 1997, 14(3), 135 - 40
The emerging recognition of cryptosporidium as a health hazard; Matukaitis JM; Cryptosporidium is the leading cause of waterborne disease in the United States . Cryptosporidiosis occurs as a result of this pathogen and is potentially fatal to the immunosuppressed population . Current water treatment standards will not eradicate the pathogen, resulting in a potential public health hazard . Congress recently passed legislation addressing cryptosporidium, and health policies are pending approval with strong support from the Centers for Disease Control . The implication for community health nursing is that nurses should take on expanded roles as social, political, and economic advocates and educators to support community actions to eradicate this pathogen.

Eur J Clin Pharmacol, 1997, 52(3), 235 - 7
Influence of an acidic beverage (Coca-Cola) on the absorption of itraconazole; Jaruratanasirikul S et al.; OBJECTIVE: To evaluate the effectiveness of Coca-Cola in enhancing the absorption of itraconazole . METHODS: Eight healthy volunteers were randomized to receive two treatment sequences in a two-way crossover design with a 1-week wash-out period separating each study treatment . Treatment 1, the control, consisted of 100 mg itraconazole with 325 ml water . Treatment II was identical to treatment I, except that itraconazole was administered with 325 ml of Coca-Cola (pH 2.5) . RESULTS: Serum itraconazole concentrations, after administration with Coca-Cola (treatment II), were higher than after administration with water (treatment I) . The mean AUC was 1.12 vs 2.02 micrograms.h.m1-1, the mean Cmax was 0.14 vs 0.31 micrograms.m1-1 and the mean tmax was 2.56 vs 3.38 h in treatments I and II, respectively . CONCLUSION: The absorption of itraconazole can be enhanced by Coca-Cola.

Annu Rev Public Health, 1997, 18, 135 - 61
Environmental ecology of Cryptosporidium and public health implications; Rose JB; Cryptosporidium has become the most important contaminant found in drinking water and is associated with a high risk of waterborne disease particularly for the immunocompromised . There have been 12 documented waterborne outbreaks in North America since 1985; in two of these (Milwaukee and Las Vegas) mortality rates in the immunocompromised ranged from 52% to 68% . The immunofluorescence antibody assay (IFA) using epifluorescence microscopy has been used to examine the occurrence of Cryptosporidium in sewage (1 to 120 oocysts/liter), filtered secondary treated wastewater (0.01 to 0.13 oocysts/liter), surface waters (0.001 to 107 oocysts/liter), groundwater (0.004 to 0.922 oocysts/liter) and treated drinking water (0.001 to 0.72 oocysts/liter) . New rules are being developed (Information Collection Rule and Enhanced Surface Water Treatment Rule) to obtain more occurrence data for drinking water systems for use with new risk assessment models . Public health officials should consider a communication program to physicians treating the immunocompromised, nursing homes, develop a plan to evaluate cases of cryptosporidiosis in the community, and contribute to the development of public policies that limit contamination of source waters, improve water treatment, and protect public health.

Occup Environ Med, 1997 Jan, 54(1), 60 - 2
Hepatitis A among workers from a waste water treatment plant during a small community outbreak; De Serres G et al.; OBJECTIVE: This is a case report describing the occurrence of hepatitis A in three workers at a waste water treatment plant during a small community outbreak involving 16 cases . CASE REPORT: The first case was a 26 year old operator who had worked in the plant for two years, the second was a 23 year old employee hired to add new biolite in the secondary treatment area . These two cases never worked together and only met two or three times before the onset of disease in the second case . The third case occurred three months later in a 34 year old ventilation mechanic . All three cases were confirmed by IgM serology and virus was recovered by polymerase chain reaction in the stools of the last two cases . Despite an extensive search for other risk factors for hepatitis A in these workers none was found . CONCLUSION: This report confirms that hepatitis A is an occupational hazard for sewage workers . The numerous potential sources of contamination associated with that occupation support the use of vaccine to provide effective prevention.

Annu Rev Med, 1997, 48, 329 - 40
Protozoal agents: what are the dangers for the public water supply?
Steiner TS, Thielman NM, Guerrant RL.
Safe and efficient treatment of drinking water has been one of the major public health advances of the twentieth century . People in developed countries generally take for granted that their water is safe to drink, a luxury the majority of the world's population does not have . The leading cause of infant mortality in the developing world is infectious diarrhea, and the prevalence of diarrheal pathogens is largely influenced by the quality and quantity of clean water available for drinking and washing . Until recently, modern water treatment had all but eliminated these concerns in developed nations . Over the past two decades, however, the safety of our water supply has been threatened by the emergence of Cryptosporidium parvum, a protozoal pathogen . The hearty oocysts of this organism survive chlorination and filtration to cause a diarrheal illness that, while unpleasant enough in healthy people, is devastating in immunocompromised individuals . The 1993 Milwaukee outbreak, in which 403,000 people developed diarrhea from drinking water that met all the updated federal safety standards, demonstrated the tremendous public health importance of this organism . While earlier attention had focused on Giardia and amebic infections, the other "emerging" protozoan besides Cryptosporidium is Cyclospora . This review discusses the protozoal pathogens, including Cryptosporidium parvum, Giardia lamblia, Entamoeba histolytica, and Cyclospora cayetanensis, that cause waterborne diarrheal outbreaks and the threats they pose to the public.

Singapore Med J, 1996 Dec, 37(6), 577 - 8
Two case reports of delayed skin burns from methylisothiazolines used in water treatment; Ng CK et al.; Kathon CG and Kathon WT are biocides containing 5-Chloro-2-Methyl-4-Isothiazoline-3-One (MCI) and 2-Methyl-4-Isothiazoline-3-One (MI) in a 3:1 ratio . These compounds are used as preservatives in skin care products and there have been many reports of allergic contact dermatitis due to Kathon used in this context . They are also widely used in industry as preservatives in metal working fluids, latex emulsions and for water treatment . Two cases of severe irritant contact dermatitis through accidental exposure to high concentrations of Kathon in industrial settings are reported to highlight the importance of worker education and the use of personal protective equipment when handling this corrosive chemical.

Environ Manage, 1996 Nov, 20(6), 955 - 61
When Biologists and Engineers Collide: Habitat Conservation Planning in the Middle of Urbanized Development
MCKINNEY LD, MURPHY R.
/ The City of Austin, Texas, is one of the fastest growing metropolitan areas in the United States . It is also in one of the most biologically diverse terrestrial ecosystems in the world: the Balcones Canyonlands . Five cave invertebrates and two species of birds that inhabit the area are listed as threatened or endangered, two species of plants are candidates for listing, several others are considered rare and of concern, and a species of the salamander has also been proposed for listing . A habitat conservation plan, of "national significance . . ." according to Secretary of Interior Bruce Babbit (Haurwitz 1996), has been under development for the last several years to conserve those endangered species through a 2400-ha system of preserves and to allow development to continue in more than 162,000 ha of surrounding area . The preserve system, comprising several units ranging in size from less than a hundred to several thousand hectares, would be bordered in many instances by developed areas . Development and maintenance of the infrastructure necessary for new and existing development, both commercial and residential, could have negated the biological value of the preserves (e.g., power-line corridors, water-treatment pipelines and facilities) . The challenge of bringing this plan to fruition illustrates the complex biological, technical, and sociological context within which habitat conservation planning may occur . Resolving resource use conflicts of this nature have several commonalities that overarch these contexts . If recognized and addressed, one may move easily and foster positive results . These commonalities can be expressed as principles such as: relying on scientists to recognize, but not solve problems; acting before a scientific consensus is achieved; including human motivation and responses as part of the system to be studied and managed; and confronting uncertainty.KEY WORDS: Endangered species; Habitat conservation plan; Resource conflicts; Biologists; Engineers

BMJ, 1996 Oct 19, 313(7063), 979 - 81
Is lead in tap water still a public health problem? An observational study in Glasgow; Watt GC et al.; OBJECTIVE: To assess the relation between tap water lead and maternal blood lead concentrations and assess the exposure of infants to lead in tap water in a water supply area subjected to maximal water treatment to reduce plumbosolvency . DESIGN: Postal questionnaire survey and collection of kettle water from a representative sample of mothers; blood and further water samples were collected in a random sample of households and households with raised water lead concentrations . SETTING: Loch Katrine water supply area, Glasgow . SUBJECTS: 1812 mothers with a live infant born between October 1991 and September 1992 . Blood lead concentrations were measured in 342 mothers . MAIN OUTCOME MEASURES: Mean geometric blood lead concentrations and the prevalence of raised tap water lead concentration . RESULTS: 17% of households had water lead concentration of 10 micrograms/l (48.3 nmol/l) or more in 1993 compared with 49% of households in 1981 . Tap water lead remained the main correlate or raised maternal blood lead concentrations and accounted for 62% and 76% of cases of maternal blood lead concentrations above 5 and 10 micrograms/dl (0.24 and 0.48 mumol/l) respectively . The geometric mean maternal blood lead concentration was 3.65 micrograms/dl (0.18 mumol/l) in a random sample of mothers and 3.16 micrograms/dl (0.15 mumol/l) in mothers whose tap water lead concentrations were consistently below 2 micrograms/l (9.7 nmol/l) . No mother in the study had a blood lead concentration above 25 micrograms/dl (1.21 mumol/l) . An estimated 13% of infants were exposed via bottle feeds to tap water lead concentrations exceeding the World Health Organisation's guideline of 10 micrograms/l (48.3 nmol/l) . CONCLUSIONS: Tap water lead and maternal blood led concentrations in the Loch Katrine water supply area have fallen substantially since the early 1980s . Maternal blood lead concentrations are well within limits currently considered safe for human health . Tap water lead is still a public health problem in relation to the lead exposure of bottle fed infants.

Adv Ren Replace Ther, 1996 Oct, 3(4), 337 - 47
Chloramine removal from water used in hemodialysis; Ward DM; Several outbreaks of hemolysis in hemodialysis patients have occurred when chloramines in the public water supply have not been adequately removed by the dialysis unit's water purification system . Chloramines are not removed by reverse osmosis or deionization, and need to be either adsorbed by filtration through granular activated carbon (GAC) or neutralized by chemical reduction by ascorbic acid (vitamin C) added to the dialysate . Chloramine levels in the incoming water can fluctuate unpredictably, and failures of both systems have occurred when chloramines have exhausted their capacity . The medical and technical issues associated with both methods are explored in detail . Safety depends on critical care in the design of the system and rigorous testing more than once daily . Most dialysis units now depend on GAC filters, two of which should be placed in series so that chloramine breakthrough can be detected after the first one, before the second one fails . Comprehensive standards in force in California have not yet been applied universally.

Antiviral Res, 1996 Oct, 32(2), 63 - 70
Prophylactic treatment of cytomegalovirus infection with traditional herbs; Yukawa TA et al.; Hot water extracts of four traditional herbs, Geum japonicum, Syzygium aromaticum, Terminalia chebula and Rhus javanica, which have been shown to have anti-herpes simplex virus (HSV) activity in vivo, were examined for anti-cytomegalovirus (CMV) activity in vitro and in vivo in this study . They inhibited replication of human CMV and murine CMV (MCMV) in vitro . These anti-CMV activities in vivo were examined in an MCMV infection model using immunosuppressed mice . Mice were subcutaneously treated with various doses of cyclosporine, and immunosuppression and MCMV infection were monitored by suppression of antibody production and virus yield in the lung, respectively . Each herbal extract was orally administered to mice treated with 50 mg/kg of cyclosporine from a day before intraperitoneal infection, and the efficacy of herbs was evaluated by the reduction in the virus yield in the lung . Among them Geum japonicum, Syzygium aromaticum, and Terminalia chebula significantly suppressed MCMV yields in lungs of treated mice compared with water treatment . Efficacy of oral treatment with 750 mg/kg per day of Geum japonicum extract was similar to that of the intraperitoneal administration of 2 mg/kg per day of ganciclovir in increasing the body weight of infected mice and reducing the virus yield in the lungs . These herbs may be beneficial for the prophylaxis of CMV diseases in immunocompromised patients.

Tsitol Genet, 1996 Sep-Oct, 30(5), 76 - 81
{The products of water chlorination as inducers of gene mutations}; Dugan AM; Experimental data on water mutagenicity from Dnepro technological chain of pipe-line water purification were obtained using Ames express method of gene mutation induction in histidine-dependent strains of Salmonella typhimurium series TA (TA 98 and TA 100) . It was shown that water mutagenicity depended on the level of water pollution by chemical substances in the river Dnieper and the use of chlorine for water disinfection.

Gig Sanit, 1996 Sep-Oct, (5), 3 - 6
{Coliphages as indicators of viral pollution of water supply}; Nedachin AE et al.; The paper presents the data of Russian and foreign authors, as well as these author's findings of the significance of coliphages as indicators of viral contamination of drinking water . Coliphages may be used as indicators of viral drinking water contamination and for evaluation of the efficiency of drinking water purification in waterworks.

Zentralbl Bakteriol, 1996 Sep, 285(1), 106 - 12
PCR-mediated DNA fingerprinting of atypical campylobacter strains isolated from surface and drinking water; Jacob J et al.; This study shows that typing through polymerase chain reaction (PCR) can be used to differentiate between strains of Campylobacter and Arcobacter, whereas by means of conventional biotyping Arcobacter might be identified as atypical Campylobacter . Microaerophilic "campylobacter-like" organisms were isolated from several drinking water treatment plants as well as environmental sources . The strains were characterized by biotyping and PCR amplification of Campylobacter flaA/flaB and 16s-rRNA Arcobacter butzleri-specific genes.

Mol Chem Neuropathol, 1996 Sep, 29(1), 53 - 66
Alterations in the neutral proteinase activities of central and peripheral nervous systems of acrylamide-, carbon disulfide-, or 2,5-hexanedione-treated rats; Gupta RP et al.; Proteinases are widespread in neuronal or nonneuronal eukaryotic cells . They are suggested to play an important role in the turnover of proteins in neuronal perikaryon and axon, and digestion of the transported cytoskeletal proteins in synaptic terminals . We examined the effect of acrylamide (50 mg/kg, ip), carbon disulfide (700 ppm, 9 h, 7 d a week), and 2,5-hexanedione (2,5-HD) (1% in drinking water) treatment of rats on mCANP (2 mM Ca2+), microCANP (0.1 mM Ca2+), and CINP (Ca(2+)-independent) activity in telencephalon + diencephalon (FB), rhombencephalon + mesencephalon (LB), spinal cord (SC), and sciatic nerve (SN) . The proteinase activity was determined in the 30,000g supernatant fraction of tissues using 14C-methylated casein as the substrate . mCANP activity in FB, LB, and SC was inhibited only by acrylamide . Acrylamide or 2,5-HD treatment had no effect on microCANP and CINP activities of SN, whereas carbon disulfide enhanced microCANP after 15 d and CINP activity after 10 d . It is suggested that alteration in in vitro calpain activity shown by these chemicals may not be directly related to their neurotoxic effect . However, calpain may still be playing a role in this polyneuropathy by alteration in activity through inflow of Ca2+, release of Ca2+ from intracellular organelles, or other factors . Modification of cytoskeletal proteins making them more susceptible to proteases and the role of some other proteinase is also possible.

Health Phys, 1996 Sep, 71(3), 286 - 9
The determination of radioisotope levels in municipal sewage sludge; Miller WH et al.; Sludge samples from 25 municipal waste water treatment plants have been analyzed to determine the level of environmentally present, man-made, gamma-ray emitting radioisotopes . Samples were freeze dried and separated into dried sludge, liquid-soluble and liquid-insoluble components . These were counted in the low background level, whole body counter at Missouri University using a standard intrinsic-Germanium spectrometer . After freeze drying, the liquid effluents from the samples were not found to have statistically significant levels of radioactivity . Using log-normal analysis, the dried sludge was found to have 0.0016 +/- 0.0022 Bq g-1 (0.04 +/- 0.06 pCi g-1) of 137Cs and 0.001 +/- 0.003 Bq g-1 (0.03 +/- 0.08 pCi g-1) of 60Co . These data can be used to determine if sewage effluents from nuclear facilities have levels of radioactivity above that expected from the environment.

Biodegradation, 1996 Aug, 7(4), 287 - 95
Spectroscopic and elemental investigation of microbial decomposition of aquatic fulvic acid in biological process of drinking water treatment; Shin HS et al.; As humic substances left in treated water tend to form trihalomethans during chlorination, their removal in water treatment processes is a significant concern for drinking water supplies . One of the removal technologies, the biofilm reactor is studied for the microbial decomposition of aquatic fulvic acid (AFA) . The AFA is characterized by elemental analysis . UV-Vis, 13C-NMR, and IR spectroscopic methods . The spectroscopic and elemental investigation was capable of characterizing the microbial decomposition of AFA . Biologically treated fulvic acid was in a more oxidized state; its spectra displayed a higher degree of condensation of aromatic constituents than influent fulvic acid . Microbial degradation of AFA was more active in the low molecular weight fractions and intensively occurred in the aliphatic fraction.

Alcohol Clin Exp Res, 1996 Aug, 20(5), 948 - 53
Effect of chronic maternal ethanol administration on nitric oxide synthase activity in the hippocampus of the mature fetal guinea pig; Kimura KA et al.; Nitric oxide is a novel messenger that is involved in neuronal cell-cell communication and seems to play a neurotrophic role in normal brain development . Chronic prenatal ethanol exposure can produce central nervous system (CNS) teratogenesis, in which one of the target sites is the hippocampus . The main objective of our study was to test the following hypothesis: chronic maternal administration of an ethanol dosage regimen that produces CNS teratogenesis decreases nitric oxide synthase (NOS) activity in the fetal hippocampus . The ontogeny of NOS activity in the hippocampus of the developing guinea pig was further elucidated at two prenatal and two postnatal ages . The effects of chronic maternal oral administration of 4 g of ethanol/kg maternal body weight/day, isocaloric sucrose and pair feeding, or water {given as two equally divided doses 2 hr apart from gestational day (GD) 2 to GD 61} on body, brain, and hippocampal weights and hippocampal NOS activity were determined in the mature fetal guinea pig at GD 62 (term, about GD 68) . NOS activity in the 25,000 x g supernatant fraction of hippocampal homogenate was measured using an optimized radiometric assay, based on the oxidation of L-{14C}arginine to L-{14C}citrulline . For the chronic ethanol regimen, the maternal blood ethanol concentration at 1 hr after the second divided dose on GD 57 was 157 +/- 45 mg/dl . Chronic maternal administration of ethanol decreased fetal body, brain, and hippocampal weights, compared with the isocaloric-sucrose/pair-fed and water treatment groups . The rate of L-{14C}citrulline formation and NOS activity in the fetal hippocampus were decreased in the ethanol treatment group, compared with the isocaloric-sucrose/ pair-fed and water treatment groups . There was no difference in the rate of L-{14C}citrulline formation, NOS activity, and fetal hippocampal and body weights between the isocaloric-sucrose/pair-fed and water treatment groups; however, fetal brain weight was decreased in the isocaloric-sucrose group, compared with the water group . Data of this study support the research hypothesis by demonstrating that chronic maternal administration of ethanol decreases fetal hippocampal NOS activity that is correlated with restricted growth of this brain region.

J Occup Environ Med, 1996 Aug, 38(8), 759 - 64
Occupational exposure of water-plant operators to high concentrations of radon-222 gas; Fisher EL et al.; Water-plant operators may be exposed to high airborne radon-222 (222Rn) concentrations created when 222Rn gas transfers from water to air during the water treatment processes . To evaluate this hazard, we placed yearlong alpha-track radon detectors in 31 water plants . The geometric mean of the annual average airborne 222Rn concentrations was 3.4 pCi L-1 (126 Bq m-3), with a maximum of 133 pCi L-1 (4921 Bq m-3) . We assessed the short-term temporal variability of 222Rn by monitoring four water plants continuously for a 3- to 6-day period . Cumulative working level months were estimated for the time workers were in the water plants . Because airborne 222Rn concentrations in water plants can reach levels considered unsafe for underground miners, it would be prudent to monitor airborne 222Rn concentrations in water plants which aerate water as part of their treatment process.

Appl Environ Microbiol, 1996 Jul, 62(7), 2508 - 12
A simple filtration method to remove plankton-associated Vibrio cholerae in raw water supplies in developing countries; Huo A et al.; Plankton to which cells of Vibrio cholerae O1 and/or O139 were attached was introduced into 0.5% Instant Ocean microcosms maintained at 25 degrees C . The bulk of the plankton and associated particulates was removed with a filter constructed from either nylon net and one of several different types of sari material, the latter being very inexpensive and readily available in villages in Bangladesh, where V . cholerae is endemic . V . cholerae was enumerated before and after filtration to evaluate the efficiency of the filtration procedure . The results obtained indicate that 99% of V . cholerae, i.e., those cells attached to plankton, were removed from the water samples . Epidemic strains of V . cholerae O1 and O139 from various geographical sources, including Bangladesh, Brazil, India, and Mexico, were included in the experiments . Removal of vibrios from water by this simple filtration method was found to yield consistent results with all strains examined in this study . Thus, it is concluded that a simple filtration procedure involving the use of domestic sari material can reduce the number of cholera vibrios attached to plankton in raw water from ponds and rivers commonly used for drinking . Since untreated water from such sources serves as drinking water for millions of people living in developing countries (e.g., Bangladesh), filtration should prove effective at reducing the incidence and severity of outbreaks, especially in places that lack fuel wood for boiling water and/or municipal water treatment plants . The results of this study provide the basis for determining such reductions, which are to be carried out in the near future.

Int J Parasitol, 1996 Jun, 26(6), 637 - 46
Nucleic acid stains as indicators of Giardia muris viability following cyst inactivation; Taghi-Kilani R et al.; A reliable viability assay for Giardia is required for the development of disinfection process design criteria and pathogen monitoring by water treatment utilities . Surveys of single-staining nucleic acid dyes (stain dead parasites only), and double-staining vital dye kits from Molecular Probes (stain live and dead parasites) were conducted to assess the viability of untreated, heat-killed, and chemically inactivated Giardia muris cysts . Nucleic acid staining results were compared to those of in vitro excystation and animal infectivity . Nucleic acid stain, designated as SYTO-9, was considered the best among the single-staining dyes for its ability to stain dead cysts brightly and its relatively slow decay rate of visible light emission following DNA binding . SYTO-9 staining was correlated to animal infectivity . A Live/Dead BacLight was found to be the better of 2 double-staining viability kits tested . Logarithmic survival ratios based on SYTO-9 and Live/Dead BacLight were compared to excystation and infectivity results for G . muris cysts exposed to ozone or free chlorine . The results indicate that SYTO-9 and Live/Dead BacLight staining is stable following treatment of cysts with chemical disinfectants.

Am J Trop Med Hyg, 1996 Jun, 54(6), 549 - 53
Reduction of risk of watery diarrhea with point-of-use water filters during a massive outbreak of waterborne Cryptosporidium infection in Milwaukee, Wisconsin, 1993; Addiss DG et al.; The occurrence of a massive waterborne outbreak of Cryptosporidium infection in Milwaukee, Wisconsin provided an opportunity to evaluate the effectiveness of point-of-use home water filters in preventing diarrheal illness associated with Cryptosporidium infection . Of 155 filter owners who responded to a televised request to contact the City of Milwaukee Health Department, 99 (64%) completed a self-administered questionnaire regarding their sources of drinking water, the characteristics of their home water filters, and diarrheal illness during the outbreak . Diarrhea among respondents was independently associated with residence in southern or central Milwaukee (the area served by the implicated South water treatment plant), having a home water filter with a pore diameter of greater than 1 micron, and drinking unfiltered tap water in a public building in southern Milwaukee . Among residents of southern and central Milwaukee, two (18%) of 11 persons who drank only submicron-filtered water at home and who did not drink unfiltered South plant water at work had watery diarrhea, compared with 50% (n = 2), 63% (n = 35), and 80% (n = 15) who reported drinking South plant water that was unfiltered or passed through a filter with a pore diameter > 1 micron at work only, home only, or both home and work, respectively (P = 0.02) . The data indicate that use of submicron point-of-use water filters may reduce risk of waterborne cryptosporidiosis.

J Emerg Med, 1996 May-Jun, 14(3), 345 - 50
Hospitals respond to water loss during the Midwest floods of 1993: preparedness and improvisation; Peters MS; The Midwest floods of 1993 presented multiple emergency preparedness challenges to the six metropolitan medical centers in Des Moines, Iowa . As floodwaters overcame the Des Moines Water Treatment Plant, medical centers were faced with the task of responding to imminent water loss and its associated impact on patient care services and facility operations . Many clinical services were cancelled or diverted to alternate facilities . Ancillary resources were identified and implemented to maintain essential operations . Through effective emergency preparedness and creative improvisation, medical centers were able to overcome the initial crisis, sustain primary services, and ensure continued quality patient care . The article describes how sudden and prolonged water loss affected Des Moines hospitals . It also discusses aspects of hospital emergency preparedness that contributed to successful response.

Arch Intern Med, 1996 Apr 8, 156(7), 807 - 10
'Travelers' thyrotoxicosis' . Transitory thyrotoxicosis induced by iodinated preparations for water purification; Liel Y et al.; Two young adults presented with thyrotoxicosis after increased iodide ingestion in the course of backpacking trips to Central and South America, during which each of them used an iodinated preparation for water purification . In both cases, serologic tests were positive for antithyroid peroxidase antibodies, and one had a family history of immune thyroid disease . We suggest that in these two cases the condition was a variant of iodide-induced thyrotoxicosis, reflecting an inadequate response to iodide excess in association with a presumed preexisting asymptomatic immune thyroid disease . This observation adds a new consideration for travelers' consultation.

Biodegradation, 1996 Apr, 7(2), 151 - 64
Complete degradation of xenobiotic surfactants by consortia of aerobic microorganisms; van Ginkel CG; Linear alkylbenzene sulphonates are primarily attacked via a hydroxylation of the alkyl chain from the methyl group followed by beta-oxidation . The alkyl chain is metabolized by pure cultures to give sulphophenyl carboxylates which accumulate in the medium . In mixed culture, other microorganisms are capable of degrading sulphophenyl carboxylates . Formation of ethylene glycol monosulphates as major products of alkyl ethoxy sulphates demonstrates that the ether bonds are cleaved . The bacteria involved in growing on the alkyl chain are unable to utilize the hydrophilic moiety . This hydrophilic moiety, in turn, is degraded by other microorganisms . The degradation of alkylphenol ethoxylates and highly branched alcohol ethoxylates proceeds by shortening the polyoxyethylene chain leaving the hydrophobic part of the molecule . The biodegradation of linear alcohol ethoxylates and ethoxylated fatty amines is initiated by a central cleavage or omega-oxidation . Subsequent oxidation of the alkyl chains results in the production of polyethylene glycols and secondary ethoxylated amines . Both polar moieties are metabolized by other microorganisms . Degradation of alkyltrimethylammonium salts and alkylamines is initiated by a cleavage of the Calkyl-N bond . The central fission leads to the formation of alkanals which are readily converted by beta-oxidation . The alkyl chain-utilizing bacteria are not able to degrade the methylamines . The methylamines, in turn, are subject to biodegradation by methylotrophs . The limited metabolic capacities of pure cultures of microorganisms utilizing surfactants point to the requirement of consortia to degrade surfactants completely . Complete degradation of surfactants is accomplished by mixed cultures of microorganisms constructed on the basis of synergistic and commensalistic relationships . However, degradation of a surfactant by one member of a commensalistic consortium may lead to the production of toxic or non-toxic metabolites . Waste water treatment without the build up of such metabolites can be achieved in plants operated with sludge retention times that are suitable for maintaining all microorganisms of the consortium . In contrast, in natural ecosystems the introduction of a surfactant may result in a transient formation of a metabolite.

Adv Ren Replace Ther, 1996 Apr, 3(2), 137 - 46
Tearing down the barriers to daily home hemodialysis and achieving the highest value renal therapy through holistic product design; Kenley RS; Renal therapy value can be defined as the ratio of outcomes achieved by a dialytic therapy to the total cost of providing that therapy . One desirable goal of any dialysis modality would be the achievement of maximum value . Unfortunately, with conventional hemodialysis and peritoneal dialysis modalities, improving outcomes has always been linked to a simultaneous increase in costs, thereby leaving value relatively unchanged . However, a new modality, daily home hemodialysis, finally may allow this linkage to be broken . The outcomes are dramatically improved as a result of a higher quantity and quality of dialysis dose resulting from the greater frequency of treatments . The costs can be reduced by minimizing the consumed items, avoiding the labor and overhead of dialysis clinics, and reducing the costs associated with morbidity . Provision of this therapy is, however, predicated on the availability of instrumentation designed specifically for it because conventional equipment designed for in-center use is not suitable . By starting with a clean sheet of paper and incorporating such features as insitu reuse of the entire extracorporeal circuit, remote telemonitoring, automated system disinfection, and integrated water purification, most of the impediments to performing this modality can be overcome.

Adv Ren Replace Ther, 1996 Apr, 3(2), 124 - 32
Daily home hemodialysis: a hybrid of hemodialysis and peritoneal dialysis; Twardowski ZJ; Despite that routine home hemodialysis, performed with thrice weekly frequency, had provided the best clinical results of any dialysis modality, it has been losing competition to center hemodialysis and home peritoneal dialysis . The main reason for this paradox is a lack of suitable equipment for home hemodialysis . Contrary to peritoneal dialysis, which is easy to learn and perform without need for a helper, home hemodialysis is difficult because the kidney machines are not designed for home therapy . Daily hemodialysis provides even better results than routine home hemodialysis . Several studies showed excellent intradialytic and interdialytic tolerance . In spite of these results the method is used only in a few centers . There are two major reasons for this incongruity: time requirement for the patient and the cost for the provider . With more frequent dialysis, more time is spent on machine setup, tear down, and cleaning . If supplies are not reused, the cost of dialysis increases substantially with increased frequency of dialysis . Daily home hemodialysis may become practical with a new machine . Three components seem crucial for this device: a built-in water treatment system; a simple, small, positive pressure, single pass, batch dialysate system; and a reusable extracorporeal circuit, automatically cleaned and disinfected daily . Daily home hemodialysis performed with the new artificial kidney system may be considered as a hybrid of hemodialysis and peritoneal dialysis . High efficiency is taken from hemodialysis; simplicity is taken from peritoneal dialysis.

Rhinology, 1996 Mar, 34(1), 14 - 7
Histological changes in the nasal mucosa after hot-water irrigation . An animal experimental study; Stangerup SE et al.; Many years ago the treatment of posterior epistaxis was irrigation with hot water through the bleeding nose cavity, and the treatment was successful in many cases . The aim of this study is to explain how "hot-water irrigation" can cause haemostasis . Twenty-four rabbits were divided into 12 groups and their noses were irrigated for 5 min with hot water at temperatures ranging from 40-60 degrees C . After irrigation, the nose was fixed, sliced, stained, and evaluated blindly by a pathologist . The morphological changes-narrowing of intranasal lumen, vasodilation and stasis, extravasation of erythrocytes, and epithelial necrosis-were recorded . No changes were recorded after irrigation with water of 40-44 degrees C . Only light changes were present in the 46 degrees C group . Vasodilation occurred at a temperature of 48 degrees C or higher . From 48 degrees C, oedema of the mucosa and subsequent narrowing of the intranasal lumen was seen . Severe changes including epithelial necrosis, were found only in the groups treated with 52 degrees C or higher . The results of the study indicate that the haemostatic effect of hot water treatment for epistaxis may be caused by: (1) oedema and narrowing of the intranasal lumen, (2) vasodilation of the mucosal vessels, and (3) cleaning of the nose from blood coagulates.

Ann Intern Med, 1996 Mar 1, 124(5), 459 - 68
Cryptosporidiosis: an outbreak associated with drinking water despite state-of-the-art water treatment; Goldstein ST et al.; OBJECTIVE: To determine the magnitude and source of an outbreak of cryptosporidiosis among persons with human immunodeficiency virus (HIV) infection and to determine whether the outbreak extended into the immunocompetent population . DESIGN: Matched case-control study and environmental investigation . SETTING: Clark County, Nevada . PARTICIPANTS: Adults with HIV infection (36 case-patients with laboratory-confirmed Cryptosporidium parvum infection and 107 controls), matched by physician or clinic and by CD4+ cell count category . MEASUREMENTS: Potential risk factors for infection, death rates, and data on water quality . RESULTS: Review of surveillance and microbiology records identified 3 cases of cryptosporidiosis in 1992 (the first year that cryptosporidiosis was reportable in Nevada), 23 cases in 1993, and 78 cases in the first quarter of 1994 . Of the 78 laboratory-confirmed cases in the first quarter of 1994, 61 (78.2%) were in HIV-infected adults . Of these 61 adults, 32 (52.5%) had died by 30 June 1994; at least 20 of the 32 (62.5%) had cryptosporidiosis listed on their death certificates . In the case-control study, persons who drank any unboiled tap water were four times more likely than persons who drank only bottled water to have had cryptosporidiosis (odds ratio, 4.22 {95% Cl, 1.22 to 14.65}; P = 0.02) . For persons with CD4+ cell counts less than 100 cells/mm3, the association between tap water and cryptosporidiosis was even stronger (odds ratio, 13.52 {Cl, 1.78 to 102.92}; P = 0.01) . Additional data indicate that this outbreak also affected persons who were not infected with HIV . No elevated turbidity values or coliform counts and no Cryptosporidium oocysts were found in testing of source (Lake Mead) or finished (treated) water during the study period, but so-called presumptive oocysts were intermittently found after the investigation in samples of source water, filter backwash, and finished water . CONCLUSIONS: A cryptosporidiosis outbreak was associated with municipal drinking water, despite state-of-the-art water treatment and water quality better than that required by current federal standards . This outbreak highlights the importance of surveillance for cryptosporidiosis and the need for guidelines for the prevention of water-borne-Cryptosporidium infection among HIV-infected persons.

J Chromatogr A, 1996 Feb 2, 723(1), 27 - 34
Determination of short-chain aliphatic, oxo- and hydroxy-acids in drinking water at low microgram per liter concentrations; Peldszus S et al.; A fast and reliable ion chromatography method has been developed and applied to study the formation and consumption of organic acid ozonation by-products in a drinking water treatment plant . Water samples are injected directly into the ion chromatograph using a large sample loop (740 mu l) without any sample preparation step other than possibly filtration . Organic and inorganic anions are determined by separation on a high-capacity anion-exchange column followed by conductivity detection . The average recovery for the organic acids investigated (beta-hydroxybutyric, acetic, glycolic, butyric, formic, alpha-ketobutyric and pyruvic acid) ranged from 96 to 105%, and their method detection limits ranged from 1 to 5 mu g/l . When applied to samples taken from a drinking water treatment plant, the method proved to be reliable.

Am J Public Health, 1996 Feb, 86(2), 237 - 9
Temporal variation in drinking water turbidity and diagnosed gastroenteritis in Milwaukee; Morris RD et al.; Daily counts of diagnosed gastroenteritis (gastrointestinal events) in Milwaukee County, Wisconsin, from January 1992 through April 1993 were compared with reported daily turbidity from the two drinking water treatment plants serving the county . Turbidity in both plants was associated with an increased number of gastrointestinal events even after exclusion of a major documented outbreak of cryptosporidiosis . During the 434-day period prior to the outbreak, an increase in turbidity of 0.5 nephelometric turbidity units at one of the plants was associated with relative risks for gastrointestinal events of 2.35 among children (95% confidence interval {CI} = 1.34, 4.12) and 1.17 among adults (95% CI = 0.91, 1.52).

Rocz Panstw Zakl Hig, 1996, 47(3), 247 - 56
{Nitrilotriacetic acid (NTA)--properties and environmental behavior . II . Ecotoxicity and biodegradability of NTA in the environment}; Malanowska M et al.; The results are described of studies on the effects of NTA on aqueous organisms and crops . The results show that NTA at concentrations determined in natural water systems causes no disturbances of the equilibrium in ecosystems . The conditions of the NTA biodegradation process in communal sewage and in surface waters and the effects of the processes taking place in water treatment systems destined for providing drinking water on NTA degradation are described . In a summary of the results of monitoring studies conducted in countries where NTA has been accepted for widespread use in washing powders the problems are stressed which will require solving before the decision is made of permission of NTA use in Poland . As of now, there are no full data making possible permission of using NTA in products of household chemistry.

Magn Reson Imaging, 1996, 14(7-8), 983 - 4
Interaction of nonionic polymers at a clay interface; Grandjean J et al.; The structure and dynamics at the interface of swelling clays (smectites) are crucial to such diverse applications as drilling for oil, cosmetics, paints, water treatment, or chemical reactions . From our previous NMR studies on clay suspensions, we have shown how the orientation of interfacial molecules is affected by the clay structure1, by the nature of counterions 2, or by the composition of the liquid phase3 . These results have been mainly obtained from the analysis of residual quadrupolar splittings of nuclei from interfacial species . In this work, we report our studies on a clay montmorillonite suspended in aqueous solutions of non ionic polymers . The polymer perturbs the structure within the interfacial region as deduced from the variations of the splittings of water quadrupolar nuclei and of sodium-23 relaxation parameters in terms of the polymer concentration . Proton self-diffusion coefficients and carbon-13 relaxation times are measured to describe the influence of the clay on the polymer mobility . The dependence of the polymer nature on these parameters is also investigated.

Nephrol Dial Transplant, 1996, 11 Suppl 2, 92 - 7
Adequacy of dialysis: trace elements in dialysis fluids; D'Haese PC et al.; A number of considerations suggest that trace element disturbances might occur in dialysed patients . These must at least in part be ascribed to the dialysis treatment itself during which these constituents may either be transferred to or removed from the patient . Tap water must be considered as the main source of dialysate trace metal contamination . These can adequately be removed during water treatment provided that, in addition to softening and deionization, reverse osmosis is available . However, even in the presence of the latter devices the possibility of serious contamination of the dialysis fluids leading to either chronic or acute intoxications still exists . The addition of chemical concentrates may also contribute to the increased concentrations of a number of trace metals . The toxic effects of aluminium in dialysis patients are well known and at the present time the element is still responsible for the greater part of trace metal-related problems in dialysis patients . Hence, the need for regular monitoring of aluminium cannot be ruled out at present . Strategies for diagnosis and treatment of aluminium overload have been updated . Recent studies demonstrated the efficacy of low desferrioxamine doses in diagnosis and treatment of aluminium overload, and optimal schedules for administration of the chelator and duration of treatment have been presented . Recently, in an epidemiological survey serum silicon concentrations in dialysis patients were found to be increased up to 100-fold compared to subjects with normal renal function . Moreover, it was noted that silicon concentrations in the dialysis population differ from one centre to another and that increased levels are due to either the use of silicon-contaminated dialysis fluids or an increased oral intake of the element originating from a high silicon content in the drinking water . Besides aluminium and silicon, a transfer towards the patients during dialysis has also been reported for a number of other elements including copper, zinc, nickel, strontium and chromium . The possible consequences of dialysate contamination with these elements will briefly be dealt with in the present paper . In contrast to trace metal accumulation, removal of trace metals during dialysis may at least in part contribute to the relative deficiency of particular essential elements . Selenium deficiency has repeatedly been observed . In view of the element's well-known essential role in glutathion peroxidase activity and the association of its deficiency with the development of some malignant diseases, further studies on the clinical impact of decreased serum selenium in dialysis patients are worthwhile . In conclusion, trace metal dialysate contamination/ depletion may contribute to the disturbed trace element concentration in dialysis patients . Aluminium accumulation is still an important problem in clinical nephrology . The clinical importance of the accumulation/ deficiency of trace elements other than aluminium is not yet fully understood and deserves further investigationPublication Types:

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