Wastewater

Int J Syst Bacteriol, 1996 Oct, 46(4), 1056 - 64
Sulfobacillus disulfidooxidans sp . nov., a new acidophilic, disulfide-oxidizing, gram-positive, spore-forming bacterium; Dufresne S et al.; An acidophilic, disulfide-oxidizing, mesophilic, aerobic bacterium was isolated from wastewater sludge . The new organism is a gram-positive sporulated rod . It can use elemental sulfur and pyrite as sole energy sources and grows on organic substrates such as glutamate and glucose . It also grows on the following organic sulfur substrates: oxidized and reduced glutathione, cysteine, cystine, and dithio(bis)benzothiazole and clearly shows a preference for disulfide bond-containing substrates . The optimal pH of growth is between 1.5 and 2.5, depending on the substrate used, and the growth temperature range varies from 4 to 40 degrees C, with an optimal value at 35 degrees C . The G + C chromosomal DNA content was measured at 53 +/- 1 mol% . Phylogenetic analysis of 16S genes coding for rRNA sequences places the new isolate in the genus Sulfobacillus . In addition, unique phenotypic and physiologic characteristics and DNA homology values assign the isolate to a new species in the genus . Therefore, this new isolate has been named Sulfobacillus disulfidooxidans and has been assigned ATCC number 51911.

Ecotoxicol Environ Saf, 1996 Aug, 34(3), 223 - 7
Winter stress syndrome: an important consideration for hazard assessment of aquatic pollutants; Lemly AD; Winter Stress Syndrome (WSS) is a condition of severe lipid depletion in fish brought on by external stressors in combination with normal reductions in feeding and activity during cold weather . Fish can develop this syndrome in response to chemical stressors, such as water pollutants, or biological stressors such as parasites . Substantial mortality can result, potentially changing year-class strength and population structure of the affected species and altering community-level ecological interactions . Aquatic contaminants should be evaluated in the context of seasonal metabolic changes that normally occur in test organisms . WSS could be an important, but as yet unquantified, cause of mortality in many circumstances . Wastewater discharges may pose a greater toxic threat to fish during winter than at other times of the year . A comprehensive protocol for aquatic hazard assessment should include testing for WSS.

Environ Manage, 1996 Jul, 20(4), 487 - 95
Salt Enrichment of Municipal Sewage: New Prevention Approaches in Israel
Weber B, Avnimelech Y, Juanico M.
Wastewater irrigation is an environmentally sound wastewater disposal practice, but sewage is more saline than the supplied fresh water and the salts are recycled together with the water . Salts have negative environmental effects on crops, soils, and groundwater . There are no inexpensive ways to remove the salts once they enter sewage, and the prevention of sewage salt enrichment is the most immediately available solution . The body of initiatives presently structured by the Ministry of the Environment of Israel are herein described, with the aim to contribute to the search for a long-term solution of salinity problems in arid countries . The new initiatives are based on: (1) search for new technologies to reduce salt consumption and discharge into sewage; (2) different technologies to cope with different situations; (3) raising the awareness of the public and industry on the environmental implications of salinity pollution; and (4) an elastic legal approach expressed through new state-of-the-art regulations . The main contributor to the salinity of sewage in Israel is the water-softening process followed by the meat koshering process . Some of the adopted technical solutions are: the discharge of the brine into the sea, the substitution of sodium by potassium salts in the ion-exchangers, the construction of centralized systems for the supply of soft water in industrial areas, the precipitation of Ca and Mg in the effluents from ion-exchangers and recycling of the NaCl solution, a reduction of the discharge of salts by the meat koshering process, and new membrane technology for salt recovery.

J Chromatogr A, 1996 May 10, 733(1-2), 511 - 22
Wastewater from the manufacture of rubber vulcanization accelerators: characterization, downstream monitoring and chemical treatment; Puig A et al.; The content of wastewater resulting from the manufacture of rubber antioxidants and accelerators by a factory situated in the Ebro basin (Spain) has been determined using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID) . The change in the pollutants was studied in the riverbed via two modules which continuously gathered pollutants on various solid supports (activated carbon and XAD-2 resins) . These modules were located in Bocal Station, lying a further 100 km downstream from the factory, and from the Zaragoza water supply . Forty-six different compounds were identified at Bocal Station, the majority resulting from the production of rubber additives . Due to the immunity of different waste substances, and to the toxic nature of some, we studied their reaction when subjected to techniques of chemical oxidation using ozone.

Kansenshogaku Zasshi, 1996 Feb, 70(2), 132 - 40
{An outbreak of waterborne Cryptosporidiosis in Kanagawa, Japan}; Kuroki T et al.; An outbreak of diarrhea due to infection with Cryptosporidium occurred among the staff members and customers who visited one of the 10 public houses or a dancing school in a building in Hiratsuka, Kanagawa Prefecture, at the end of summer in 1994 . The epidemiological surveys by a questionnaire revealed that 461 out of 736 persons investigated complained of cholera-like or flu-like illness . The clinical manifestations included mucous and/or watery diarrhea (96.7%), abdominal pain (61.6%), fever (54.2%: lower than 39 degrees C = 84.1%, higher than 39 degrees C = 15.9%), malaise (37.1%), nausea (32.8%) and headache (29.3%) . The polluted drinking water was strongly suspected to be the immediate cause of infection . Although several species of pathogenic bacteria were isolated both from stool and water samples, they were not supposed to be linked to the outbreak . No known enteropathogenic virus was found in either of the samples . Oocysts of Cryptosporidium parvum were identified in 12 (48.0%) of the 25 stool samples . The oocysts were also found in tap water and other water samples from a receiving tank which was directly connected with the public waterworks, and an elevated tank on the roof, a wastewater pits, a soil pit and artesianspring water tank . These tanks and pits except for the elevated tank were built adjucent to each other on an underground floor of the building . These tanks and pits were connected with openings in the upperpart of the tank walls . These openings might have functioned to discharge excess of drinking water in the receiving tank to the wastewater pit . The water level of the wastewater pit is kept down below the openings by pumping out the sanitary sewage to the public drain . According to the declaration of the owner of the building, however, the wastewater pump was broken at the time of outbreak . Accidental malfunction of the drainage system caused contamination of drinking water with sanitary sewage through the connecting pipes.

J Appl Bacteriol, 1996 Feb, 80(2), 117 - 23
Variations in R-plasmid DNA concentrations of Escherichia coli during starvation in sewage and brackish waters; Arturo-Schaan M et al.; Cell culturability and plasmid stability in Escherichia coli containing plasmids RP1, R388 and pUB824 were studied in raw and treated wastewater, and in brackish water . The E . coli strain survived well in the three samples of water employed . Moreover, the three plasmids were maintained under all conditions studied . Interestingly, plasmid DNA concentration of individual plasmids followed the same evolution as the culturable bacteria in the corresponding selective medium when the bacteria grew in raw or treated wastewater . In contrast, in brackish water, the stress due to the oligotrophic and salinity conditions of the medium produced an initial paradoxical increase in plasmid DNA concentration, followed by a decrease in the number of culturable bacteria in the corresponding selective medium . Maintenance of RP1 (56 kbp) and R388 (33 kbp) was markedly influenced by nutritive conditions, which caused a segregation of the plasmids from cells . The results of the present study suggest that variations in plasmid DNA concentrations in an aquatic environment depend on the quality of the water and also on the molecular weight of the plasmid considered.

Crit Rev Biotechnol, 1996, 16(1), 53 - 94
Biotechnological developments in Turkey; Ozcengiz G; Turkey is a country not usually associated with industrial biotechnology . However, when current research potential in universities and other R & D centers and particularly contributions made to the international literature since the mid-1980s are taken into account, high-quality international-level work is now commonplace, especially in areas such as industrial microbiology, enzyme technology, biomaterials and biological wastewater treatment . Work in plant biotechnology is at a relatively early stage, but is expected to become a rapidly developing force in the near future . The present article documents current potential in Turkey, based on significant publications produced during the last 8 years.

Med Trop (Mars), 1996, 56(1), 41 - 7
{Survival of Bulinus truncatus and Biomphalaria pfeifferi in sewer water purified in stabilization ponds in a sudanese-saharan zone}; Klutse A et al.; In subsaharan Africa wastewater purification to protect the health of the population could create stagnate water reservoirs for parasitic vectors such as snails which are intermediate hosts of bilharzia . Laboratory studies of the survival of Bulinus truncatus, an intermediate host of Schistosoma haematobium, and Biomphalaria pfeifferi, an intermediate host of Schistosoma mansoni, in waste water purified in stabilization ponds showed that Biomphalaria pfeifferi thrives to dirty water (60 mg/l < or = COD < or = 1060 mg/l) while Bulinus truncatus survived only in slightly cleaner water (60 mg/l < or = COD < or = 200 mg/l) . Field studies showed that Biomphalaria pfeifferi disappeared after 48 hours as compared to 25 days in the laboratory . In both laboratory and field studies Bulinus truncatus survived only 24 hours in raw waste water . The duration of survival grew longer as quality of the water improved . Temperature variations, high amounts of organic material in water, high oxygen content in water, and absence of plant-life are factors which could limit the development of the intermediate snail hosts (i.e . Bulinus truncatus and Biomphalaria pfeifferi) in the waste stabilization ponds of the Interstate School of Rural Equipment Engineers in Ouagadougou, Burkina Faso.

Antonie Van Leeuwenhoek, 1996 Jan, 69(1), 47 - 59
Post-treatments of anaerobic effluents; Tilche A et al.; Post-treatments are necessary if anaerobic effluents need to be discharged into surface waters, because anaerobic digestion alone is not able to produce effluents that can meet the discharge standards applied in most industrialized countries, particularly for suspended solids, particulate COD, nitrogen, phosphorus and sulphides . This paper has the aim to present some results obtained in the recent years in our laboratory, where different comprehensive processes that include anaerobic digestion have been studied . Discussion will regard: 1) the ANANOX (ANaerobic-ANoxic-OXic) process for the treatment of municipal wastewater; 2) a process studied for the biological removal of C, N and P from piggery wastewater that has a hybrid anaerobic/anoxic reactor as the first treatment step; 3) the use of a Sequencing Batch Reactor for the post-treatment of digested cheese whey mixed with cheese factory cleaning waters.

Parassitologia, 1995 Dec, 37(2-3), 229 - 32
Viability of Ascaris suum, Ascaris lumbricoides and Trichuris muris eggs to alkaline pH and different temperatures; Ghiglietti R et al.; Disposal of wastewater sludges in agricultural soil is a way to recover mineral and organic substances . Nevertheless disposing and handling such untreated, potentially contaminated sludges may be hazardous for human health and the environment . The aim of this study is to evaluate a method for sludge decontamination consisting in alkaline treatment with ammonia at different temperatures (22 degrees C, 30 degrees C, 40 degrees C) to establish its effects on the survival of Ascaris suum, Ascaris lumbricoides and Trichuris muris eggs . Our experiments show that the combination of alkalinization with NH4OH at a temperature of 30 degrees C causes the eggs to be inactivated . A 40 degrees C temperature was unfavourable to the development of these helminths in the eggs, with or without addition of NH4OH . At 22 degrees C ammonia did not have any effect on their viability . Ammonia at suitable temperatures therefore, is able to destroy Ascaris and Trichuris eggs . It is suggested that this technology be adopted to decontaminate wastewater sludge before using it as manure in agriculture.

Antonie Van Leeuwenhoek, 1995 Nov, 68(4), 329 - 37
Different types of sludge granules in UASB reactors treating acidified wastewaters; Thaveesri J et al.; The influence of a high energy substrate, i.e . sucrose, on the granular sludge yield and the development of different types of granular sludge was investigated by using Upflow Anaerobic Sludge Bed (UASB) reactors fed with synthetic wastewater . The feed COD was a mixture of volatile fatty acids (VFA) i.e., 20, 40, and 40% of the COD as C2-, C3-, and C4-VFA, respectively . Furthermore, experiments were carried out in which 10 and 30% of the VFA COD was substituted with sucrose . The following distinctly different types of granules were observed in each testrun: in the reactor fed with solely VFA, black (B) and white (W) granules developed; in the reactor fed with a mixture of 90% VFA and 10% sucrose, three types of granules i.e., B, W, and grey (G) granules could be seen; in the reactor fed with 70% VFA and 30% sucrose, only W and G granules were found . The granular sludge yield increased proportional to the amount of sucrose COD . At steady-state performance of the reactors, specific acidogenic (SAA) and methanogenic (SMA) activity tests on these granules revealed that B granules had the highest SMA with low SAA . The W granules had very high SMA with low SAA . G granules gave the highest SAA with a considerable SMA . Measurement of coenzyme F420 revealed that B granules consist mainly of acetoclastic methanogens . The fore-mentioned tests were supplemented with analyses of the wash-out cells present in the reactor effluent and the results suggested that acidogens, if present, prevail at the granule surface . The B granules were particularly rich in Ca, Mn, and Zn minerals . The size distribution analysis showed that the granule diameter increased in the following order: B < W < G granules . The biogas bubbles tended to adhere to the B and W granules but not so strongly to the G granules.

Ecotoxicol Environ Saf, 1995 Nov, 32(2), 139 - 46
Toxicity evaluations of wastewaters in Austria with conventional and cost-effective bioassays; Muna L et al.; The acute toxicity of 42 samples of different types of domestic and industrial discharges was assessed with a battery of tests comprising the standard Daphnia magna bioassay and three cost-effective new microbiotests (cyst-based Toxkits): the Rotoxkit F with the freshwater rotifer Brachionus calyciflorus and the Streptoxkit F and Thamnotoxkit F tests with the freshwater fairy shrimps Streptocephalus proboscideus and Thamnocephalus platyurus, respectively . Chemical analyses were performed for conventional water quality parameters such as chemical oxygen demand (COD), biological oxygen demand (BOD5), NO2, NH3, NH4+, O2, and pH . Toxicity of the samples, expressed as German regulatory G-values, was found to vary between 1 and 128 . The results of these toxicity tests indicate that the Toxkit bioassays were as sensitive as the D . magna acute test . The crustacean T . platyurus was in 75% of the toxic samples more sensitive than D . magna . Relationships between the chemical composition and the toxicity of the discharges could be established in some cases, but not in others, which confirms the difficulties of extrapolating toxic hazards of complex wastes from (mostly restricted) chemical analyses . This study demonstrates the potential of cost-effective bioassays (such as, e.g., cyst-based Toxkits) as attractive alternatives to (expensive) conventional bioassays for routine monitoring of effluents and wastes.

Appl Environ Microbiol, 1995 Nov, 61(11), 3849 - 55
Development of a PCR protocol for sensitive detection of Cryptosporidium oocysts in water samples; Johnson DW et al.; The development of a reliable method of using PCR for detection of Cryptosporidium oocysts in environmental samples with oligonucleotide primers which amplify a portion of the sequence encoding the small (18S) subunit of rRNA producing a 435-bp product was demonstrated . The PCR assay was found to provide highly genus-specific detection of Cryptosporidium spp . after release of nucleic acids from oocysts by a simple freeze-thaw procedure . The assay routinely detected 1 to 10 oocysts in purified oocyst preparations, as shown by direct microscopic counts and by an immunofluorescence assay . The sensitivity of the PCR assay in some seeded environmental water samples was up to 1,000-fold lower . However, this interference was eliminated by either flow cytometry or magnetic-antibody capture . Sensitivity was also improved 10- to 1,000-fold by probing of the PCR product on dot blots with an oligonucleotide probe detected by chemiluminescence . Confirmation of the presence of Cryptosporidium oocysts in water samples from the outbreak in Milwaukee, Wis., was obtained with this technique, and PCR was found to be as sensitive as immunofluorescence for detection of oocysts in wastewater concentrates.

Lett Appl Microbiol, 1995 Nov, 21(5), 307 - 12
Aerobic degradation and dechlorination of 2-chlorophenol, 3-chlorophenol and 4-chlorophenol by a Pseudomonas pickettii strain; Fava F et al.; A Gram-negative aerobic bacterium capable of using 2-chlorophenol (2-CP), 3-chlorophenol (3-CP) and 4-chlorophenol (4-CP) as sole carbon sources was isolated and characterized . The bacterium, designated LD1, was identified to be a Pseudomonas pickettii strain . LD1 was able to totally degrade and dechlorinate 2-CP (initial concentration: 1.51 mmol l-1), 3-CP (initial concentration: 0.57 mmol l-1) and 4-CP (initial concentration: 0.75 mmol l-1) within 30, 30 and 40 h of incubation, respectively, under growing-cell batch conditions . LD1 was also found to be able to metabolize chlorocatechols in growing- and resting-cell conditions . This suggests that the bacterium degrades monochlorophenols through a chlorocatechol pathway . In addition, LD1 was found to be capable of readily metabolizing other organic compounds such as phenol, benzoic acid, hydroxybenzoic acids and hydroquinone . Because of the broad spectrum of monochlorophenols and organic compounds that LD1 can degrade, this bacterium appears to have the potential for being successfully used in the biotreatment of wastewaters and in soil decontamination.

Rev Latinoam Microbiol, 1995 Oct-Dec, 37(4), 325 - 35
{Comparison of ciliate diversity in biodisc reactors which purify industrial wastewater}; Luna-Pabello VM et al.; The comparative study of the ciliate populations present in rotating biological reactors (biodiscs reactors) of 20 l working volume, treating three different wastewaters is the aim of this project . Wastewaters chosen were those of a maize mill, of a sugarcane/ethyl alcohol plant, and of a recycled paper mill . Its dissolved organic contents, measured as soluble chemical oxygen demand (COD) and five-day biochemical oxygen demand (BOD5), were 2040 mg COD/l and 585 mg BOD5/l for maize mill effluents (nejayote), 2000 mg COD/l and 640 mg BOD5/l for sugarcane/ethanol effluents (vinasses), and 960 mg COD/l and 120 mg BOD5/l for whitewaters of the paper industry . Results obtained indicate that ciliate proliferate in all chambers of reactors treating these wastewaters . The ciliates were more abundant in vinasses, followed by nejayote, and then whitewaters . Among protozoa, ciliates were present as follows: 19 species in total . Three of them were common for the three systems . Free swimming ciliates were in higher proportion than pedunculated ones . Its diversity was higher for the whitewaters system, next for nejayote, and the lesser, for vinasses, corroborating the fact that less polluted waters have higher organisms' diversity.

J Environ Sci Health B, 1995 Sep, 30(5), 733 - 58
Nitrogen and phosphorus removal for swine wastewater by ammonium crystallization and intermittent aeration process; Liao CM et al.; A process on crystallized precipitation of ammonium by adding magnesium salt and phosphate was carried out to improve C/N ratio in swine wastewater . After completion of crystallized precipitation of ammonium, an intermittent aeration process with aeration and nonaeration periods alternated at interval of 1:1 hr day-1 is used for the improved swine wastewater (T-N/BOD = 0.14: BOD = 8200 mg/liter and T-N = 1166 mg/liter) . The results obtained from the experiment show that the removal ratios of T-N and NH4-N are 91% and 99%, respectively . T-P is not removed, while the removal ratio of PO4-P is 60% as 3% of CaCl2 liquid is added . The results also indicate that dilution with water is effective to improve the removal of phosphorus even if raw swine wastewater contains high concentrations of T-N, T-P, BOD, and TOC.

J Environ Sci Health B, 1995 Sep, 30(5), 585 - 604
Organophosphate insecticide degradation by non-amended and cupric ion-amended Fenton's reagent in aqueous solution; Dowling KC et al.; Improper treatment and disposal of pesticide-contaminated wastewaters raise concerns for soil and water contamination . Based on the pilot studies described here, chemical treatment via Fenton's reagent (ferrous ion plus hydrogen peroxide) of three organophosphorus insecticides in aqueous solution appears promising . Results show that the Fenton dark reaction degrades methyl parathion, malathion, and methamidophos, and in many cases their breakdown products as well . Addition of cupric ion greatly accelerates insecticide disappearance . To maximize degradation, further studies of the influence of 1) pesticide structure, 2) reagent ratios, and 3) breakdown product competition on reaction rates are necessary.

Arch Microbiol, 1995 Aug, 164(2), 119 - 24
Desulforhabdus amnigenus gen . nov . sp . nov., a sulfate reducer isolated from anaerobic granular sludge; Oude Elferink SJ et al.; From granular sludge of an upflow anaerobic sludge bed (UASB) reactor treating paper-mill wastewater, a sulfate-reducing bacterium (strain ASRB1) was isolated with acetate as sole carbon and energy source . The bacterium was rod-shaped, (1.4-1.9 x 2.5-3.4 microns), nonmotile, and gram-negative . Optimum growth with acetate occurred around 37 degrees C in freshwater medium (doubling time: 3.5-5.0 days) . The bacterium grew on a range of organic acids, such as acetate, propionate, and butyrate, and on alcohols, and grew autotrophically with H2, CO2, and sulfate . Fastest growth occurred with formate, propionate, and ethanol (doubling time: approx . 1.5 days) . Strain ASRB1 clusters with the delta subdivision of Proteobacteria and is closely related to Syntrophobacter wolinii, a syntrophic propionate oxidizer . Strain ASRB1 was characterized as a new genus and species: Desulforhabdus amnigenus.

Ecotoxicol Environ Saf, 1995 Aug, 31(3), 205 - 10
Microalgae and wastewater treatment; Hammouda O et al.; The performance of microalgae aquaculture wastewater treatment system predominated mainly by Scenedesmus and Chlorella was assessed . Treatment induced a progressive reduction in both COD and BOD to values below the discharge limits . Different patterns were obtained for removal of phosphorus, nitrogen, and ammonia; however, the algal culture efficiencies reached 100% in their removal by the end of the treatment period . The applied aquatic systems demonstrated percentage reduction of heavy metals in the range between 52.3 and 100% in the batch system and 64.2 and 100% in the continuous system . Wastewater supported algal growth by inducing the incorporation of a significantly higher content of the individual amino acids Asp, Thr, Ser, Glu, Gly, and Tyr, and a markedly higher level of Pro . However, His, Lys, and Arg were markedly reduced compared to their levels in synthetic-medium-grown algae.

Dtsch Tierarztl Wochenschr, 1995 Jul, 102(7), 278 - 83
{Effect of structural changes in animal husbandry on the environment due to wastes and residues from animal production}; Bohm R; From the statistic data it can be taken, that especially in the old federal states of Germany, in the new future animal husbandry will be more and more concentrated in certain regions . This structural change probably is followed by a similar concentration process concerning slaughterhouses and within limitations the rendering industry too . This will result in a higher regional environmental pollution by volatile and soluble components as well as microorganism from agricultural wastes of animal origin, by offal and by products from slaughtering as well as by highly contaminated slaughterhouse wastewater and by pollutants in air and waste-water from rendering plants . Further regional environmental and epidemiological risks are connected with recycling of voluminous slaughterhouse wastes like rumen-, stomach- and gut-contents to the farms as fertilizers, unless strictly hygienic guidelines have to be followed in the future.

Biodegradation, 1995 Jun, 6(2), 93 - 107
The development of a novel strategy for the microbial treatment of acrylonitrile effluents; Wyatt JM et al.; Effluent from the manufacture of acrylonitrile is difficult to biodegrade . It contains nine major organic components: acetic acid, acrylonitrile, acrylamide, acrylic acid, acrolein, cyanopyridine, fumaronitrile, succinonitrile, and maleimide . A range of bacteria have been isolated that can grow on, or convert all of the organic components of effluent from the manufacture of acrylonitrile . These bacteria can be used as the basis of a mixed culture system to treat the effluent . The bacteria were utilised in batch and continuous cultures to degrade a synthetic wastewater containing acrylonitrile, acrylamide, acrylic acid, cyanopyridine and succinonitrile . The mixed microbial population was adapted by varying the growth rate and switching from continuous to batch and back to continuous growth, to degrade these five compounds as well as acrolein, fumaronitrile and maleimide.

Vaccine, 1995 Jun, 13(9), 835 - 40
Antigenicity of hepatitis A virus after ultra-violet inactivation; Wang CH et al.; Ultra-violet (UV) treatment has been shown to inactivate hepatitis A virus (HAV) in wastewater and polluted drinking water . Whether this method could be used to inactivate virus preparations made for vaccine purposes is not known since the effect of UV on the antigenicity of HAV has not been studied . HAV vaccine preparations have been treated effectively with formaldehyde . However, this method is time-consuming, since treatment times of up to 15 days have been published as necessary for a complete and safe inactivation . We used a cell-culture-derived HAV preparation with a TCID50 of 10(9) for a UV irradiation experiment . The antigenicity (assessed by a panel of anti-HAV antibodies), viral genome titre (quantitated by polymerase chain reaction) and HAV infectivity were compared after treatment with UV doses of 0, 184, 368, 552, 736 and 920 J m-2 . Our results showed the antigenicity of HAV was almost unaltered even when infectious viral particles were no longer detectable . This technique shows potential as a simple and low-cost method for an inactivated HAV vaccine.

Biol Rev Camb Philos Soc, 1995 May, 70(2), 243 - 75
Treatability, toxicity and biodegradability test methods; Kilroy A et al.; 1 . This review confirms that treatability and biodegradability test methods have been cited extensively in the literature . It is clear that the method selected depends on the specific objectives of the test, i.e . the determination of whether a substance is toxic, biodegradable or treatable . Factors that have to be considered when selecting the test methods are the cost of performing the test, the time and resources involved, and the accuracy required . It often appears that more extensive simulation studies are required after initial screening tests have been performed . 2 . Many of the enzyme and bacterial growth tests which have been developed for monitoring or screening of toxicants and their persistence in water and wastewaters have been reviewed . Most of these tests are rapid, inexpensive, and reproducible . Most of the biochemical and microcalorimetric approaches, although promising, are still in their infancy as regards toxicity testing . Therefore, biological testing still appears to be most suitable for routine assessment . 3 . Micro-organisms are particularly suitable for use in toxicity testing of chemicals as they are inexpensive to culture, have rapid growth rates, and usually provide reproducible results (Vaishnav & Korthals, 1990) . Many bioassays have been developed to evaluate the toxicity and treatability of municipal and industrial effluents . Numerous single species tests have been recommended by several authors (Dutka et al., 1983; Beaubien et al . 1986) . Such approaches are mainly based on the belief that, by selecting the most sensitive species and by using appropriate factors to allow for variability not included in the test, the highest levels of biological organization will be adequately protected . Single species tests are now quite well established, and when properly used, are easy to analyse and quantify . However, it has been pointed out (Levin, 1984) that the results obtained from single species tests cannot easily be applied to natural field conditions because the test organisms are extensively laboratory acclimated; also the test conditions provide for optimized growth and survival, a situation unlikely to be found in the field . Moreover, a fundamental problem with this approach is that it assumes that the ecosystem is a collection of single species exposed to toxicants under constant conditions (Cairns, 1982) . Multi-species toxicity tests, that is the use of mixed cultures or communities of micro-organisms for a testing protocol, are found to be generally much less sensitive than single species tests (Dutka & Kwan, 1984).(ABSTRACT TRUNCATED AT 400 WORDS)

Appl Environ Microbiol, 1995 Apr, 61(4), 1246 - 51
Anaerobic oxidation of ammonium is a biologically mediated process; van de Graaf AA et al.; A newly discovered process by which ammonium is converted to dinitrogen gas under anaerobic conditions (the Anammox process) has now been examined in detail . In order to confirm the biological nature of this process, anaerobic batch culture experiments were used . All of the ammonium provided in the medium was oxidized within 9 days . In control experiments with autoclaved or raw wastewater, without added sludge or with added sterilized (either autoclaved or gamma irradiated) sludge, no changes in the ammonium and nitrate concentrations were observed . Chemical reactions could therefore not be responsible for the ammonium conversion . The addition of chloramphenicol, ampicillin, 2,4-dinitrophenol, carbonyl cyanide m-chlorophenyl-hydrazone (CCCP), and mercuric chloride (HgIICl2) completely inhibited the activity of the ammonium-oxidizing sludge . Furthermore, the rate of ammonium oxidation was proportional to the initial amount of sludge used . It was therefore concluded that anaerobic ammonium oxidation was a microbiological process . As the experiments were carried out in an oxygen-free atmosphere, the conversion of ammonium to dinitrogen gas did not even require a trace of O2 . That the end product of the reaction was nitrogen gas has been confirmed by using 15NH4+ and 14NO3- . The dominant product was 14-15N2 . Only 1.7% of the total labelled nitrogen gas produced was 15-15N2 . It is therefore proposed that the N2 produced by the Anammox process is formed from equimolar amounts of NH4+ and NO3-.

Mutat Res, 1995 Mar, 342(1-2), 1 - 8
Mutagenicity and toxicity of water extracts from the Sora river area; Filipic M; The present study was conducted on the waters of the Sora river and effluents entering to the river . The samples were extracted with XAD-2 resin at different pH and tested for mutagenicity with the modified Ames test using strains S . typhimurium TA98 and TA100 . The majority of the mutagenic activity of the samples was found in the neutral pH fraction of the extracts . Strain TA98 in the presence of metabolic activation was the most sensitive condition of mutagenicity . Of the eleven sample extracts, six were positive; neutral fractions of the effluent from wastewater treatment plant, the water leaching from the municipal dump, the water from the lake lying beneath the dump and the untreated effluent, and acid fractions of two samples taken directly from the river . The water leaching from the municipal dump was also mutagenic and toxic without previous extraction . Mutagenic responses before and after extraction of this sample indicate that components responsible for mutagenicity were partly extracted in the neutral fraction . The toxicity of water samples and extracts was tested with Microtox assay, and acid fractions of the extracts were more toxic than the neutral fractions . Comparing the toxicity to the mutagenicity data indicates that components responsible for toxic and mutagenic response were at least partly separated between acid and neutral fraction respectively.

Curr Microbiol, 1995 Mar, 30(3), 155 - 60
Conjugal transfer of natural plasmids between Escherichia coli strains in sterile environmental water; Tamanai-Shacoori Z et al.; Seven antibiotic-multiresistant Escherichia coli strains, possessing three or four plasmids, capable of transferring their resistance marker at a high frequency, were selected among a total of 300 antibiotic-resistant E . coli strains isolated from natural water--raw and treated wastewater, and brackish water (collected 1 km downstream) . These strains were mated with E . coli K-12 C600 nalr, both in sterilized natural water and LB medium at 25 degrees C . Conjugation did occur in all the systems tested, although fewer transconjugants were recovered from raw and treated wastewater experiments . In contrast, in brackish and seawater, the transfer frequency did not significantly decrease in spite of salt contents . In 100% of the cases, transfer of the high-molecular-weight plasmids (> or = 20 kb) was observed, but the small plasmids (2.6-7.5 kb) were only cotransferred in raw or treated wastewater and in brackish water . Moreover, genotypic variation occurred more frequently in natural water than in LB medium.

Appl Environ Microbiol, 1995 Jan, 61(1), 13 - 20
Development and application of a monoclonal antibody against Thiothrix spp; Brigmon RL et al.; Historically, methods used to identify Thiothrix spp . in environmental samples have been inadequate because isolation and identification procedures are time-consuming and often fail to separate Thiothrix spp . from other filamentous microorganisms . We described a monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) procedure which was used to identify Thiothrix spp . in wastewater, artesian springs, groundwater, and underwater subterranean samples . The ELISA utilized monoclonal antibody T3511 to a species-specific carbohydrate epitope of Thiothrix spp . No cross-reactions were observed among non-Thiothrix strains consisting of 12 species and nine genera . In field trials, the ELISA identified 100% of 20 biochemically and cytologically confirmed Thiothrix spp.-containing samples with no false positives . Indirect immunofluorescent microscopy utilizing T3511 was effective for wastewater samples but not for those from natural spring water because of background fluorescence in the latter . In addition, electron micrographs of Thiothrix spp . labeled with T3511-biotin-anti-mouse antibody-gold showed that epitope T3511 was intracellular both in laboratory strains and environmental isolates . The minimum level of detection of the ELISA was 0.10 microgram/ml.

Antonie Van Leeuwenhoek, 1995, 67(1), 103 - 10
The physical characteristics of anaerobic granular sludges in relation to their internal architecture; Forster CF et al.; A range of granular sludges was taken from industrial anaerobic sludge blanket reactors treating a wide variety of wastewaters and a comparison was made between the polymers which were extractable from the granules and their internal structures . The study of the internal structure, using sequential staining of ultra-thin sections, showed the complexity of granular sludges . Much of the area was occupied by Gram-negative cells and the area which stained positive for protein was found to increase nearer the centre of the granules . This was accompanied by a decrease in the carbohydrate positive areas . Positive areas for lipid were widespread throughout the granules . Changes in the internal structure were observed when the type of wastewater treated by the granules was changed and a comparison between sludges treating the same type of wastewater showed that factors other than the nature of the substrate must be considered as parameters which will affect the structure of the granules . Although an appreciable variation in the granule strengths was noted, it was not possible to relate these differences, on an overall basis, to either the internal structure or the chemical composition of the extracted polymers . However, an examination of data for granules produced during the treatment of nominally similar wastes did suggest that there would be a relationship between polymer composition and granule strength in these cases.

Food Chem Toxicol, 1994 Nov, 32(11), 1021 - 30
Denver Potable Water Reuse Demonstration Project: comprehensive chronic rat study; Condie LW et al.; The health effects testing program for the Denver Water Department's Potable Water Reuse Demonstration Project was designed to evaluate the relative health effects of highly treated reclaimed water derived from secondary wastewater in comparison with Denver's present high-quality drinking water . The 1 x 10(6) gal/day treatment plant provided 500-fold concentrates of water that had been treated by multiple processes to remove microbial and chemical contaminants . Fischer 344 rats were exposed to the complex mixture solutions for up to 2 yr to evaluate chronic toxicity and oncogenicity effects . The following parameters were evaluated: clinical observations, survival rate, growth, food and water consumption, haematology, clinical chemistry, urinalysis, organ weights, gross autopsy and histopathological examination of all lesions, major tissues and organs . Clinical pathology, gross pathology, and microscopic pathology conducted at wk 26 and 65 and at the end of the study did not reveal any findings that could be considered to be treatment related . Administration of drinking water concentrates at up to 500 times the original concentration in the original water samples to F344 rats for up to 104 wk did not result in any overt toxicological or carcinogenic effects.

J Chem Technol Biotechnol, 1994 Oct, 61(2), 179 - 82
Enzymatic removal of selected aromatic contaminants from wastewater by a fungal peroxidase from Coprinus macrorhizus in batch reactors; al-Kassim L et al.; The use of enzymes such as horseradish peroxidase (HRP) for degrading or removing toxic organics from synthetic wastewater has been demonstrated previously . Potential alternatives to HRP are other peroxidases, various ligninases, haloperoxidases and laccases . Results of this study indicate that a fungal peroxidase from Coprinus macrorhizus (CMP) has the capability to catalyze the same reactions as HRP . Similarly, in batch reactors the trend and removal efficiency of aromatic compounds by CMP from synthetic wastewater depend on the nature of the compound.

J AOAC Int, 1994 Sep-Oct, 77(5), 1253 - 63
Determination of inorganic anions in water by ion chromatography: a collaborative study; Edgell KW et al.; The U.S . Environmental Protection Agency (U.S . EPA) and the American Society for Testing and Materials (ASTM) conducted a joint collaborative study validating an ion chromatographic method for determination fo inorganic anions (U.S . EPA method 300.0A and the equivalent proposed revision to ASTM method D4327) . This study was conducted to determine the mean recovery and precision of analyses for bromide, chloride, fluoride, nitrate, nitrite, orthophosphate, and sulfate in reagent water, drinking water, and wastewater . The study design was based on Youden's nonreplicate plan for collaborative tests of analytical methods . The test waters were spiked with the anions at 6 concentration levels, prepared as 3 Youden pairs . The 22 volunteer laboratories were instructed to dilute 10 mL sample concentrate to 100 mL test water . A measured volume of sample (20-200 microL) was injected into an ion chromatograph equipped with a guard column, anion exchange column, and a chemical micromembrane suppression device . The anions were then separated using 1.7 mM sodium bicarbonate and 1.8 mM sodium carbonate, and measured by a conductivity detector . Submitted data were evaluated using U.S . EPA's IMVS computer program, which follows ASTM D2777-86 statistical guidance . U.S . EPA method 300.0A and ASTM method D4327 were judged acceptable for measurement of the above anions (except sulfate) at concentrations ranging from 0.3 to 25 mg/L and sulfate concentrations from 2.9 to 95 mg/L . Mean recoveries for the 7 anions from all matrixes, as estimated from the linear regression equations, ranged from 95 to 104% . At concentrations above 2-6 mg/L for bromide, fluoride, nitrate, nitrite, and orthophosphate, and above 24 mg/L for sulfate, the overall and single-analyst relative standard deviations were less than 10 and 6%, respectively . As concentrations decreased, precision became more variable . The relative standard deviations of results for chloride were slightly higher than the other anions, especially in matrixes with high chloride background . Analysis of Variance (ANOVA) tests at the 95% confidence interval indicated a statistically significant matrix effect for chloride, nitrite, and nitrate analyses in drinking water compared to analyses in reagent water . Because these matrix effects were caused by the spiking process and not the drinking water itself, the ANOVA determination was not considered to be of practical significance.

Australas Biotechnol, 1994 Sep-Oct, 4(5), 292 - 7
Biological sorption and uptake of toxic metal ion from wastewaters; Madgwick JC; Microorganisms and algae have potential as agents for removing inorganic pollutants from wastewaters . Metal ion uptake mechanisms function either by passive chemical adsorption or by metabolically driven processes . Ion selective uptake processes are being sought in algae to facilitate purification of valuable metal ions for recycling . Sessile macroalgae growing in seawater are useful bioindicators for detecting metal ion contamination in the marine environment.

Appl Environ Microbiol, 1994 Aug, 60(8), 2963 - 70
Detection of adenoviruses and enteroviruses in polluted waters by nested PCR amplification; Puig M et al.; A procedure has been developed for the rapid detection of enteroviruses and adenoviruses in environmental samples . Several systems for virus concentration and extraction of nucleic acid were tested by adding adenovirus type 2 and poliovirus type 1 to different sewage samples . The most promising method for virus recovery involved the concentration of viruses by centrifugation and elution of the virus pellets by treatment with 0.25 N glycine buffer, pH 9.5 . Nucleic acid extraction by adsorption of RNA and DNA to silica particles was the most efficient . One aliquot of the extracted nucleic acids was used for a nested two-step PCR, with specific primers for all adenoviruses; and another aliquot was used to synthesize cDNA for a nested two-step PCR with specific primers for further detection of seeded polioviruses or all enteroviruses in the river water and sewage samples . The specificity and sensitivity were evaluated, and 24 different enterovirus strains and the 47 human adenovirus serotypes were recognized by the primers used . The sensitivity was estimated to be between 1 and 10 virus particles for each of the species tested . Twenty-five samples of sewage and polluted river water were analyzed and showed a much higher number of positive isolates by nested PCR than by tissue culture analysis . The PCR-based detection of enteroviruses and adenoviruses shows good results as an indicator of possible viral contamination in environmental wastewater.

Arch Environ Contam Toxicol, 1994 Jul, 27(1), 25 - 8
Evaluation of a microplate assay specific for heavy metal toxicity; Bitton G et al.; A rapid, quantitative microbial assay, which is specific for heavy metal toxicity, has been developed . The assay (MetPLATE) is in a 96-well microtitration plate format and is suitable for determining toxicity characteristics such as median inhibitory concentrations . The sensitivity of MetPLATE to heavy metals {Cu, Zn, Cd, Pb, Hg, Cr(III)} was generally higher than Microtox and was of the same order as or better than Daphnia and fish bioassay . MetPLATE was insensitive to organic compounds at concentrations higher than those found in the environment . Six out of 10 industrial wastewaters or process waters surveyed were toxic . Heavy metal analysis of these waters confirmed the presence of heavy metals in the toxic samples . MetPLATE can be run concurrently with other assays for general toxicity to help determine the nature of chemicals causing toxicity.

J Dairy Sci, 1994 Jul, 77(7), 2008 - 30
Components of dairy manure management systems; Van Horn HH et al.; Dairy manure management systems should account for the fate of excreted nutrients that may be of environmental concern . Currently, regulatory oversight is directed primarily at the assurance of water quality; N is the most monitored element . Land application of manure at acceptable fertilizer levels to crops produced on the farm by hauling or by pumping flushed manure effluent through irrigation systems is the basis of most systems . Nutrient losses to surface and groundwaters can be avoided, and significant economic value can be obtained from manure as fertilizer if adequate crop production is possible . Dairies with insufficient crop production potential need affordable systems to concentrate manure nutrients, thereby reducing hauling costs and possibly producing a salable product . Precipitation of additional nutrients from flushed manures with sedimented solids may be possible . Composting of separated manure solids offers a possible method to stabilize solids for distribution, but, most often, solids separated from dairy manures are fibrous and low in fertility . Manure solids combined with wastes from other sources may have potential if a marketable product can be produced or if sufficient subsidy is received for processing supplementary wastes . Solutions to odor problems are needed . Energy generated from manure organic matter, via anaerobic digestion, reduces atmospheric emissions of methane and odorous compounds . Use of constructed wetlands or harvesting of photosynthetic biomass from wastewater has the potential to improve water quality, making extensive recycling possible.

Microbiol Res, 1994 Jun, 149(2), 105 - 14
Alteration of viral infectious behavior by surface active agents; Vanden Bossche G; Phosphate buffered saline (PBS) and wastewater retentate, which had been adjusted to the same level of pH and ionic strength by addition of a concentrated PBS solution, were experimentally seeded with polio- or parvovirus and treated with various concentrations of sodium dodecylsulfate (SDS) and dodecyltrimethylammoniumbromid (DTAB), respectively . Upon subsequent assessment for viral infectivity of the samples in Buffalo green monkey kidney cell cultures, infectivity modulating effects of DTAB in PBS and of SDS in retentate appeared to be largely affected by the electrical charge of the suspended virions . However, if PBS or retentate samples were treated with SDS or DTAB respectively, different isoelectric properties between polio- and parvovirus particles were less likely to affect the detergent concentration required for optimal virus recovery . Moreover, in the presence of soluble organics, optimal virus recovery rates were obtained with much lower detergent concentrations if the samples had been treated with DTAB instead of SDS . Measurement of the effective critical micelle concentration as well as multiangle electrophoretic light scattering (MELS) seemed to provide a simple approach to monitoring colloidal stability of multicomponent viral particle (VP) suspensions upon the addition of ionic detergents . By measuring zeta potential distribution, MELS offers additional information about alterations to electrical viral surface properties . Since the behavior of VPs is well known to largely depend upon their electrical characteristics within the environment in which they exist, there is substantial evidence that MELS can provide valuable guidelines in studying optimal detergent-treatment conditions for virus recovery from aqueous suspensions.

J Chem Technol Biotechnol, 1994 Jun, 60(2), 171 - 6
Effects of the seed sludge on the performance of UASB reactors for treatment of toxic wastewater; Peng D et al.; A comparative study of different sludges (anaerobic sewage sludge and anaerobic sewage sludge cultivated for 30 days) as the seed of UASB reactors for treatment of synthetic resin production wastewater was carried out on a laboratory scale . Significant differences in reactor performance were observed . With anaerobic sewage sludge seed, the reactor obtained a 71% COD removal efficiency and produced 2.94 dm3 biogas per dm3 wastewater under an organic loading rate of 4.5 kg COD m-3 day-1 . The sludge in the reactor was diffuse and possessed poor settling ability, which led to effluent SS as high as 1200 mg dm-3 . However, with anaerobic sewage sludge cultivated with synthetic substrate for 30 days as a seed, the same reactor gave 78% COD removal efficiency and produced 3.5 dm-3 biogas per dm3 wastewater at the same loading rate . Moreover, the sludge in the reactor was completely granulated and possessed good settling ability, which resulted in effluent SS as low as 200 mg dm-3 . The granular sludge produced less biomass per gram COD removed than the diffused sludge . Anaerobic sewage sludge cultivated for a short time could form the nuclei of granules for the reactor, allowing granulation to proceed smoothly . Therefore, sludge nuclei are a prerequisite of sludge granulation in UASB reactors for treatment of toxic wastewater.

Ecotoxicol Environ Saf, 1994 Jun, 28(1), 25 - 34
Occurrence of toxic metabolites from nonionic surfactants in the Krka River estuary; Kvestak R et al.; The occurrence and behavior of nonylphenol (NP), nonylphenol monoethoxylate (NP1EO), and nonylphenol diethoxylate (NP2EO) were studied in the Krka River estuary . Quantitative determinations using normal-phase high-performance liquid chromatography with spectrofluorimetric detection were performed in both municipal wastewaters and receiving estuarine waters . The concentrations of NP, NP1EO, and NP2EO in municipal wastewaters varied within the ranges of < 0.5-419, < 0.5-35, and < 0.5-54 micrograms/liter, respectively; thus, in general representing only a minor fraction of the total surfactant-derived nonylphenolic compounds . The concentration decrease after the wastewater discharge into the estuary was very sharp, which was assigned primarily to an efficient dilution of the wastewater plume . Consequently, the concentrations of NP, NP1EO, and NP2EO in the estuary were fairly low, the respective concentration ranges being < 20-1200, < 20-440, and < 20-1300 ng/liter . Rather complicated distribution patterns of NP, NP1EO, and NP2EO were obtained on the vertical profile of the estuarine water column with the concentration maxima at the estuarine phase boundaries, i.e., air-freshwater and freshwater-seawater . Moreover, the ratio between individual nonylphenolic compounds varied significantly, indicating that transformation reactions played a significant role in their distribution and fate in the estuary.

Ann N Y Acad Sci, 1994 May 2, 721, 440 - 9
Bioextraction (reductive dissolution) of iron from low-grade iron ores . Fundamental and applied studies; DiChristina TJ; Results of the present study indicate that S . putrefaciens 200 may be a suitable Fe(3+)-reducing microorganism for commercial application in a microbially catalyzed iron ore bioextraction (reductive dissolution) process . The proposed scheme of the bioextraction process (Fig . 1) entails the addition of a suitable iron ore to anaerobic, batch cultures of aerobically grown S . putrefaciens 200, with subsequent recovery of Fe2+ in the product stream . Although batch growth under low oxygen tension is known to induce expression of the high-rate Fe3+ reduction system in S . putrefaciens, such growth conditions do not appreciably enhance the rate at which S . putrefaciens catalyzes the reductive dissolution of iron from low-grade iron ore . As a result, strict monitoring of dissolved oxygen levels during batch growth is not required . Highly aerobic growth conditions are most desirable because such conditions maximize microbial growth rates . Commercial application of the proposed process is made more attractive by the ability to grow S . putrefaciens aerobically on a relatively inexpensive organic substrate (filter-sterilized, primary effluent wastewater) as sole carbon and energy source . Physical and chemical factors that accelerate overall reductive dissolution rates include (i) pulverization of the iron ores before their addition to the anaerobic, batch cultures, and (ii) subsequent addition of an Fe(III)-chelating agent to the anaerobic iron ore-microorganism slurry . Recycle of residual ore remaining in the initial reactor vessel after a one-hour incubation is recommended, since overall reductive dissolution rates decrease dramatically after that time . Significant enhancement of the overall reductive dissolution rates may reside in the ability to genetically engineer a more robust Fe(3+)-reducing microorganism . Preliminary genetic studies presented here indicate that S . putrefaciens is a suitable model microorganism for studying the molecular basis of microbial Fe3+ reduction . Mutagenesis experiments demonstrated that the Fe3+ reduction system of S . putrefaciens is physiologically uncoupled from other electron-accepting processes carried out by this bacterium, and that a distinct ferrireductase enzyme is expressed after growth under either highly aerobic or microaerobic conditions . An array of S . putrefaciens mutants (Class I), deficient only in their ability to grow anaerobically on Fe3+ as sole terminal electron acceptor, were isolated and a single mutant selected for subsequent gene cloning (complementation) experiments . Restriction enzyme analysis of putative, complemented clones (i.e., transconjugates in which the ability to grow anaerobically on Fe3+ had been restored) revealed the presence of a common cloned DNA insert.(ABSTRACT TRUNCATED AT 400 WORDS)

Ann N Y Acad Sci, 1994 May 2, 721, 399 - 406
Plasmid-mediated degradation of hydroxylated, methoxylated, and carboxylated benzene derivatives in Moraxella sp; Vasudevan N et al.; Chemical industries produce wastewater that contains large amount of aromatic substances including chlorinated compounds . Moraxella sp . isolated from a petroleum refinery unit efficiently used a variety of benzene derivatives bearing hydroxyl, methoxyl, carboxyl, and chloro- groups as the sole carbon source . The isolate harbored two plasmids of high mobility that are responsible for the utilization of these substrates.

Am Ind Hyg Assoc J, 1994 May, 55(5), 438 - 42
Evaluation of chemical releases and worker exposures from filter press operations; Timberlake DL et al.; The exposures (inhalation and dermal) and releases (air, water, solids, and process streams) associated with the filtration of industrial wastewater sludge from an electronics manufacturing plant were characterized . Chemical releases and worker exposures for a target chemical (total copper) were measured over four operational cycles . Various aspects of the filtration operation believed to influence the measurement values were documented . Worker exposures associated with the discreet stages of the filter operation were measured . Ventilation patterns around the filter press were also monitored . The workers' time-weighted average exposures to total copper during the 113-minute operational cycle ranged from 3.1 to 25 micrograms/m3 (2.2 geometric standard deviation, 6.4 micrograms/m3 geometric mean concentration) . The manual removal of filter cake comprised only 15% of the time in an average filtration cycle, but produced 72% of the workers' inhalation exposure . During this cake-removal stage, inhalation exposures ranged from 11 micrograms/m3 to 130 micrograms/m3 (2.5 geometric standard deviation, 30 micrograms/m3 geometric mean concentration) . Differences in worker technique may account for the large range of inhalation exposures during the cake-removal stage . Exposures and releases were successfully determined for a single unit operation, as well as for the discreet stages of operation . The data generated will enable EPA to more accurately estimate worker exposures and chemical releases for new chemicals as required by the Toxic Substances Control Act . The approach utilized will benefit industrial hygienists in providing estimates of worker exposures and aid in the targeting of survey sampling.

Environ Health Perspect, 1994 Mar, 102(3), 310 - 2
Environmental health knowledge and practice survey among secondary schoolchildren in Zaria, Nigeria; Ebong RD; Knowledge of environmental health was assessed in a sample of 192 students at Ja'afaru Secondary School, Zaria, Nigeria, by means of a questionnaire . A follow-up practice survey was also administered to assess the environmental sanitation of the school and the homes of a subsample of the students . Observations were recorded on the sources of water, the methods of refuse and sewage disposal, and the hygienic condition of the toilets in both the school and the homes surveyed . The findings indicated that the students' knowledge of environmental hygiene was high for all classes and that students whose fathers had primary, secondary, or post-secondary education scored slightly higher than those whose fathers were illiterate . Analysis of the observations on environmental sanitation showed that even though the school lacked indoor plumbing on the premises, the pupils were accustomed to pipe-borne and well water in their homes . The main method of refuse disposal for school and homes was open dumping, and the main method of sewage disposal for both school and homes was pit latrines, which were dirty and poorly maintained . Although the pupils had good knowledge of environmental hygiene, inadequate opportunities and lack of sanitation facilities at school and homes did not allow them to practice the health knowledge they had acquired . Recommendations were made to the school authority to direct more effort toward providing a safe and adequate water supply, good drainage systems, additional toilets, and renovating the existing toilets . The school should also emphasize the practice of good environmental hygiene to complement theoretical inputPIP: The objectives of the study, carried out between June and September 1989, were to assess knowledge of environmental hygiene of a stratified random sample of 192 pupils consisting of 101 (52.6%) males and 91 (47.4%) females at the Ja'afaru Secondary School, Zaria, Nigeria, and to assess the available sanitation facilities in the school and homes of a subsample . The information was obtained regarding: 1) personal data: age, sex, present class in school, total years of schooling, and family size; 2) parental education and occupation; and 3) students' knowledge of environmental hygiene . Thirty-seven (19.3%) students were in class three, 84 (43.7%) were in class four, and 71 (37%) were in class five . 28.6% of fathers and 49.0% of mothers were illiterate . 61.5% of parents were skilled workers . With respect to environmental hygiene, students had good knowledge of the subject . Most of them answered the questions correctly . Students with literate fathers scored slightly higher than those with illiterate fathers . Although 39 (20.3%) children whose fathers were illiterate got 100% of the questions correct, 88 (45.8%) children with literate fathers scored 100% . Environmental sanitation of the homes of the subsample of 54 students, made up of 26 males and 28 females, and that of the school was also assessed . 78% of the households surveyed (42) had a functioning pipe-borne water supply; 22% of households (12) obtained water from wells . 89.9% of households practiced open dumping of refuse . 70.1% of households used pit latrines for sewage disposal (and of these only 36% had toilets that were clean), while 20.9% practiced indiscriminate disposal of feces . Only 18 (33%) households had properly constructed drainage systems for wastewater, and 36 (67%) had open drainage systems . Recommendations were made to the school authority to focus more effort on the provision of a safe and adequate water supply, good drainage systems, additional toilets, and renovation of the existing toilets .

Ecotoxicol Environ Saf, 1994 Mar, 27(2), 128 - 57
A field study of environmental impacts at a bleached kraft pulp mill site on the Baltic Sea coast; Landner L et al.; The rate of technical development in bleaching of chemical pulp and the upgrading of process control and wastewater treatment systems in the pulp industry have been extremely rapid over the past few years . When assessing the environmental impacts of bleached kraft pulp mill effluents (BKMEs), it is therefore more important than ever to carefully characterize the bleaching process, the composition of the treated effluent, and the degree of exposure of sensitive target organisms in the receiving water body . These requirements have not always been fulfilled in previous reports on biological effects of BKMEs in Scandinavia . This work presents the results of a comprehensive field study of the impacts of a 350,000-tonne kraft mill, bleaching softwood and hardwood pulp in campaigns according to the sequence O(D25,C70+D5)(EOP)D(EP)D . The effluent is treated in an aerated lagoon with a mean retention time of 8-9 days, practically eliminating chlorate and resin acids, and reducing the discharge of adsorbable organic halogen (AOX) to an average of 1 t/day (1.3 and 0.4 kg/ADt for softwood and hardwood, respectively) . The treated effluent is discharged through a 1.3-km-long diffuser, at a water depth of 9-12 m, into a well ventilated coastal area, giving a 1000-fold dilution within 3-4 km from the diffuser . The actual exposure of the coastal ecosystem to BKME components was determined by analysis of extractable organic chlorine in suspended solids and of conjugates of chlorophenolics in the bile of feral perch . Despite a major damage to the benthic communities that occurred about 10 years ago, and was due to large chlorate discharges at the time, no direct detrimental effects on benthic flora and fauna could be ascribed to the present BKME discharge . Instead, a clear recovery of the Fucus community, although not yet completed, could be demonstrated . Studies of the composition, abundance and biomass of the fish community, the recruitment and survival of fish fry, and the physiological status of perch, using a set of biomarkers, revealed that even in the most BKME-exposed area, only minor effects were detected . These effects were related to eutrophication/enrichment rather than to the action of toxic substances . The general effect picture, thus, was essentially of a different type than the one recorded in previous studies of mills, which used older technology and less effective process and effluent treatment control, and which were discharging into enclosed, shallow bays of the Baltic Sea.

Mutat Res, 1994 Feb, 312(1), 17 - 24
Evaluation of the Allium anaphase-telophase test in relation to genotoxicity screening of industrial wastewater; Rank J et al.; The Allium anaphase-telophase test was evaluated to find out if it could be recommended in the screening of wastewater for genotoxicity . Five mutagenic or carcinogenic chemicals usually found in wastewater were tested in the Allium anaphase-telophase test . Sodium dichromate (25 microM), benzene (100 microM), dichloromethane (175 microM) and 1,1,1-trichloromethane (175 microM) increased the frequency of chromosome aberrations in the root cells, whereas formaldehyde (1 mM) was found to be non-mutagenic in this test system . Other studies where chemicals were tested in the Allium test were reviewed . For 15 chemicals the results were compared with results from the Ames test, the Microscreen assay, and carcinogenicity tests in rodents . The sensitivity of the Allium test was calculated to be 82% . In conclusion the Allium test is recommended for the screening of wastewater because it has a high sensitivity, is cheap, rapid, easy to handle, and because it can be used on wastewater without pretreatment of the sample.

J Occup Med, 1994 Jan, 36(1), 31 - 5
Proportional mortality analysis of wastewater treatment system workers by birthplace with comments on amyotrophic lateral sclerosis; Betemps EJ et al.; There is concern that wastewater treatment system workers are at risk for cancers and diseases affecting the neurological and digestive systems . However, these diseases have also been linked to early exposures . A proportional mortality study was conducted on a large cohort of wastewater treatment system workers who were divided into two groups, migrants and nonmigrants, by place of birth as reported on their death certificates . The migrant worker group was significantly higher than the US white male population for cancer of the stomach, leukemia, and all lymphopoietic cancers . Migrant workers also had an elevated ratio for all diseases of the nervous system and sense organs . No cases of amyotrophic lateral sclerosis were found . The American-born workers had an elevated rate of death for arteriosclerotic heart disease compared with the US white male population . We suggest that place of birth may present a confounding factor when evaluating exposures in employee groups.

Appl Environ Microbiol, 1994 Jan, 60(1), 227 - 34
Importance of cobalt for individual trophic groups in an anaerobic methanol-degrading consortium; Florencio L et al.; Methanol is an important anaerobic substrate in industrial wastewater treatment and the natural environment . Previous studies indicate that cobalt greatly stimulates methane formation during anaerobic treatment of methanolic wastewaters . To evaluate the effect of cobalt in a mixed culture, a sludge with low background levels of cobalt was cultivated in an upflow anaerobic sludge blanket reactor . Specific inhibitors in batch assays were then utilized to study the effect of cobalt on the growth rate and activity of different microorganisms involved in the anaerobic degradation of methanol . Only methylotrophic methanogens and acetogens were stimulated by cobalt additions, while the other trophic groups utilizing downstream intermediates, H2-CO2 or acetate, were largely unaffected . The optimal concentration of cobalt for the growth and activity of methanol-utilizing methanogens and acetogens was 0.05 mg liter-1 . The higher requirement of cobalt is presumably due to the previously reported production of unique corrinoid-containing enzymes (or coenzymes) by direct utilizers of methanol . This distinctly high requirement of cobalt by methylotrophs should be considered during methanolic wastewater treatment . Methylotroph methanogens presented a 60-fold-higher affinity for methanol than acetogens . This result in combination with the fact that acetogens grow slightly faster than methanogens under optimal cobalt conditions indicates that acetogens can outcompete methanogens only when reactor methanol and cobalt concentrations are high, provided enough inorganic carbon is available.

Am J Ind Med, 1994 Jan, 25(1), 125 - 7
Microbiological treatment of recirculating wastewater from cleaning rolls in a rolling mill; Lundholm M et al.; In industry, the use of biological methods for cleaning wastewater is increasing . The number of airborne Gram-negative bacteria was high in relation to the use of high pressure water in a rolling mill using recirculated water for cleaning rolls . Analyzing the total amount and species of microorganisms indicates whether they are emitted from a polluted source or consist of the normal airborne flora.

Salud Publica Mex, 1994 Jan-Feb, 36(1), 3 - 9
{Epidemiologic setting of the agricultural use of sewage: Valle del Mezquital, Mexico}; Cifuentes E et al.; Wastewater from Mexico City is used to irrigate over 85,000 hectares mainly of fodder and cereal crops in the Mezquital Valley . A cross-sectional study method is being used to test the impact of exposure to raw wastewater and wastewater from storage reservoirs on diarrheal disease and parasitic infections in farmworkers and their families . The study population in the rainy season survey included 1,900 households: 680 households where the farmworker is exposed to untreated wastewater (exposed group), 520 households exposed to reservoir water (semiexposed group), and 700 households where the farmworker practices rain-fed agriculture (control group) . Preliminary analysis of the data from the rainy season study (dry season study in progress) has been carried out . Current information indicates that the risk of Ascaris lumbricoides infection is much higher in the exposed group than in the control group (95% CL = 2.9-10.8) . According to the procedures employed Entamoeba histolytica infection was more frequent among subjects aged 5 to 14 years from households exposed to raw wastewater, than among subjects of the same ages belonging to the control group (95% CL = 1.07-1.72) . When diarrheal disease rates were analyzed, children under 5 years from exposed households had a significantly higher prevalence than controls (95% CL = 1.03-1.64) . The final results of this study are expected to aid decisions within the National Wastewater Reuse Programme in Mexico.(ABSTRACT TRUNCATED AT 250 WORDS)

Appl Biochem Biotechnol, 1994 Spring, 45-46, 847 - 59
Biosorption of nickel in complex aqueous waste streams by cyanobacteria; Corder SL et al.; A study was undertaken to determined if a suitable biosorbent could be found for removal of nickel at low concentrations (< 20 parts per million {ppm}) from a chemically complex wastewater effluent generated by electroplating operations . Algae and cyanobacteria were chosen as candidate biosorbent materials because they are easy to grow and they have the ability to withstand processing into biosorbent materials . Several species were screened for nickel-biosorption capacity initially, and three species of cyanobacteria were selected for further study based on their performance in the scoping tests . When compared to live controls, autoclaving improved the binding capacities of all three species, but usually biosorption data from experiments with live cells were more consistent . None of the three species was able to bind nickel efficiently in actual effluent samples . Further experimentation indicated that sodium ions, which were present in high concentrations in the effluent, were interfering with the ability of the cells to bind nickel . Adsorption isotherm plots for biosorption of nickel by two species of Anabaena in NiCl2-deionized water solutions were prepared.

Biomed Mater Eng, 1994, 4(2), 127 - 37
Removal of pesticides from wastewater at golf courses using plants (removal by mung beans; Phaseolus radiatus L); Azuma T et al.; Many studies have been done on the removal of pollutants from wastewater using aquatic plants . Water hyacinth has been the most widely-used plant, and systems using water hyacinth are well-established . These systems, however, have a few problems in their practical use . In a previous paper, we proposed a new system that could be used as a substitute for a conventional system or, as a secondary system to assist the conventional one . Mung beans will be used to remove pollutants in this system . In the previous experiment, the removal characteristics of nutrient salts such as NO2-, NO3-, NH4+ and phosphorus salts from wastewater in residential areas were examined . Mung beans exhibited good characteristics for removing these nutrient salts . At present, pesticides used at golf courses have become a severe environmental problem polluting water supplies . The purpose of this study was, therefore, to verify whether our new system using mung beans was also effective in removing pesticides from wastewater at golf courses . An experiment was conducted on seven different pesticides . They were three insecticides; Diazinon, Fenitrothion and Chlorpyrifos, three fungicides; Captan, Isoprothiolane and Chlorothalonil, and a herbicide; Simazine . The experimental results showed that, under experimental conditions, the pesticides were rapidly removed and that they exhibited no harmful effects on the growth of the mung beans . Mung beans may be used, therefore, to remove pesticides from wastewater at golf courses although further research is needed.

Hereditas, 1994, 121(3), 249 - 54
Screening of toxicity and genotoxicity in wastewater by the use of the Allium test; Nielsen MH et al.; Wastewater was collected from two municipal wastewater treatment plants and twelve different industries representing five lines of business (chemical, metallic, petrochemical, pulp- and paper, and textile dye industries) . Effect on the growth of Allium roots was measured after five days of exposure . Growth inhibition values, EC50 and EC30, showed no toxic effect for eight of the fourteen plants . The most toxic effect was found in wastewater from one of the pulp- and paper plants . Allium root tip cells were analyzed for chromosome aberrations after 24 h of exposure . Wastewater from nine of the fourteen plants was able to induce chromosome aberrations at a statistically significant level . The textile dye industry was the only line of business which did not show any genotoxic effect . Three of the plants (municipal wastewater, metallic, and pulp- and paper) showed genotoxicity in spite of being nontoxic in the growth inhibition experiment.

J Infect Dis, 1993 Dec, 168(6), 1510 - 4
Direct detection of wild poliovirus circulation by stool surveys of healthy children and analysis of community wastewater; Tambini G et al.; Cartagena, Colombia, was one of the last cities in the Americas known to have endemic poliomyelitis . After 3 cases were identified in 1991, two approaches for detecting continued silent transmission of wild polioviruses within a high-risk community were used: stool surveys of healthy children and virologic analysis of community sewage . Wild type 1 polioviruses were isolated from 8% of the children studied and from 21% of sewage samples . The proportions of wild polioviruses, vaccine-related polioviruses, and nonpolio enteric viruses were similar for both approaches . Wild poliovirus sequences were also amplified directly from processed sewage samples by the polymerase chain reaction using primer pairs specific for the indigenous type 1 genotype . The last reported cases associated with wild polioviruses in the Americas occurred in Colombia (8 April 1991) and Peru (23 August 1991) . Direct sampling for wild polioviruses in high-risk communities can provide further evidence that eradication of the indigenous wild polioviruses has been achieved in the Americas.

Appl Environ Microbiol, 1993 Nov, 59(11), 3744 - 9
Genetic improvement of Escherichia coli for enhanced biological removal of phosphate from wastewater; Kato J et al.; The ability of Escherichia coli MV1184 to accumulate inorganic phosphate (Pi) was enhanced by manipulating the genes involved in the transport and metabolism of Pi . The high-level Pi accumulation was achieved by modifying the genetic regulation and increasing the dosage of the E . coli genes encoding polyphosphate kinase (ppk), acetate kinase (ackA), and the phosphate-inducible transport system (pstS, pstC, pstA, and pstB) . Acetate kinase was employed as an ATP regeneration system for polyphosphate synthesis . Recombinant strains, which contained either pBC29 (carrying ppk) or pEP02.2 (pst operon), removed approximately two- and threefold, respectively, more Pi from minimal medium than did the control strain . The highest rates of Pii removal were obtained by strain MV1184 containing pEP03 (ppk and ackA) . However, unlike the control strain, MV1184 (pEP03) released Pi to the medium after growth had stopped . Drastic changes in growth and Pi uptake were observed when pBC29 (ppk) and pEP02.2 (pst operon) were introduced simultaneously into MV1184 . Even though growth of this recombinant was severely limited in minimal medium, the recombinant could remove approximately threefold more Pi than the control strain . Consequently, the phosphorus content of this recombinant reached a maximum of approximately 16% on a dry weight basis (49% as phosphate).

Salud Publica Mex, 1993 Nov-Dec, 35(6), 614 - 9
{The health problems associated with irrigation with wastewater in Mexico}; Cifuentes E et al.; Over 85,000 hectares in the Mezquital Valley of central Mexico are irrigated with wastewater . The main crops are fodder and cereal crops . A two cross-sectional survey was carried out to test the impact of exposure to raw wastewater and from storage of that wastewater in reservoirs . The main outcomes were diarrhoeal disease and parasitic infections in farmworkers and their families . The total study population in the dry season included 2,049 households . The study population was classified in households where the farmworker is exposed to untreated wastewater (exposed group), households exposed to reservoir water (semi-exposed group), and households where the farmworker practices rain-fed agriculture (control group) . Preliminary analysis of the data has been carried out . Current information indicates that the risk of Ascaris lumbricoides infection is much higher in the exposed group than in the control group (95% CL = 4.0-67.3 and 4.7-78.8) . According to the procedures employed, exposed children from exposed households were at higher risks of diarrhoeal disease than controls (95% CL = 1.03-2.03) . The final results of this study are expected to aid decisions within the reuse programmes in developing countries.

Arch Environ Contam Toxicol, 1993 Sep, 25(3), 293 - 7
Genotoxicity of blue rayon extracts from river waters using sister chromatid exchange in cultured mammalian cells; Ohe T et al.; Using cultured Chinese hamster lung (CHL) cells, sister chromatid exchange (SCE) assays were carried out with blue rayon extracts recovered at seven sampling locations from the Katsura, Nishitakase and Kamo Rivers, tributaries of the Yodo River, in Kyoto City, Japan . The downstream extracts of wastewater treatment plants showed higher SCE frequencies than the upstream extracts both with and without metabolic activation, suggesting that the effluents from wastewater treatment plants were the possible pollution sources of genotoxic chemicals in the rivers . The results show the possible use of SCE in CHL cells for the monitoring of genotoxicity of blue rayon extracts from river waters . In addition, simultaneous treatment with sodium thiosulfate significantly reduced the frequencies of SCE induced by blue rayon extracts.

Appl Environ Microbiol, 1993 Aug, 59(8), 2607 - 13
Purification and characterization of a phenoloxidase (laccase) from the lignin-degrading basidiomycete PM1 (CECT 2971); Coll PM et al.; A new lignin-degrading basidiomycete, strain PM1 (= CECT 2971), was isolated from the wastewater of a paper factory . The major ligninolytic activity detected in the basidiomycete PM1 culture supernatant was a phenoloxidase (laccase) . This activity was produced constitutively in defined or complex media and appeared as two protein bands in native gel electrophoresis preparations . No enzyme induction was found after treatment with certain potential laccase inducers . Laccase I was purified to homogeneity by gel filtration chromatography, anion-exchange chromatography, and hydrophobicity chromatography . The enzyme is a monomeric glycoprotein containing 6.5% carbohydrate and having a molecular weight of 64,000 . It has an isoelectric point of 3.6, it is stable in a pH range from 3 to 9, and its optimum pH is 4.5 . The laccase optimal reaction temperature is 80 degrees C, the laccase is stable for 1 h at 60 degrees C, and its activity increases with temperature . Spectroscopic analysis revealed that the enzyme has four bound copper atoms, a type I copper, a type II copper, and a type III binuclear copper . The amino-terminal sequence of the protein is very similar to the amino-terminal sequences of laccases from Coriolus hirsutus and Phlebia radiata.

Appl Environ Microbiol, 1993 May, 59(5), 1437 - 43
Survival of human immunodeficiency virus (HIV), HIV-infected lymphocytes, and poliovirus in water; Moore BE; The potential for human immunodeficiency virus (HIV) to enter domestic sewers via contaminated body fluids such as blood has spurred interest in the survival of this virus in water and wastewater . This study focused on establishing the inactivation of HIV and productively infected lymphocytes in dechlorinated tap water . In addition, HIV survival was compared with that of poliovirus . Results indicated that either free HIV or cell-associated HIV was rapidly inactivated, with a 90% loss of infectivity within 1 to 2 h at 25 degrees C and a 99.9% loss by 8 h . In comparison, poliovirus showed no loss of infectivity over 24 h . The presence of human serum in tap water slowed the rate of HIV inactivation through 8 h but did not stabilize the virus through 24 h . In addition, blood from stage IV AIDS patients was introduced into tap water, and the recovery of HIV was monitored by using both an infectivity assay and polymerase chain reaction amplification of viral sequences . Virally infected cells were no longer detectable after 5 min in dechlorinated tap water, while little diminution in amplifiable sequences was observed over 2 h . Thus, detection of viral sequences by polymerase chain reaction technology should not be equated with risk of exposure to infectious HIV.

Regul Toxicol Pharmacol, 1993 Apr, 17(2 Pt 1), 157 - 80
Subsurface agricultural irrigation drainage: the need for regulation; Lemly AD; Subsurface drainage resulting from irrigated agriculture is a toxic threat to fish and wildlife resources throughout the western United States . Studies by the U.S . Department of the Interior show that migratory waterfowl have been poisoned by drainwater contaminants on at least six national wildlife refuges . Allowing this poisoning to continue is a violation of the Migratory Bird Treaty Act under U.S . Federal law . Critical wetlands and waterfowl populations are threatened in both the Pacific and Central flyways . The public is also at risk and health warnings have been issued in some locations . Subsurface irrigation drainage is a complex effluent containing toxic concentrations of trace elements, salts, and nitrogenous compounds . Some of the contaminants are classified by the U.S . Environmental Protection Agency (EPA) as priority pollutants and they can be present in concentrations that exceed EPA's criteria for toxic waste . The on-farm drainage systems used to collect and transport this wastewater provide point-source identification as well as a mechanism for toxics control through the National Pollutant Discharge Elimination System (NPDES) permit process . A four-step approach is presented for dealing with irrigation drainage in an environmentally sound manner . This regulatory strategy is very similar to those commonly used for industrial discharges and includes site evaluation, contaminant reduction through NPDES, and compliance monitoring . The EPA must recognize subsurface irrigation drainage as a specific class of pollution subject to regulation under the NPDES process . Active involvement by EPA is necessary to ensure that adequate controls on this wastewater are implemented.

Zentralbl Hyg Umweltmed, 1993 Mar, 193(6), 513 - 20
Irrigation with waste water: parasitological analysis of soil; Gaspard P et al.; In third world countries, the agricultural use of treated wastewater represents an interesting solution . A recent report of W.H.O . shows the importance of strict parasitological criteria for such reuse . The aim of this paper is to study the conditions under which Ascaris eggs have been recovered from artificially contaminated soils (sandy, clay or loamy soil, mould garden) . The eggs elution has been carried out from soil particles using various solutions (detergents, distilled water, formaldehyde, sodium hydroxide, sodium hypochlorite) . The recovery percentage analysis showed the superiority of the sodium hypochlorite solution titrating 10 chlorometric degrees, whatever the soil type . The eggs concentration in the eluates has been carried out through the flotation technique by testing various reagents with densities ranging from 1.16 to 1.44 . The zinc sulphate solution at 50%, 55% and 66% prove to be flotation agents that are well adapted to this sampling type . By carrying out the elution with a sodium hypochlorite solution titrating 10 chlorometric degrees and the concentration by flotation with a zinc sulphate solution at 55% the recovery percentages, which are independent of the parasitic load, vary from 66 to 78%.

Arch Environ Contam Toxicol, 1993 Jan, 24(1), 11 - 5
The effect of industrial pollution on mercury levels in water, soil, and sludge in the coastal area of Motril, southeast Spain; Navarro M et al.; The total concentration of mercury was determined in samples of water, soil and sludge from the Mediterranean coastal area of Southeast Spain (Motril), where Hg contamination is produced primarily by a local paper mill . Samples were taken at surface level in a 5 Km radius from the factory . The total Hg concentrations varied from 0.117 to 0.760 microgram/g in soil and sludge, and from ND to 2.088 micrograms/L in water . A negative correlation was observed between the distance of the sampling station from the mill and the concentration of Hg in the soil and sludge samples . Similarly, an increase in Hg concentration was observed in the freshwater and wastewater after passing close to the factory.

Appl Environ Microbiol, 1993 Jan, 59(1), 140 - 3
Detection and distribution of rotavirus in raw sewage and creeks in São Paulo, Brazil; Mehnert DU et al.; Rotaviruses were concentrated from 8-liter samples of raw domestic sewage and sewage-polluted creek water by adsorption to and elution from positively charged microporous filters (Zeta Plus 60S), followed by ultracentrifugation of the filter eluates . Indirect immunofluorescence and direct immunoperoxidase methods allowed detection and enumeration of rotavirus in 6 (20.6%) of 29 sewage samples and in 19 (34.5%) of 55 creek water samples . Levels of rotaviruses ranged from < 3 to 63 focus-forming units (FFU)/liter, and the geometric means were 2.2 FFU/liter in sewage, 2.9 FFU/liter at creek Tremembe, and 2.6 FFU/liter at creek Pirajussara . Wastewater samples examined during autumn and winter months showed a higher rate positivity for rotavirus than those collected in spring and summer, corresponding to the seasonal variation of rotaviral diarrhea in the city of Sao Paulo.

Microbios, 1993, 75(302), 7 - 16
The presence of high-molecular weight proteins with a strong affinity for cadmium in environmental Escherichia coli strains; Morozzi G et al.; High molecular weight proteins, with a strong affinity for cadmium, were found in two environmental strains of Escherichia coli isolated from a wastewater treatment plant and were resistant up to 128 ppm of Cd+2 . The fraction containing intracellular cadmium binding proteins was obtained by affinity chromatography and the single components of the same fraction were separated by SDS-gel electrophoresis in order to calculate molecular weights ranging from 48 to 89 kD . Plasmid analysis, carried out by agarose gel electrophoresis, and transformation experiments demonstrated that the plasmids, isolated from one of the strains which was resistant to tetracycline and streptomycin, are not related to the synthesis of cadmium-binding proteins.

Appl Environ Microbiol, 1992 Dec, 58(12), 3984 - 90
Presence of human immunodeficiency virus nucleic acids in wastewater and their detection by polymerase chain reaction; Ansari SA et al.; The human immunodeficiency virus type 1 (HIV-1) released by infected individuals or present in human and hospital wastes can potentially cause contamination problems . The presence of HIV-1 was investigated in 16 environmental samples, including raw wastewater, sludge, final effluent, soil, and pond water, collected from different locations . A method was developed to extract total nucleic acids in intact form directly from the raw samples or from the viral concentrates of the raw samples . The isolated nucleic acids were analyzed for the presence of HIV-1 by using in vitro amplification of the target sequences by the polymerase chain reaction (PCR) method . HIV-1-specific proviral DNA and viral RNA were detected in the extracted nucleic acids obtained from three wastewater samples by this method . The specificity of the PCR-amplified products was determined by Southern blot hybridization with an HIV-1-specific oligonucleotide probe, SK19 . The isolated nucleic acids from wastewater samples were also screened for the presence of poliovirus type 1, representing a commonly found enteric virus, and simian immunodeficiency virus, representing, presumably, rare viruses . While poliovirus type 1 viral RNA was found in all of the wastewater samples, none of the samples yielded a simian immunodeficiency virus-specific product . No PCR-amplified product was yielded when wastewater samples were directly used for the detection of HIV-1 and poliovirus type 1 . The wastewater constituents appeared to be inhibitory to the enzymes reverse transcriptase and DNA polymerase.(ABSTRACT TRUNCATED AT 250 WORDS)

J Chromatogr, 1992 Nov 20, 625(2), 247 - 55
Detection of substituted benzenes in water at the pg/ml level using solid-phase microextraction and gas chromatography-ion trap mass spectrometry; Potter DW et al.; Solid-phase microextraction (SPME) is combined with gas chromatography-ion trap mass spectrometry (GC-IT-MS) for the analysis of benzene, toluene, ethyl benzene and xylene isomers (BTEX) in water . SPME is a recent technique for extracting organics from an aqueous matrix into a stationary phase immobilized on a fused-silica fiber . The analytes are thermally desorbed directly in the injector of a gas chromatograph . The wide linear dynamic range (five orders of magnitude) and pg sensitivity of the ion trap mass spectrometer in its full scan mode is an ideal detector for identifying and quantifying the analytes extracted with an SPME device . The combined method SPME-GC-IT-MS, using fibers coated with a 100-microns polydimethylsiloxane coating, showed a limit of quantitation (LOQ) of 50 pg/ml benzene in water . This corresponds to 5 pg of benzene absorbed onto the fiber . The limit of detection (LOD) was 15 pg/ml benzene . For o-xylene spiked at 50 pg/ml in water 50 pg were absorbed by the fiber indicating an LOQ and LOD 10 times better than for benzene . The detection limits obtained exceed the requirements of both the United States Environmental Protection Agency method 524.2 and the Ontario Municipal/Industrial Strategy for Abatement program, which range from 30 to 80 pg/ml and 500 to 1100 pg/ml, respectively . The linearity of the method extended over five orders of magnitude . Relative standard deviation ranged from 2.7 to 5.2% for 15 ng/ml BTEX in water and from 5.5 to 7.5% for 50 pg/ml BTEX in water . SPME-GC-IT-MS was used to evaluate the contamination level in laboratory, potable and wastewater sources.

Appl Environ Microbiol, 1992 Nov, 58(11), 3774 - 6
Relationship between bacterial counts and endotoxin concentrations in the air of wastewater treatment plants; Laitinen S et al.; The relationship between bacterial counts and endotoxin concentrations in air samples was studied . Selective EMB medium favored the growth of a larger portion of airborne gram-negative bacteria than LES Endo or MacConkey medium and was a good predictor of the endotoxin levels determined with a chromogenic Limulus assay of the air of wastewater treatment plants . The bacterial counts determined with nonselective media correlated poorly with airborne endotoxin levels; however, R2A medium yielded higher viable bacterial counts than TYG medium . Direct counting by epifluorescence microscopy yielded the highest bacterial counts, but no correlation was obtained between total bacterial counts and endotoxin concentrations.

Mutat Res, 1992 Nov 1, 270(1), 45 - 51
Tradescantia-micronucleus (Trad-MCN) bioassay on clastogenicity of wastewater and in situ monitoring; Ruiz EF et al.; The Tradescantia-micronucleus (Trad-MCN) bioassay was used to determine the clastogenicity of wastewater samples collected from the Arena canal which contains effluent from the industrial district Benito Juarez of the city of Queretaro, Mexico . Fifteen wastewater samples which were collected, in most cases, at bi-weekly intervals beginning in September 1986 through February 1988, after a 3-fold dilution were used to treat Tradescantia plant cuttings . The clastogenicity expressed in terms of micronucleus frequencies of treated groups (30 h of treatment without recovery time) was significantly (0.01) higher than that of the tapwater control groups . The Trad-MCN bioassay was also used for in situ monitoring of air pollutants for the clastogenicity at 3 sites near the industrial and residential areas (Flores Magon, Conalep and Bellas Artes) of the city of Queretaro . Fourteen monitoring trips were made to each of the 3 sites at monthly intervals beginning in May 1988 through June 1990 . Seasonal variation of micronucleus frequencies was exhibited with the peak clastogenicities shown in May and June 1988, June 1989 and April 1990 at the three sites . Micronucleus frequencies of all the exposed groups at the Conalep site, a predominantly industrial area, were markedly higher than that of the laboratory control groups throughout the 2-year period.

J Virol Methods, 1992 Oct, 40(1), 31 - 6
Improved method for coliphage detection based on beta-galactosidase induction; Ijzerman MM et al.; An improved method for coliphage detection based on the induction of beta-galactosidase in Escherichia coli is described . Upon infection by coliphages, the cells are lysed and a stable indolyl product that is dark blue becomes visible within each plaque . The improved method is compared to the proposed coliphage detection procedure described in Standard Methods for the Examination of Water and Wastewater.

J Virol Methods, 1992 Oct, 40(1), 67 - 75
Processing procedures for recovering enteric viruses from wastewater sludges; Stetler RE et al.; A powdered beef extract specially formulated for recovering viruses from environmental samples and designated as beef extract V was evaluated using indigenous and viral seeded wastewater sludge samples . When beef extract V was used to process activated and aerobically digested sludge solids, virus recoveries were shown to be similar to other methods that used commercially available supplemented beef extract . When used to process other sludge solids (primary and activated without primary clarification), cytotoxicity resulted in the BGM cell line used for virus assay . When these sludge solids were processed with the supplemented commercially marketed beef extract cell toxicity did not occur . Metal concentrations in the processed sewage sludge eluates were analyzed, but based on the levels observed they could not be shown as the source of the cytotoxicity . This did not exclude possible synergistic cytotoxic effects or organometal complexes . The commercially marketed beef extract was supplemented with either a floccing aid (FeCl3), a filter aid (Celite) or a floc prepared from paste beef extract . The paste beef floc supplement proved to be the most useful and reliable method for processing for viruses from wastewater sludge solids.

Ecotoxicol Environ Saf, 1992 Oct, 24(2), 234 - 42
Primary chemical and physical characterization of acute toxic components in wastewaters; Svenson A et al.; A chemical and physical primary characterization work sheet was developed based on the Microtox test, a bacterial bioluminescence system used as a rapid estimate of acute aquatic toxic effects . Measurements of the variation in light reduction upon different pretreatments provided information about the chemical and physical properties of the main toxic component(s) in test wastewater samples . This primary characterization of a wastewater sample was performed within 1 day . Tests of pure toxic chemical compounds and wastewaters with known and unknown primary toxicants are presented . Outlines to the chemical analysis and identification of toxic components may be deduced from the primary characterization . The provisional characterization may also provide information on wastewater treatment techniques.

J Chromatogr, 1992 Sep 16, 580(1-2), 215 - 28
Strategies for the identification of non-polar toxicants in aqueous environmental samples using toxicity-based fractionation and gas chromatography-mass spectrometry; Lukasewycz M et al.; Toxicity-based fractionation is a useful tool for the isolation and identification of non-polar organic compounds that are present at toxic concentrations in aqueous environmental samples . Methods for isolating such toxicants from the aqueous sample matrix and techniques for fractionating the compounds for the purpose of reducing the complexity of the sample matrix and thus facilitating identification are evaluated . Strategies for analyzing gas chromatographic-mass spectrometric data and confirming toxicant identification are presented . Studies that use toxicity-based fractionation for identifying the cause of toxicity in aqueous environmental samples such as municipal and industrial wastewater treatment plant effluents and ambient waters are discussed.

J Appl Bacteriol, 1992 Sep, 73(3), 257 - 62
Sensitivity of Escherichia coli cells to seawater closely depends on their growth stage; Gauthier MJ et al.; Sensitivity of Escherichia coli cells in seawater, considered in terms of culturability loss, was examined after different growth periods in a mineral medium supplemented with glucose (M9) at 37 degrees C under aerobic or anaerobic conditions . Their sensitivity varied considerably during the different growth phases and differed when cells were grown under aerobic or anaerobic conditions . Sensitivity of aerobic cells rapidly increased during the lag phase, then decreased during the exponential phase and became minimal during the stationary phase . Coliforms isolated from human faeces showed a similar sensitivity after incubation in wastewater at 37 degrees C for 3 h . The sensitivity phase was completely eliminated when cells were incubated with chloramphenicol . Variation of sensitivity in anaerobic cells according to their growth phase was comparable with that found for aerobic cells which had been left in seawater for a long period (6 d) . However, for shorter periods in this medium (1-2 d), cells grown until the mid-exponential phase remained resistant to seawater . During the second half of the growth phase, they were as sensitive as aerobic cells at lag phase . Escherichia coli cells grown under anaerobic conditions, such as found in the intestine, progressively adapt to aerobic conditions after their transfer into aerated seawater and their sensitivity to seawater increases . On a practical level, these observations show that it is necessary to control accurately the age of cells before inoculation in seawater microcosms to conserve a comparative value in results . The importance of this factor is vital as all variations in sensitivity of cells to seawater according to their prior growth phase proved to be logarithmic functions of time.

Ecotoxicol Environ Saf, 1992 Aug, 24(1), 63 - 71
Toxic effects of bleached and unbleached paper mill effluents in primary cultures of rainbow trout hepatocytes; Pesonen M et al.; Toxic effects of unbleached (sulfate or sulfite) and bleached (sulfate) paper mill effluents were studied in a primary culture of rainbow trout liver cells . The effluents and control water from a clean area were extracted with diethyl ether and added to the cultures dissolved in dimethyl sulfoxide . Plasma membrane integrity was studied by measuring lactate dehydrogenase (LDH) leakage . The cellular content of glutathione (GSH) was used as an indicator of oxidative stress and the formation of reactive intermediates . Dose-response studies indicated that unbleached effluents contained more potent toxic substances than bleached effluents . Both unbleached and bleached effluents contained organic diethyl ether-extractable substances which increased cytochrome P450-dependent 7-ethoxyresorufin-O-deethylase (EROD) activities . The inducing effects were seen at concentrations substantially lower than those decreasing GSH content and increasing LDH leakage . Possible EROD inducing substances in bleached effluents are chlorinated organic compounds . Inducing compounds in unbleached effluents are yet to be identified . Furthermore, at higher concentrations the effluents contained substances that inhibited the cytochrome P450 system . The results show that the trout primary hepatocyte cultures afford a convenient in vitro method for screening cytochrome P450 inducing components extracted from industrial effluents to investigate mechanisms by which wastewaters cause injury in cells.

Biomed Environ Sci, 1992 Jun, 5(2), 99 - 108
Removal of Cu and Ni by free and immobilized microalgae; Wong MH et al.; The present investigation evaluated the effectiveness of Chlorella cells in concentrating Cu and Ni in their cells and thereby removing the two metals from solution . The removal efficiency of the two metals by free and immobilized algal cells were further studied . (1) Four types of Chlorella cells, namely Chlorella pyrenoidosa (26) (from Carolina Biological Supplies Company), Chlorella HKBC-1 and-2 (isolated from a polluted stream receiving wastewater from several electroplating factories) and Chlorella HKBC-3 (from a clean water pond) were subjected to different concentrations of Cu and Ni accordingly . It was revealed that Chlorella HKBC-1 was the most tolerant species to Cu and Ni as reflected by their highest values of 48 h and 96 h "Highest no effect concentrations" (The highest concentration of the tested substance that does not inhibit the growth rate of the alga: Cu 2 and Ni 10 mg/l at 48 h, Cu 2 and Ni 5 at 96 h) . This was followed by C . pyrenoidosa (26) and then C . HKBC-2 while C . HKBC-3 had the lowest tolerance to the two metals (Cu 0.5 and Ni 2 at 48 h; Cu 0.5 and Ni 1 mg/l at 96 h) . (2) It was further revealed that C . HKBC-1 had higher concentration factors and removal efficiencies of Ni (734-963 mg/l, 16.3-18.7%) and C . HKBC-2 had higher concentration factors and removal efficiencies of Cu (2316-2839 mg/l, 53.7-66%) when exposed to lower concentrations of Cu (0.5, 1 and 2 mg/l) and Ni (5, 10 and 13 mg/l) . (3) By treating the free and immobilized algal cells (algal cells entrapped in alginate beads) with different concentrations of Cu and Ni, it was observed that free cells had higher concentration factors and removal efficiencies when compared with immobilized cells (free cells: Cu 1577-3056 mg/l, 24.2-71.4%; Ni 355-849 mg/l, 4.8-18.7%; immobilized cells: Cu 453-935 mg/l, 13.9-53.2%; Ni 244-486 mg/l, 3.2-11.9%).

Health Phys, 1992 Mar, 62(3), 235 - 8
Discovery of a 137Cs hot particle in municipal wastewater treatment sludge; Larsen IL et al.; Analysis of primary treatment sludge from a municipal wastewater treatment plant revealed elevated 137Cs concentrations in one sample . This elevated activity was associated with a radioactive particle that, when isolated and quantified, was found to contain 1.82 kBq of 137Cs . Additional analysis indicated an absence of alpha activity, and energetic beta radiation, if present, was less than the 137Cs activity . The particle was approximately 50 microns in diameter, appeared not to be an aggregate, and was nonmetallic.

J Bacteriol, 1992 Mar, 174(6), 1783 - 92
Isolation and comparison of the paracrystalline surface layer proteins of freshwater caulobacters; Walker SG et al.; Several methods for isolation of the paracrystalline surface (S) layer protein (RsaA) of Caulobacter crescentus CB15A were evaluated . Treatment of cells with HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid) buffer at pH 2 was the most effective means of selectively removing RsaA from cells, and after neutralization, the protein was capable of reassembling into a paracrystalline structure . Ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid treatment could also be used to extract RsaA and yielded protein capable of reassembly . The success of the methods was likely related to disruption of calcium-mediated bonding; calcium was required for recrystallization, while magnesium and strontium ions were ineffective . Antibody was raised against purified RsaA and, along with the S-layer extraction techniques, was used to evaluate 42 strains of caulobacters isolated from a variety of aquatic and wastewater treatment locations . A single characteristic protein could be isolated from the 35 strains that produced an S layer; with one exception, no proteins were extracted from strains that had no S layer . The presumed S-layer proteins ranged in size from 100 to 193 kDa . All of these proteins specifically reacted with anti-RsaA serum by Western immunoblot analysis . In strain CB15A, a specific S-layer-associated oligosaccharide has been proposed to be involved in a calcium-mediated attachment of the S layer to the cell surface . This molecule was detected by Western immunoblotting with a specific antiserum and on polyacrylamide gels stained for polysaccharides . A comparable band was found in all S-layer-producing strains and for most, S-layer-associated oligosaccharide-specific antibody reacted with them in Western analysis . Overall, in freshwater caulobacters at least portions of their S-layer structures appear to be strongly conserved entities, as well as the means of attachment to the cell surface.

Fundam Appl Toxicol, 1992 Feb, 18(2), 189 - 92
Acrylamide: dermal exposure produces genetic damage in male mouse germ cells; Gutierrez-Espeleta GA et al.; Acrylamide is used extensively in sewage and wastewater treatment plants, in the paper and pulp industry, in treatment of potable water, and in research laboratories for chromatography, electrophoresis, and electron microscopy . Dermal contact is a major route of human exposure . It has been shown that acrylamide is highly effective in breaking chromosomes of germ cells of male mice and rats when administered intraperitoneally or orally, resulting both in the early death of conceptuses and in the transmission of reciprocal translocations to live-born progeny . It is now reported that acrylamide is absorbed through the skin of male mice, reaches the germ cells, and induces chromosomal damage . The magnitude of genetic damage appears to be proportional to the dose administered topically.

Anal Chem, 1992 Jan 1, 64(1), 36 - 43
Nitroprusside and methylene blue methods for silicone membrane differentiated flow injection determination of sulfide in water and wastewater; Kuban V et al.; Hydrogen sulfide evolved from an acidified sample is pre-concentrated by permeation in a stationary alkaline acceptor solution enclosed in a silicone rubber sample loop . Depending on the sample volume pre-concentrated, the applicable analytical range spans low micrograms/L to tens of mg/L for both methods . The methylene blue method is more sensitive by a factor of approximately 30 and actually permits practical determinations in the sub-micrograms/L levels . The limit of detection (LOD) for the nitroprusside method ranges from 20 micrograms/L for a 20 microL sample by conventional flow-injection determination (no membrane, throughput 30 samples/h) to less than 2 micrograms/L for 12 mL sample pre-concentrated in the membrane system (throughput 5 samples/h) . The membrane is highly resistant to fouling and permits analysis of untreated wastewater samples bearing suspended solids, oil, grease, etc . without any pretreatment . No significant interference is observed with either chemistry . Although the nitroprusside chemistry is less sensitive, it does not involve the use of concentrated aggressive reagents and is recommended unless ultratrace determinations are essential . Viable reaction mechanisms are proposed for both of these chemistries.

ISA Trans, 1992, 31(1), 111 - 23
Instrumentation control and automation in the control of biological effluent treatment; Briggs R et al.; The role of instrumentation, control, and automation (ICA) in the management, operation, and control of domestic and industrial wastewater treatment works is examined following an historical account of developments in the UK over the past two decades . Included also are aspects of process optimization and process selection, taking into account size and types of works and populations served . The particular ICA requirements of individual unit processes are examined and the effects of unattended operation and remote supervision are considered . Particular attention is paid to measurement technology, the shortcomings of available instruments and systems, and recent developments of relevance, with particular emphasis being placed on microelectronic and fibre- and electro-optic-based sensors and on the role of advanced commenting methods including expert systems . Progress with biologically based sensors is also discussed.

Appl Environ Microbiol, 1992 Jan, 58(1), 365 - 70
Influence of a supplemental carbon source on anaerobic dechlorination of pentachlorophenol in granular sludge; Hendriksen HV et al.; Anaerobic dechlorination of pentachlorophenol (PCP) was studied in two upflow anaerobic sludge blanket reactors . One reactor received glucose (0.9 g liter-1) as an additional carbon source; the other one served as a control . The concentration of PCP in the medium was 4.5 and 3.0 mg liter-1 in the experimental and control reactors, respectively . The reactors were inoculated with granular sludge previously grown on sugar-containing wastewater . After 10 months of continuous operation, the removal of PCP was 99% in the glucose-amended reactor, whereas the removal in the control reactor varied between 32 and 77% . Furthermore, 94% of the PCP was completely dechlorinated in the glucose reactor compared with a maximum of 20% in the control reactor . In the same period, the amount of biomass in the glucose reactor had increased by approximately 150% compared with that in the control reactor, where no growth of the sludge bed occurred . Batch culture activity tests showed that the addition of glucose had a stimulatory effect on the dechlorination rate of PCP per gram of volatile solids . This indicated that the better performance of the glucose-amended reactor was due to a higher concentration of biomass and a direct stimulatory effect of glucose on the dechlorination rate . The pattern of dechlorination of PCP showed that an initial para cleavage was followed by two ortho cleavages.

Arch Environ Contam Toxicol, 1992 Jan, 22(1), 107 - 13
The relative sensitivity of competing hydropsychid species to fluoride toxicity in the Cache la Poudre River (Colorado); Camargo JA et al.; The influence of increased fluoride concentrations generated by a wastewater treatment plant on the spatial distribution and abundance of benthic larvae of Hydropsychidae (Insecta, Trichoptera) species in the Cache la Poudre River (Colorado) was examined . Acute lethal concentrations of fluoride ion (F-) to these species were determined in soft water (average value of hardness 40.2 mg CaCO3/L) by static toxicity bioassays . The wastewater treatment plant caused a significant (P less than 0.05) increase in the fluoride concentration at three downstream sampling sites (mean values 1.17, 0.84, and 0.56 mg F-/L at 0.1, 1.6, and 9.2 km downstream sites, respectively) compared with the upstream reference station (0.31 mg F-/L) . The 48, 72, 96, 120, and 144-h LC50s (mg F-/L) were 52.6, 25.8, 17.0, 13.4, and 11.5 for Hydropsyche bronta Ross, 102.0, 53.5, 34.7, 27.0, and 21.4 for Hydropsyche occidentalis Banks, and 128.0, 73.2, 42.5, 31.9, and 24.2 for Cheumatopsyche pettiti (Banks) . LC50 values for H . bronta were significantly (P less than 0.05) lower than LC50 values for the other two test species . Abundance and biomass of all hydropsychid species were significantly (P less than 0.05) lower at the 0.1 km downstream site than at the upstream reference site . H . occidentalis was usually the most abundant species at the reference and 9.2 km downstream stations, with highest abundances at the 9.2 km downstream site . C . pettiti was dominant at 0.1 and 1.6 km downstream sites, showing higher abundances at the 1.6 km downstream site than at the upstream reference site . H . bronta was never collected at 0.1 and 1.6 km downstream sites, but was abundant at the upstream reference site.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomed Mater Eng, 1992 Summer, 2(2), 89 - 105
A basic study on removal of nutrient salts in wastewater using plants (removal by mung beans; Phaseolus radiatus L); Azuma T et al.; Many studies have reported on the removal of pollutants from wastewater using aquatic plants . The water hyacinth has been the most widely used and its system is the most well established . This system however, has a few problems in practical use . The purpose of this study is to obtain basic information on a new system that can substitute for a conventional system or be used as a secondary system to assist the conventional one . We first envisioned a model of this new system and then conducted a preliminary experiment using a small experimental unit to simulate the new system . The experiment showed that mung beans were a suitable plant for our study . Their removal rate of pollutants was the highest before they developed leaves and started photosynthesis . We found that nutrients were expelled outside the plant root when nutrient concentration inside the plant tissue became too high.

Schriftenr Ver Wasser Boden Lufthyg, 1992, 89, 657 - 73
{Examination of the water supply with the alkali and alkali-earth supplement optimized DIN luminescent bacteria test, exemplified by the Saar river}; Krebs F; The light intensity emitted by luminescent bacteria is influenced by both the osmolarity and the ion composition of the test medium . The addition of potassium and calcium ions to a sodium chloride solution causes a considerable increase in the light intensity of bacteria . If these elements occur in the proper concentrations in the test material, the luminescence in the test sample will be higher than in the control sample containing only sodium chloride . This physiological dependence did not find the due consideration in the establishment of the German standard method for the luminescent bacteria test using Microtox bacteria (German Institute for Standardization DIN 38,412, Part 34--edition March 1991) where only the osmotic balancing by sodium chloride was taken into account . For testing chemicals, the luminescent bacteria test with Microtox reagent can be run without problems by the procedure that is recommended by Microbics Corporation and which became part of the DIN standard method . The situation is different when analyses of natural waters or effluents from wastewater plants are concerned, where matrix effects have to be expected . Stimulation of light intensity can be a reflection of a nonoptimized test medium and in the worst case may cause false negative results . The new ASW (artificial sea-water) luminescent bacteria medium according to Klein, which besides sodium contains potassium, magnesium, and calcium ions, brings stimulation to both samples and controls, effectively reducing enhancement and increasing the inhibitory effects of samples from the River Saar . However, high light stimulation rates measured in parallel tests with the DIN procedure could not be caused by the low concentrations of alkaline and alkaline-earth ions in the samples . The experiments indicate that there must be additional influencing substances which have not yet been identified . Furthermore, the experiments show that the matrix effects of unknown origin that will exert a positive influence on the light emission may be compensated by addition of alkaline and alkaline-earth ions.

IARC Sci Publ, 1992, (118), 133 - 48
Sources of cadmium, its distribution and turnover in the freshwater environment; Muntau H et al.; Cadmium enters the aquatic environment from numerous sources, e.g., via the atmosphere, from which the cadmium released by combustion, mainly of fossil fuels, is deposited . Since some fertilizers contain up to 40 mg/kg cadmium, wash-out from agricultural land is another source . Zinc ores contain up to several percent of cadmium, and there may be high concentrations in raw zinc, zinc alloys and zinc compounds, so that cadmium may enter the aquatic environment from mining residues, solid wastes and wastewater discharges . Once in the aquatic environment, cadmium is highly mobile . Its dissolved species are extremely labile, and are the first to be released, e.g., when salinity increases in estuaries . Sediments reflect the metal loading in the past, and their analysis can be the key to an understanding of the fate of anthropogenic discharges into the hydrosphere . The internal cadmium loading of aquatic systems can be estimated from the remobilization rates of cadmium from sediments.

J Hyg Epidemiol Microbiol Immunol, 1992, 36(4), 330 - 7
Risk of contamination of human and agricultural environment with parasites through reuse of treated municipal wastewater in Riyadh, Saudi Arabia; Bolbol AS; Two selected sites in the Riyadh metropolitan area were surveyed for the presence of human pathogenic parasites in treated municipal wastewater (TMWW) . A total of 100 samples were collected from both sites at two different seasons, the winter and summer reason . The most common parasites seen were the larvae and adult of Strongyloides sp . There were few Ascaris lumbricoides ova, some of which were embryonated and possibly infective, while the highest frequency of Ascaris ova (100 +/litre) was found at site 2 h, the highest frequency of Strongyloides sp . larvae (36-72/litre) and Strongyloides sp . adult (100 +/litre) were found at sites 2 W and 1 W respectively . The variation between sites and seasonal fluctuations showed a significant difference in parasite per litre . High atmospheric temperatures in the Riyadh area seem to be lethal to most intestinal pathogens similarly the absence of protozoal cysts in the TMWW could be attributed to certain treatment processes and other environmental factors . Data obtained from this study will be valuable in planning for the control of parasitic diseases in particular and public health pathogens in general.

Ecotoxicol Environ Saf, 1991 Dec, 22(3), 309 - 19
Application of the Hydra attenuata assay for identifying developmental hazards among natural waters and wastewaters; Fu LJ et al.; This study concerns application of the Hydra attenuata assay to detect the developmental toxicity potential of various aqueous samples . First, the assay was modified for testing aqueous samples because water quality has a major impact on aquatic toxicity testing and the results thus obtained . Ranges of sample pH, salinity (conductivity), and hardness were examined for their adverse effects upon the hydra . Adult hydra were unaffected morphologically by pH 5.5-9.5, and the artificial embryo ("embryo") developed normally in a pH range of 6.25 to 8.25 . For water hardness, the minimal affective concentration was 1000 mg/liter (as CaCO3) in adults and 625 mg/liter in the embryos; the NOAELs for these were 750 mg/liter in the adult and 250 mg/liter CaCO3 in the embryo . Salinity in excess of 5 ppt was lethal to adults and embryos, indicating the assay may not be applicable to marine or highly saline samples . Finally, grab samples were tested from rivers in Maryland, Pennsylvania, New Jersey, and Delaware, some of which are impacted by industrial and agricultural activities, as well as several samples of industrial wastewaters from one major facility . The assay functioned normally with these diverse samples and yielded results that can be used in assessing the potential developmental hazard of these materials.

Text Rent . 1992 Jan;75(5):36, 38, 40 passim.
Wastewater treatment systems; Casaday JE; Textile rental operators face tough wastewater cleanup challenges in many communities nationwide . Depending on the local POTW regulations and the textile rental company's customer base, wastewater pretreatment isn't always necessary . However, many plants must pretreat or risk being put out of business . In this article, eight manufacturers of wastewater treatment equipment explain their systems to help industry operators comply with POTW limits.

Appl Biochem Biotechnol, 1991 Dec, 31(3), 223 - 35
Olive milling wastewater as a medium for growth of four Pleurotus species; Sanjust E et al.; Four species of Pleurotus were adapted to grow on olive milling wastewater, and in certain conditions produced high yield of fruit bodies . Some biochemical transformations were observed in the olive milling wastewater owing to the growth of Pleurotus . In particular, the fungi actively excreted large amounts of laccase in the medium, and at the same time the concentration of phenolics and other toxic compounds significantly decreased, as revealed by HPLC analysis and toxicity tests on standard cultures of human cell lines.

Appl Environ Microbiol, 1991 Dec, 57(12), 3438 - 49
Characterization of metabolic performance of methanogenic granules treating brewery wastewater: role of sulfate-reducing bacteria; Wu WM et al.; Granules from an upflow anaerobic sludge blanket system treating a brewery wastewater that contained mainly ethanol, propionate, and acetate as carbon sources and sulfate (0.6 to 1.0 mM) were characterized for their physical and chemical properties, metabolic performance on various substrates, and microbial composition . Transmission electron microscopic examination showed that at least three types of microcolonies existed inside the granules . One type consisted of Methanothrix-like rods with low levels of Methanobacterium-like rods; two other types appeared to be associations between syntrophic-like acetogens and Methanobacterium-like organisms . The granules were observed to be have numerous vents or channels on the surface that extended into the interior portions of the granules that may be involved in release of gas formed within the granules . The maximum substrate conversion rates (millimoles per gram of volatile suspended solids per day) at 35 degrees C in the absence of sulfate were 45.1, 8.04, 4.14, and 5.75 for ethanol, acetate, propionate, and glucose, respectively . The maximum methane production rates (millimoles per gram of volatile suspended solids per day) from H2-CO2 and formate were essentially equal for intact granules (13.7 and 13.5) and for physically disrupted granules (42 and 37) . During syntrophic ethanol conversion, both hydrogen and formate were formed by the granules . The concentrations of these two intermediates were maintained at a thermodynamic equilibrium, indicating that both are intermediate metabolites in degradation . Formate accumulated and was then consumed during methanogenesis from H2-CO2 . Higher concentrations of formate accumulated in the absence of sulfate than in the presence of sulfate . The addition of sulfate (8 to 9 mM) increased the maximum substrate degradation rates for propionate and ethanol by 27 and 12%, respectively . In the presence of this level of sulfate, sulfate-reducing bacteria did not play a significant role in the metabolism of H2, formate, and acetate, but ethanol and propionate were converted via sulfate reduction by approximately 28 and 60%, respectively . In the presence of 2.0 mM molybdate, syntrophic propionate and ethanol conversion by the granules was inhibited by 97 and 29%, respectively . The data show that in this granular microbial consortium, methanogens and sulfate-reducing bacteria did not compete for common substrates . Syntrophic propionate and ethanol conversion was likely performed primarily by sulfate-reducing bacteria, while H2, formate, and acetate were consumed primarily by methanogens.

J Am Mosq Control Assoc, 1991 Dec, 7(4), 608 - 15
Measuring mosquito dispersal for control programs; Morris CD et al.; Simple and economic methods were developed for control programs to demonstrate the movement of mosquitoes from a breeding source to residential areas . Using mark-release-recapture methods and examples, mean, median and maximum distances traveled were estimated or observed and compared for 11 species produced in a wastewater treatment facility near Lakeland, FL . The applicability of these methods and data interpretation for operational mosquito control programs are discussed.

Am J Epidemiol, 1991 Oct 15, 134(8), 887 - 94
The role of home environment in infant diarrhea in rural Egypt; Wright CE et al.; In 1982 and 1983, a descriptive environmental survey was conducted in 317 households with newborn infants in rural Bilbeis, Egypt . The incidence of infant diarrhea in these households was ascertained by twice-weekly home visits for a 1-year period (1981-1982) . Using univariate and multivariate analyses, the authors identified household factors that were statistically associated with infant diarrhea incidence, including number of children in the house under 4 years of age; number of persons per household; incidence of diarrhea in other family members; having a dirt (vs . concrete) dining room floor; having multiple living areas in the house; having a house or roof in need of repair; using well water rather than tap water for cooking or bathin; the absence of a sewer for waste bathwater; food being left out at room temperature between meals; and having many rodents in the house . Two practices involving interaction with the environment appeared to be protective: butchering of cattle by the family for home consumption, and protection of the infant from flies by a veil during napping . The combined household variables explained 25% of the variance in the total incidence of diarrhea . Categories of variables that accounted for most of the total variance explained by environmental factors are, in decreasing order: house structure (28%); water usage (24%); toilet and bathing area (12%); animal management (11%); food preparation area (10%); hygiene (8%); and wastewater management (6%) . This approach may be useful in identifying environmental characteristics whose change would reduce diarrheal illness among infants.

Text Rent, 1991 Oct, 75(2), 44 - 6, 48, 50-2
Wastewater treatment methods from A to Z; Blaco CE; With local wastewater disposal regulations varying from nonexistent to nightmarish, operators must choose the method of treatment that best suits their needs . Various types of wastewater pretreatment equipment and processes are currently used in rental and commercial laundries . Here's information on systems ranging from simple settling pits and screens to sophisticated membrane filtration systems.

Text Rent, 1991 Oct, 75(2), 36, 38, 40 - 2
Pretreatment standards: categorical regulations on the horizon; Casaday JE; As Congress writes aggressive wastewater laws and EPA tightens its regulatory grip, the question of whether to fight or compromise becomes even more pressing for the textile rental industry . As Congress moves forward on the reauthorization of the Clean Water Act, EPA's authority to issue pretreatment standards could be greatly strengthened . Categorical pretreatment standards would set national limits on the concentrations of various pollutants that are being discharged to publicly owned treatment works (POTWs) . As EPA lays out its recommendations to Congress, perhaps it's time for the textile rental industry to reevaluate its position on categorical standards.

J Virol Methods, 1991 Aug, 33(3), 383 - 90
Detection of nucleic acids homologous to human immunodeficiency virus in wastewater; Preston DR et al.; Raw wastewaters were obtained from the cities of Belle Glade, Ocala and Gainesville in the state of Florida and were concentrated using several established methods for the recovery of human enteroviruses . The nucleic acids were then extracted from the wastewater concentrates, suspended in 2 x SSC with and without 2 N NaOH (for the detection of DNA and both DNA and RNA, respectively), and dot blotted onto hybridization membranes . These membranes were then hybridized with three 32P-end-labeled 18-mer oligonucleotides directed against the LTR, gag, and env regions of the human immunodeficiency virus type 1 (HIV-1) . Autoradiographic analyses of these blots indicate that sequences homologous to HIV-1 genomic RNA and proviral DNA were found in Belle Glade wastewater but not in wastewater from Ocala and Gainesville . These findings may have implications in the wastewater treatment system as well as for detection of HIV-1 in clinical samples.

Appl Environ Microbiol, 1991 Jul, 57(7), 1942 - 9
Bacteriological composition and structure of granular sludge adapted to different substrates; Grotenhuis JT et al.; The bacteriological composition and ultrastructure of mesophilic granular methanogenic sludge from a large-scale Upflow Anaerobic Sludge Blanket reactor treating wastewater from a sugar plant and of sludge granules adapted to ethanol and propionate were studied by counting different bacterial groups and by immunocytochemical methods . Propionate-grown granular sludge consisted of two types of clusters, those of a rod-shaped bacterium immunologically related to Methanothrix soehngenii and those consisting of two different types of bacteria with a specific spatial orientation . One of these bacteria reacted with antiserum against Methanobrevibacter arboriphilus AZ, whereas the other is most likely a propionate-oxidizing bacterium immunologically unrelated to Syntrophobacter wolinii . Sludge granules obtained from the large-scale Upflow Anaerobic Sludge Blanket reactor and granules cultivated on ethanol did not show the typical spatial orientation of bacteria . Examination of the bacterial composition of the three types of granules by light and electron microscopy, the most-probable-number method, and by isolations showed that M . arboriphilus and M . soehngenii were the most abundant hydrogenotrophic and acetoclastic methanogens in propionate-grown sludge . Methanospirillum hungatei and Methanosarcina barkeri predominated in ethanol-grown granules, whereas many morphotypes of methanogens were abundant in granules from the full-scale reactor.

Appl Microbiol Biotechnol, 1991 Jul, 35(4), 551 - 7
Degradation of 3,4-dichloroaniline in synthetic and industrially produced wastewaters by mixed cultures freely suspended and immobilized in a packed-bed reactor; Livingston AG et al.; Degradation of 3,4-dichloroaniline (34DCA) in aqueous solution by undefined cultures of free and immobilized cells was examined . Batch cultures of freely suspended cells and continuous degradation in a packed-bed reactor were studied using both synthetically concocted and industrially produced waste-waters . 34DCA was found to be degraded with a concomitant evolution of chloride ions into the bulk medium . The packed bed reactor with biomass immobilized on celite diatomaceous earth was found to be capable of degrading over 98% of the 34DCA present in a synthetically concocted inlet stream at a concentration of 250 mg l-1 . Residence times of less than 4 h were employed, giving an overall volumetric degradation rate for the packed bed of 90 mg l-1 h-1 . The industrially produced waste-water contained, in addition to 34DCA, aniline, 4-chloroaniline, 2,3-dichloroaniline (23DCA) and 3,4-dichloronitrobenzene . The biomass enriched on the synthetic 34DCA waste-water was found to be capable of degrading these compounds in addition to 34DCA with the exception of 23DCA . 34DCA degradation efficiencies of over 95% were obtained for the industrial waste-water at reactor residence times of 4.6 h, giving volumetric degradation rates of 24 mg l-1 h-1.

J Chromatogr, 1991 Jun 21, 546(1-2), 335 - 40
Determination of dissolved hexavalent chromium in industrial wastewater effluents by ion chromatography and post-column derivatization with diphenylcarbazide; Arar EJ et al.; A proposed EPA method for the determination of dissolved hexavalent chromium in drinking water, groundwater and industrial wastewater effluents was developed using existing ion chromatographic techniques . Two solid waste matrices were briefly investigated . Aqueous samples were passed through a 0.45-micron filter and the filtrate was either (1) left unadjusted, (2) adjusted to pH 8 or (3) adjusted to pH 10 prior to analysis by ion chromatography . The method detection limits were 0.3-0.4 micrograms/l . When analyzed within 24 h, the two pH levels and the unadjusted sample yielded ca . 100% recovery of spikes . No oxidation of trivalent chromium to hexavalent chromium was observed at pH 7, 8 or 10 when aqueous samples were spiked with 50 mg/l Cr(III).

J Am Mosq Control Assoc, 1991 Jun, 7(2), 287 - 9
Vertical distribution of Psychoda alternata (Diptera:Psychodidae) in soil receiving wastewater utilized for turf cultivation; Ali A et al.; Vertical distribution of immature Psychoda alternata in soil to a depth of 15 cm was studied in Jacksonville, FL . Samples were randomly taken from large circular land areas receiving a brewery wastewater utilized for commercial turf cultivation and included turfed and bare habitats . Total organic matter was quantified at various soil depths . Overall, 88.5 and 95.8% larvae and 91.3 and 94.0% pupae were recovered from the top 2.5 cm of soil at turfed and bare habitats, respectively . The highest concentration of total organic matter at both habitat types was in the top 2.5 cm . There were strong positive relationships between the number of larvae and pupae and total organic matter, indicating highest concentrations of immatures in nutrient-rich topsoil with an abundant supply of larval food . We suggest that insecticidal treatment directed against immature P . alternata breeding in such habitats need not penetrate to a depth of more than a few centimeters to affect almost all of the population of this pestiferous insect.

Ecotoxicol Environ Saf, 1991 Apr, 21(2), 207 - 14
Studies on the environmental persistence of S-31183 (pyriproxyfen): adsorption onto organic matter and potential for leaching through soil; Schaefer CH et al.; Analytical methods were developed to allow the extraction and analysis of S-31183 (pyriproxyfen), 2-{1-methyl-2-(4-phenoxyphenoxy)ethoxy}pyridine, in organic matter from animal waste-water lagoons . Analysis of water and organic debris from a treated lagoon showed that the active ingredient readily adsorbed onto organic matter . S-31183 persisted on organic matter for over a 2-month period, during which time the concentration decayed at an exponential rate . In leaching trials with four different soil types, over 50% of the active ingredient applied remained in the upper 6 cm of a 30-cm soil column; there was no indication of a rapid potential for downward migration . The use of S-31183 for treating wastewater lagoons at doses which are effective for mosquito control did not result in any apparent problems of environmental incompatibility.

J Forensic Sci, 1991 Mar, 36(2), 343 - 9
An enzyme-linked immunosorbent assay (ELISA) for trinitrotoluene (TNT) residue on hands; Fetterolf DD et al.; An enzyme-linked immunosorbent assay (ELISA) developed for the detection of trinitrotoluene (TNT) in munitions wastewater has been adapted to the detection of TNT residue on hands following contact . Using the procedure developed, as little as 50 pg of TNT could be detected . Accounting for sample size and dilution, the 50 pg equates to 15 ng of TNT recovered from the hands . Following contact with TNT, amounts ranging from 53 ng to more than 1500 ng were recovered from hands . The monoclonal anti-TNT antibodies showed no cross-reactivity with several other explosives or common contaminants . These preliminary results indicate promise for the development of a simple-to-use, immunoassay-based field test kit for TNT and, ultimately, other explosives.

Appl Environ Microbiol, 1991 Feb, 57(2), 604 - 5
Improved method for coliform verification; Diehl JD Jr; Modification of a method for coliform verification presented in Standard Methods for the Examination of Water and Wastewater is described . Modification of the method, which is based on beta-galactosidase production, involves incorporation of a lactose operon inducer in medium upon which presumptive coliform isolates are cultured prior to beta-galactosidase assay.

J Air Waste Manage Assoc, 1991 Feb, 41(2), 228 - 33
EPA site demonstration of BioTrol aqueous treatment system; Stinson MK et al.; BioTrol's pilot scale, fixed-film biological system was evaluated, under the EPA's SITE program, for its effectiveness at removing pentachlorophenol from groundwater . The demonstration was performed in the summer of 1989 at a wood preserving site in New Brighton, Minnesota . The system employs indigenous microorganisms amended with a specific pentachlorophenol-degrading bacterium . Groundwater from a well on the site was fed to the system at 1, 3, and 5 gpm with no pretreatment other than pH adjustment, nutrient addition, and temperature control . Each flowrate was maintained for about two weeks while samples were collected for extensive analyses . At 5 gpm, the system was capable of eliminating about 96 percent of the pentachlorophenol in the groundwater and producing effluent with pentachlorophenol concentrations of about 1 ppm . At the lower flows (1 and 3 gpm) removal was higher (about 99 percent) and effluent pentachlorophenol concentrations were well below 0.5 ppm . The system consistently produced a completely nontoxic effluent at all three flowrates . Review of other data provided by BioTrol indicates that the process is also effective on other hydrocarbons, including solvents and fuels . The system appears to be a compact and cost-effective treatment for contaminated wastewaters requiring minimal operating attention once acclimated.

Environ Health Perspect, 1991 Jan, 90, 171 - 5
Statistical issues in risk assessment of reproductive outcomes with chemical mixtures; Hertzberg VS et al.; Establishing the relationship between a given chemical exposure and human reproductive health risk is complicated by exposures or other concomitant factors that may vary from pregnancy to pregnancy . Moreover, when exposures are to complex mixtures of chemicals, varying with time in number of components, doses of individual components, and constancy of exposure, the picture becomes even more complicated . A pilot study of risk of adverse reproductive outcomes among male wastewater treatment workers and their wives is described here . The wives of 231 workers were interviewed to evaluate retrospectively the outcomes of spontaneous early fetal loss and infertility . In addition, 87 workers participated in a cross-sectional evaluation of sperm/semen parameters . Due to the ever-changing nature of the exposure and the lack of quantification of specific exposures, six dichotomous variables were used for each specific job description to give a surrogate measure of exposure . Hence, no quantitative exposure-response relationships could be modeled . These six variables were independently assigned by two environmental hygienists, and their interrater reliability was assessed . Results are presented and further innovations in statistical methodology are proposed for further applications.

Am J Ind Med, 1991, 19(1), 75 - 86
Retrospective cohort mortality study of cancer among sewage plant workers; Lafleur J et al.; There is little known about the incidence of cancer among sewage workers . In this paper we examine findings from a retrospective cohort study of 487 white male sewer authority workers employed between January 1950 and October 1979 . Vital status was ascertained for 93% of the cohort yielding a total of 6,886 person years . Total mortality from all causes was comparable to that of the general white male U.S . population (Standardized Mortality Ratio {SMR} = 0.91, 95% Confidence Interval {CI} = 0.77-1.07) . The cohort was subdivided into those not exposed, and sewer workers who were exposed to sewage effluent, sludge, or wastewater containing chemicals including potential carcinogens . Among the nonexposed group, mortality from all causes was significantly low (SMR = 0.55, 95% CI = 0.33-0.88) . Among the exposed sewer workers, mortality from all causes was not significantly different from that of the general white male U.S . population (SMR = 1.00, 95% CI = 0.84-1.19) . Mortality from all cancers among exposed sewer workers was slightly higher than that of the general population (SMR = 1.19, 95% CI = 0.79-1.7) . Statistically significant elevated mortality ratios were seen for cancer of the larynx (SMR = 7.93, 95% CI = 1.59-23.96), and cancer of the liver (SMR = 5.4, 95% CI = 1.10-16.05) . Careful study of the medical and occupational histories of these cases suggested that larynx cancer was possibly work-related, while liver cancer was not . A group estimated to be the highest exposed, composed predominantly of operatives, had a higher directly adjusted death rate from all malignant neoplasms combined compared to all other workers (rate ratio = 1.64) . These findings of increased risk of cancer among exposed sewage workers, especially operators, are based on small number of cases and should be interpreted with caution . Studies of larger cohorts are needed to clarify the risk of these cancers among sewage workers.

Public Health Rev, 1991-92, 19(1-4), 243 - 50
Health impact evaluation of wastewater use in Mexico; Cifuentes E et al.; Wastewater from Mexico city is used to irrigate over 85 000 hectares, mainly of fodder and cereal crops in the Mezquital Valley . A cross-sectional study method is being used to test the impact of exposure to raw wastewater and wastewater from storage reservoirs on diarrhoeal disease and parasitic infections in farmworkers and their families . The study population in the rainy season survey included 1 900 households: 680 households where the farmworker is exposed to untreated wastewater (exposed group), 520 households exposed to reservoir water (semi exposed group), and 700 households where the farmworker practices rain-fed agriculture (control group) . Preliminary analysis of the data from the rainy season study (dry season study in progress) has been carried out . Current information indicates that the risk of Ascaris lumbricoides infection is much higher in the exposed group than in the semi-exposed and the control groups . According to the procedures employed Entamoeba histolytica infection was more frequent in individuals aged 5 to 14 years exposed to wastewater, than in those in the control group . When diarrhoeal disease rates were analyzed, children under age 15 years from exposed households had a significantly higher prevalence than controls . The final results of this study are expected to aid decisions on low cost treatment options and other health protection measures within the National Wastewater Reuse Programme in Mexico . The implications for assessment of the WHO guidelines for the use of wastewater in agriculture are discussed.

Public Health Rev, 1991-92, 19(1-4), 237 - 42
Recent epidemiological studies to test microbiological quality guidelines for wastewater use in agriculture and aquaculture; Blumenthal UJ et al.; BACKGROUND: New guidelines for wastewater reuse (WHO 1989) are controversial . Epidemiological studies are needed to test their validity . Cross-sectional studies of the impact of excreta use in aquaculture in Indonesia, and of wastewater use in irrigation in Mexico have been carried out . METHODS: Each study involved an exposed group using wastewater/excreta with no treatment, a control group with no wastes use, and an intermediate group, where wastewater/excreta was used but some health protection measure existed . In Mexico, the intermediate group used wastewater from a storage reservoir which met the new WHO guideline for restricted irrigation . In Indonesia, the intermediate group did not have domestic exposure to pondwater, whose quality was around forty times higher than the tentative WHO bacterial guideline for fishpond water . RESULTS: In Indonesia, the prevalence of diarrhoeal disease was low in adults, and unrelated to exposure, but high in children under 5 years . Multiple logistic regression analysis gave odds ratios of 1.4 (p = .06) for consumer exposure, 1.9 (p = .01) for recreational or occupational exposure and 1.6 (p = .01) for domestic exposure, when allowance was made for all other exposures and several confounding factors . In Mexico, preliminary analysis of the wet season data suggests that the increased risks of Ascaris infection and diarrhoeal disease from the use of raw wastewater are removed when water of WHO guideline quality from storage reservoirs is used . CONCLUSION: WHO (1989) guidelines can be tested using cross-sectional epidemiological studies which indicate that guidelines for restricted irrigation and for aquaculture may be around the right level.

J Tongji Med Univ, 1991, 11(3), 187 - 92
Study on mutagenicity and identification of organic pollutants in wastewater of industrial area; Tang F et al.; In this study, wastewater samples from three industrial wastewater channels and 12 related factories were collected . Nonvolatile organic chemicals were concentrated on H-103 resin and analysed by GC/MS/DS techniques . The mutagenicity of organic extracts from the samples was examined by using S . typhimurium assay (Ames test) . The results of both Ames test and chemical analysis showed that the mutagenic compounds in the Loujia Channel mainly come from Dyestuff Factory, and that Pharmaceutical Factory is a main pollution source of mutagenic compounds for the Xindun Channel . Our experimental results also showed that it is necessary to examine the mutagenicity of industrial wastewater by using short term bioassay for evaluating long-term effect of industrial wastewater on human health.

J Appl Toxicol, 1990 Dec, 10(6), 443 - 6
Proposal and application of an ecotoxicity biotest based on Escherichia coli; Espigares M et al.; The authors propose the use of an ecotoxicity biotest based on Escherichia coli for the sanitary control of water . The sensitivity of the proposed model was evaluated using a group of representative toxicants, and its response (synergism, additive or antagonism) to toxicants was observed . Finally, the biotest was applied to 124 water samples from rivers, underground sources, drinking water and wastewater . The results of the biotest were compared with the sanitary classification of the waters.

Appl Biochem Biotechnol, 1990 Oct, 26(1), 85 - 105
Algal biotechnology; Cannell RJ; The review gives a general outline of macro- and microalgal biotechnology . The main methods by which algae are cultivated and harvested are described . The first section deals with the environmental factors affecting mass culture and the principles governing the design and operation of mass cultivation systems . The second section gives the main current and potential uses of algae: in wastewater treatment, a source of food and feed, an energy source, and in the production of common and fine chemicals, such as polysaccharides, lipids, glycerol, pigments, and enzymes . Pharmaceutical uses of algae are described, and their potential as a source of novel biologically-active compounds is discussed . Future developments and the great potential of algae are considered.

Can J Microbiol, 1990 Sep, 36(9), 664 - 9
Detection and identification of poliovirus in environmental samples using nucleic acid hybridization; Preston DR et al.; A procedure was developed to effectively extract viral RNA from poliovirus tissue-culture lysates while eliminating the hybridization background associated with tissue cultures uninfected with poliovirus . Poliovirus cDNA cloned into a pUC vector was used as probe . Both the recombinant plasmids and the cDNA showed great specificity towards poliovirus . However, both probes hybridized with the single-stranded DNA coliphage phi X174 . Tissue culture was found to be an effective method to increase the number of viruses found in environmental samples to a level detectable by hybridization procedures, whereas direct hybridization of RNA from unamplified and highly concentrated raw wastewater showed poor hybridization signals . The specificity and sensitivity of the hybridization procedure developed during these studies indicate that this method may be best suited for the identification rather than the detection of viruses isolated from environmental samples.

J Toxicol Environ Health, 1990 Aug, 30(4), 305 - 21
Comprehensive Health Effects Testing Program for Denver's Potable Water Reuse Demonstration Project; Lauer WC et al.; The Comprehensive Health Effects Testing Program for the Denver Water Department's Potable Water Reuse Demonstration Project is designed to evaluate the relative health effects of highly treated reclaimed water derived from secondary wastewater compared to Denver's present high-quality drinking water . The 1 million gallon per day (1 mgd) demonstration plant provides water to be evaluated in the studies treating unchlorinated secondary treated wastewater with the following additional processes: high pH lime clarification, recarbonation, filtration, ultraviolet irradiation, activated carbon adsorption, reverse osmosis, air stripping, ozonation, and chloramination . An additional sample is obtained from the identical treatment process substituting ultrafiltration for reverse osmosis . The toxicology tests to evaluate the possible long-term health effects are chronic toxicity and oncogenicity studies in Fischer 344 rats and B6C3F1 mice and reproductive/teratology in Sprague-Dawley rats . The results of these evaluations will be correlated with microbiological, chemical, and physical test results to establish the relative quality of reclaimed water compared to all established health standards as well as Denver's pristine drinking water.

J Am Mosq Control Assoc, 1990 Jun, 6(2), 223 - 8
Mosquito control in wastewater: a controlled and quantitative comparison of pupfish (Cyprinodon nevadensis amargosae), mosquitofish (Gambusia affinis) and guppies (Poecilia reticulata) in Sago pondweed marshes; Castleberry DT et al.; We compared the abilities of pupfish, mosquitofish and guppies to control mosquitoes in wastewater marshes . All species of fish reduced mosquito emergence . When fish population densities were similar, fish reduced emergence to similar levels . As experiments progressed, guppies developed greater population densities and provided better mosquito control than mosquitofish, which developed greater densities and better control than pupfish . Fish also reduced numbers of zooplankton, and guppies increased total plant biomass, suggesting fish may influence the ability of wastewater marshes to treat wastewater.

Berl Munch Tierarztl Wochenschr, 1990 May 1, 103(5), 158 - 66
{Regional and recent trends in the chlorinated hydrocarbon levels in eels from Berlin waters}; Boiselle C et al.; During the five year period from early 1982 to 1986, we engaged in research concerning the chlorinated hydrocarbon content of eels (Anguilla anguilla L.) in the limnic water ecosystem of Berlin (West) . The total count of analytical samples, taken at 11 different sampling points, comprised 370 samples, divided up into 41 collectives . Each fish was checked individually for the patterns of contamination with chlorinated hydrocarbons, especially DDT-, BHC-, and PCB-related compounds . The various areas of the Berlin water system develop different particularities as regards pollution . The northern part, consisting mainly of the Tegeler See and the Niederneuendorfer See above the Spree river junction, is in near-neutral condition as shown by rather low levels of chlorinated hydrocarbons in the eels . The Teltowkanal, as it is heavily affected by industrial and urban wastewater, shows considerable contamination of its fish population . Main pollutants are the BHC-isomers, including delta-BHC and the DDT-metabolites 4.4-DDD and 4.4-DDE, as well as higher and lower chlorinated biphenyls (PCB) . The lower part of the Havel river, a lake system represented in this study by the fishing stations Stossensee, Pichelsdorfer Gemund, Schwanenwerder and Pfaueninsel, is limnologically a changing zone characterized by the influx of Spree and Havel rivers and in part by the Teltowkanal, which is reflected in the composition of the organochlorine contamination as well . Three main fishing stations were chosen to represent typical conditions of the ecosystem (Niederneuendorfer See, Pfaueninsel, Teltowkanal) and the trends of concentration of organochlorines in eels were monitored.(ABSTRACT TRUNCATED AT 250 WORDS)

Appl Environ Microbiol, 1990 May, 56(5), 1286 - 9
Effects of betaine on enumeration of airborne bacteria; Marthi B et al.; The osmoprotectant betaine was incorporated into collection fluid and enumeration medium to determine its effects on the colony-forming abilities of airborne bacteria, which were collected from three separate locations: a wastewater treatment plant, the roof of a laboratory building, and an unobstructed farmland . At all locations, addition of 2 to 5 mM betaine caused a significant increase (from 21.6 to 61.3%) in colonial outgrowth, compared with the growth rate of controls without betaine . The presence of betaine in both the collection fluid and the enumeration medium had an additive effect on the colony-forming ability of airborne bacteria compared with the presence of betaine in either one alone . The effect of various betaine concentrations on the enumeration of aerosolized Pseudomonas syringae was determined . Betaine showed a threshold for maximum effect at a concentration of 2 to 5 mM . At higher concentrations (10 to 20 mM), the effects of betaine were negligible or possibly inhibitory . The significance of these results with respect to the development of protocols for monitoring airborne microorganisms, including genetically engineered microorganisms, is discussed.

J Am Mosq Control Assoc, 1990 Mar, 6(1), 89 - 92
Efficacy of a juvenile hormone mimic, pyriproxyfen (S-31183), for mosquito control in dairy wastewater lagoons; Mulligan FS 3rd et al.; Pyriproxyfen (S-31183) was applied to dairy wastewater lagoons, during 1988, at 0.1 kg (AI)/ha in single and multiple applications which resulted in control of Culex spp . larvae for periods of 7 to 68 days . Length of the control period appeared to be related to water quality, with greater residual efficacy in more polluted sources . The AI apparently adsorbed onto organic debris where efficacy remained high in the lagoon even after water was pumped from the lagoon and replenished with untreated wastewater . Alternating treatments with control agents having a different mode of action is suggested to avoid selection of insecticide resistance.

ISA Trans, 1990, 29(2), 47 - 56
Structured approach in PLC (programmable logic controller) programming for water/wastewater applications; Keskar PY; This paper describes a methodology for efficient implementation of PLC programming for water/wastewater applications . The PLC was interfaced with a supervisory host computer which used touch screen equipped color monitors as operator interfaces . PLC ladder logic had to be designed to process real-world hardwired I/O as well as the I/O received from the host computer and/or touch screens, via a communications link . Standard "templates" of PLC networks were developed for (a) pump controls including provision for touch screen I/O; (b) PID control; (c) alarms; (d) motor run times; (e) square root extraction; (f) signal conversion, and (g) flow totalization . All logic was implemented using the standard templates . This structured approach led to efficient implementation, easy debugging/start-up, and easy to read uniform ladder logic.

Appl Environ Microbiol, 1990 Jan, 56(1), 295 - 7
Enhancement of enterovirus infectivity in vitro by pretreating host cell monolayers with the cationic polymer polyethyleneimine; Preston DR et al.; Laboratory strains of enteroviruses, as well as viruses isolated from raw wastewater, were found to exhibit enhanced infectivity in vitro when BGM cell monolayers were pretreated with the cationic polymer polyethyleneimine (PEI) . Viruses were assayed by the cytopathic effect technique and as PFU under methylcellulose and agar overlays with monolayers treated with 0 to 5.0 x 10(-3)% (wt/vol) PEI in phosphate-buffered saline supplemented with 2% fetal bovine serum . Poliovirus type 1 cytopathic effect occurred at an enhanced rate in cells treated with 5.0 x 10(-3)% PEI compared with untreated cells . PEI-treated cells were found to adsorb viruses much more effectively than untreated cells did . When the methylcellulose overlay procedure was used, rates of infectivity were enhanced as follows: poliovirus type 1, 5.5-fold; echovirus type 1, 1.2-fold; echovirus type 5, 5.2-fold; and coxsackievirus type B5, 4.9-fold . Viruses concentrated from raw wastewater showed a 3.8-fold increase in titer when quantitated by the most-probable-number method and a 3.3-fold increase when quantitated as PFU under an agar overlay.

J Med Virol, 1990 Jan, 30(1), 68 - 72
Antibodies to polioviruses in an Israeli population and overseas volunteers; Margalith M et al.; A seroepidemiological survey of prevalence of antibodies to poliovirus types 1-3 was carried out in 1,800 residents of 30 agricultural settlements (kibbutzim) in Israel during 1980 and 1981 . The survey showed that in 1980 84%, 90%, and 79% of the kibbutz residents exhibited antibodies to poliovirus types 1-3, respectively . In 1981 the figures were 81%, 91%, and 73% . Significantly lower levels of antibodies for poliovirus type 3 in 1980/1981, and for poliovirus type 1 in 1981, were noticed in the age group 6-17 years compared with the age group of greater than 18 years . Infants and young children of the kibbutzim received the Salk polio vaccine during 1957-1961 and the Sabin oral polio vaccine since 1961 . Among overseas volunteers from Western countries who came during 1980 and 1981 to work in the kibbutzim for a limited period of time, 88% exhibited antibodies to poliovirus type 1, 94% to poliovirus type 2, and 75% to poliovirus type 3 . No significant differences in the level of antibodies were detected between males and females or between residents in those kibbutzim using or not using wastewater for irrigation.

Comp Biochem Physiol C, 1990, 97(2), 381 - 5
Effects of domestic wastewater on serum enzyme activities of brown trout (Salmo trutta); Bucher F et al.; 1 . Chronic injuries of kidney and liver tissue of brown trout caused by domestic wastewater were not accompanied by increased activities of serum enzymes (GOT, GPT) . 2 . Increased enzyme activities were only observed in fish with acute Saproloegnia infection . 3 . It is important to distinguish between acute and chronic responses of serum enzymes in diseased fish.

Biodegradation, 1990, 1(4), 221 - 8
Biological decomposition of dichloromethane from a chemical process effluent; Stucki G; The application of specialized microorganisms to treat dichloromethane (DM) containing process effluents was studied . An aerobic fluidized bed reactor with a working volume of 801 filled with sand particles as carriers for the bacteria was used . Oxygen was introduced into the recycle stream by an injector device . DM was monitored semi-continuously . A processor controlled the feed volume according to the DM effluent concentration . Mineralization rates of 12 kg DM/m3bioreactor.d were reached within about three weeks using synthetic wastewater containing 2000 mg/l DM as single carbon compound . DM from process water of a pharmaceutical plant was reduced from about 2000 mg/l in the feed to below 1 mg/l in the effluent at volumetric loading rates of 3 to 4 kg DM/m3bioreactor.d . Degradation of wastewater components like acetone and isopropanol were favoured, thus making the process less attractive for waste streams containing high amounts of DOC other than of DM . DM concentrations of up to 1000 mg/l were tolerated by the immobilized microorganisms and did not influence their DM degradation capacity . The ability to mineralize DM was lost when no DM was fed to the reactor for 10 days.

J Chem Technol Biotechnol, 1990, 47(3), 219 - 33
Landfill co-disposal of phenol-bearing wastewaters: organic load considerations; Watson-Craik IA et al.; A multi-stage model, operated with single elution, was used to investigate the effects of organic loadings on the attenuation of a model phenolic wastewater in domestic refuse . Although 100% dissimilation of influent phenol (2-5 mmol dm-3) was recorded at a dilution rate of 0.007 h-1, partial inhibition of both phenol degradation and species competing with methanogens for a common electron donor(s) was apparent at concentrations greater than or equal to 4 mmol dm-3 . On extended perfusion with 8 mmol phenol dm-3, the progressive inhibition of phenol dissimilation was not obviated by nutrient supplementation . Simultaneous degradation of the catabolic intermediate, hexanoic acid, and elevated methane release rates suggested that the transformation of phenol to hexanoate was rate limiting.

Am J Public Health, 1989 Dec, 79(12), 1659 - 60
Gastrointestinal effects of water reuse for public park irrigation; Durand R et al.; To investigate the gastrointestinal effects of employing recycled water as an irrigation source for urban public parks, we studied subjects active in parks irrigated with potable water, nonpotable water of wastewater origin, and nonpotable water of runoff origin . Wet grass conditions during activity and elevated densities of common indicator bacteria, but not exposure to nonpotable irrigation water per se, were found associated with an increased rate of gastrointestinal illness.

Appl Environ Microbiol, 1989 Dec, 55(12), 3189 - 96
Evaluation of immunofluorescence techniques for detection of Cryptosporidium oocysts and Giardia cysts from environmental samples; Rose JB et al.; Cryptosporidium and Giardia species are enteric protozoa which cause waterborne disease . The detection of these organisms in water relies on the detection of the oocyst and cyst forms or stages . Monoclonal and polyclonal antibodies were compared for their abilities to react with Giardia cysts and Cryptosporidium oocysts after storage in water, 3.7% formaldehyde, and 2.5% potassium dichromate, upon exposure to bleach, and in environmental samples . Three monoclonal antibodies to Cryptosporidium parvum were evaluated . Each test resulted in an equivalent detection of the oocysts after storage, after exposure to bleach, and in environmental samples . Oocyst levels declined slightly after 20 to 22 weeks of storage in water, and oocyst fluorescence and morphology were dull and atypical . Oocyst counts decreased after exposure to 2,500 mg of sodium hypochlorite per liter, and fluorescence and phase-contrast counts were similar . Sediment due to algae and clays found in environmental samples interfered with the detection of oocysts on membrane filters . Two monoclonal antibodies and a polyclonal antibody directed against Giardia lamblia cysts were evaluated . From the same seeded preparations, significantly greater counts were obtained with the polyclonal antibody . Of the two monoclonal antibodies, one resulted in significantly lower cyst counts . In preliminary studies, the differences between antibodies were not apparent when used on the environmental wastewater samples . After 20 to 22 weeks in water, cyst levels declined significantly by 67% . Cysts were not detected with monoclonal antibodies after exposure to approximately 5,000 mg of sodium hypochlorite per liter.

Ecotoxicol Environ Saf, 1989 Dec, 18(3), 321 - 36
Ecotoxicological characterization of industrial wastewater--sulfite pulp mill with bleaching; Kallqvist T et al.; Different process wastewaters from a sulfite pulp mill with bleaching were characterized by chemical analysis and toxicity tests . The amount of adsorbable organically bound halogen (AOX) from the bleachery was 3.6 kg per ton pulp . The extractable organically bound chlorine was 15% of AOX . Some identified organochlorine compounds in the effluent could be traced in the receiving water . Effluents from the chlorination and alkaline extraction stages and the condensate were the main contributors to the effluent toxicity . The effluents were particularly toxic to the alga Skeletonema costatum . The EC50 value for growth of the alga was 24-29 ml/liter of the total effluent . The toxicity cannot be ascribed to single chemical components in the effluents . Degradation of toxic components occurs after dilution of the effluents in the receiving water . The toxicity may be reduced to 30-50% of the initial toxicity within 1 week . Predictions of toxic effects in the receiving water, based on results of toxicity tests and estimated dilution, indicate that large areas are affected by the discharges . Som observations of the distribution of organisms in the receiving water indicate that predictions from the toxicity tests may be valid.

J Med Entomol, 1989 Nov, 26(6), 566 - 72
Response of Culicoides variipennis (Diptera: Ceratopogonidae) to water level fluctuations in experimental dairy wastewater ponds; Mullens BA et al.; Water levels were fluctuated in experimental dairy wastewater ponds in southern California to study the response of Culicoides variipennis (Coquillet) . Immatures consistently were found in surface mud at the water's edge in ponds where the water level was stable . In ponds where the water level was fluctuated, immatures did not relocate to the new, lower waterline when the water quickly receded 3 m in horizontal distance . Younger larvae apparently were stranded above the waterline and were killed by heat or desication, or both; pupae and late fourth instars emerged as adults at the old waterline . A larvae were recovered from fairly dry mud up to 19 d after the water level receded . Substantial oviposition occurred at the lower waterline following the water level decrease, and adults began to emerge 14-18 d later . Immatures relocated to the higher waterline 3 h to 2 d after a rise in water level . Densities of this species were slightly, but not significantly, reduced in the fluctuated ponds under this water management regime . Water level fluctuations at 1-wk intervals might be expected to reduce substantially C . variipennis production from these habitats.

J Med Entomol, 1989 Nov, 26(6), 559 - 65
A quantitative survey of Culicoides variipennis (Diptera: Ceratopogonidae) in dairy wastewater ponds in southern California; Mullens BA; Culicoides variipennis (Coquillett) larvae were sampled five times over a 10-wk period in late summer in each of 26 dairy wastewater ponds in western Riverside County, Calif . Slope, degree of cattle access, prevalence of visible manure solids, salinity, chemical oxygen demand, plankton volume, and whether the ponds were pumped for irrigation were determined concurrently . Larvae of C . variipennis were associated positively with plankton volume, degree of animal access, and salinity, and negatively with slope and the pumping of the ponds for irrigation . High densities of larvae were found in shoreline mud in shallow, "evaporation bed" type ponds that were not pumped (means = 106 larvae per 30 ml) . In contrast, pumped ponds were deeper, had steeper slopes, and supported lower densities of C . variipennis (means = 52 larvae per 30 ml) . The pumped ponds tended to hold water continuously (more stable in time), and to have lower phytoplankton volumes and lower values of chemical oxygen demand . Rapid water level fluctuations in the pumped ponds also may have reduced C . variipennis density.

Ecotoxicol Environ Saf, 1989 Oct, 18(2), 204 - 10
Comparison between two Microtox test procedures; Tarkpea M et al.; A comparison between the two Microtox test procedures, the standard test and the 100% test, has been made . In the standard Microtox bioassay, effluents can be tested up to a concentration of 45% . The 100% test method, however, has been developed for screening effluents with an EC50 value greater than 45% . The relationship between 5-min EC50 values according to the two methods has been studied with a two-way ANOVA analysis for 14 effluents or process waters and one unpurified municipal wastewater sample . All samples were tested twice with a 3-month interval . An F ratio of 15.46 (n = 56) showed that the test methods differed significantly at the 0.1% level . Nevertheless none of the samples had a drastically different EC50 value when tested by the two methods . Both the treatment of the bacteria and the calculation of the EC50 values, which also affect the width of the 95% fiducial limits, differ in the two procedures . The confidence intervals were found to be 10.4 times broader in the 100% tests than in the corresponding standard test . Although the methods differ from each other both in performance and in statistical comparison of the results, both of them could be useful as prescreening methods for determining toxicity to aquatic organisms.

Toxicol Ind Health, 1989 Oct, 5(5), 825 - 37
Evaluating comparative potencies: developing approaches to risk assessment of chemical mixtures; Schoeny RS et al.; The U.S . EPA must provide guidance as to health risk assessment of mixtures from a variety of sources such as wastewaters, hazardous waste sites and air particulates . One approach to risk assessment of mixtures is to add up risk assessments for individual components identified as part of the mixture, after considering the potential for interaction among those components . This provides an index of hazard potential but not a quantitative estimate . When data on mixture components are incomplete, but these components are isomers or congeners of a well-studied chemical, another technique--use of toxic equivalency factors--can be applied . This approach has been proposed for estimating risk associated with chlorinated dioxins and dibenzofurans . A third approach, that of relative or comparative potency, is based on the assumption that for similar but not necessarily definable complex mixtures, a measure of relative potency based on data from in vitro tests can be correlated in a constant fashion with relative potency from an in vivo bioassay . The degree of confidence in the appropriateness of a relative potency method rests upon the way potency is measured and the validity of underlying assumptions (the degree to which these assumptions can be tested) . One class of assumptions involves choice of the model or procedure for deriving the quantitative risk estimates . A second set of assumptions deals with mechanism of action, and whether such considerations add bias or, in fact, refine the relative potency judgment . The choice of short-term tests appropriate for use in establishing the potency relationships is also a factor to be considered . This paper presents examples of proposed uses of relative potency in risk assessment and outlines some areas for further study.

Ann Ig, 1989 Sep-Oct, 1(5), 1001 - 14
{Surveillance of health status in an agrarian environment: proposal for a method . 2 . Environmental data}; Villa P et al.; In this second note, the Authors consider the environment surrounding the farms to identify the agricultural practices affecting both the ecological bicycle and the health of the farm-hands . The risk factors in the farm are principally the use of agricultural chemicals (pesticides, fertilizers, nitroso-compounds, etc.) and quality of the irrigation and drinkable water . In the first phase of the survey a complete analysis of environment was carried out to: a . identify all sources of pollution such as industries, roads, etc . b . consider drinkable water supplies, wastewater disposal and hygienic conditions in houses . At the same time data were collected about the use of pesticides, fertilizers and other agricultural chemicals, the characteristics of irrigation water, the presence of animals, storehouses, garages, etc . In the second phase of the survey a quality analysis of drinkable and irrigation water was carried out; the presence of dangerous chemicals (amines, nitrosoamines, nitrites, nitrates) in the vegetable caused by agricultural practices was also verified . The results demonstrated a substantial good hygienic situation of the farms but a bad state of drinkable and irrigation waters . We have difficulty in finding out how much and how the pesticides were used; therefore it will be necessary to control these practices more carefully . The amount of nitrites and nitrates in vegetables was normal, while no amines and nitrosoamines were found . The results suggest that it will be necessary in the future both to estimate the pesticide residues on the vegetables and the amount of fertilizers in the soil, and to analyse the soil composition.

Am J Public Health, 1989 Jul, 79(7), 850 - 2
Transmission of enteric disease associated with wastewater irrigation: a prospective epidemiological study; Shuval HI et al.; We conducted a prospective epidemiological study of possible enteric disease transmission by aerosolized pathogens from sprinkler irrigation of partially treated wastewater in 20 kibbutzim (collective agricultural settlements) in Israel between March 1981 and February 1982 . Medical data were collected from the patients' files and daily logs of physicians and nurses at each kibbutz clinic (total population 10,231) . Episodes of enteric disease were similar in the kibbutzim most exposed to wastewater aerosols (11.6 per 100 person-year) and the kibbutzim not exposed to wastewater in any form (11.0 per 100 person-year) . No excess of enteric disease was seen among wastewater contact workers or their families as compared with the unexposed . No negative health effects were detected in this study which involved a large population, including many young children, exposed to treated wastewater aerosols generated at distances of 300-600 m.

Ecotoxicol Environ Saf, 1989 Jun, 17(3), 339 - 71
Safety assessment of boron in aquatic and terrestrial environments; Butterwick L et al.; Boron is a naturally occurring material and is used in industrial and domestic products . Its major release into the environment is through weathering processes and wastewater discharge . Boron is an essential nutrient for plants, but can above certain concentrations be toxic to aquatic and terrestrial organisms . This paper assesses the ecotoxicology and environmental safety of boron . It draws together the data for toxicological effects of boron and compares these with environmental concentrations of boron, measured in Europe and the U.S.A . Generally, environmental concentrations of boron found in surface water are below levels identified as toxic to aquatic organisms . Concentrations high enough to produce toxic effects in laboratory tests are found in areas where weathering of boron-rich formations and deposits occurs, such as in the southwestern United States . However, reproducing populations of the most sensitive species, rainbow trout, have been observed in surface waters in these regions, indicating no cause for concern . The prime concern for effects on terrestrial plants centers on the use of irrigation water with elevated levels of boron . At present, there is no evidence of widespread damage to crops resulting from this practice . In some areas, wastewater is used for irrigation and crops grown under these conditions are generally confined to those relatively insensitive to boron toxicity . Good irrigation practices will be necessary, however, in arid regions with high evapotranspiration rates and care will be needed when using wastewater, particularly in areas with naturally high boron levels . It is not anticipated that there will be any significant increase in the discharge of boron to the environment in the foreseeable future . The use of boron-containing products is expected to increase, but glass will remain the dominant market and the use of boron in detergents in Europe is expected to decrease due to the introduction of bleach activators and liquid detergents . There is a possibility that perborate may be used in detergents in the U.S.A.; however, the estimated increase in boron concentrations is likely to be environmentally insignificant.

Sci Total Environ, 1989 May 15, 80(2-3), 113 - 25
Effect of applications of sewage sludge on N, P, K, Ca, Mg and trace element contents of plant tissues; Couillard D et al.; A four-month study was conducted in a greenhouse with Larix laricina grown on sand and nursery soil . This culture was fertilized with anaerobically digested sludge at various rates and doses . No direct relationship could be established between the growth of seedlings and the quantities of sludge applied . Relationships were, however, established between the quantities of sludge applied and the elemental composition of the tissues . There was a significant, positive correlation between the growth of seedlings and the phosphorus and nitrogen content of their tissues . These elements originated from the wastewater sludge . Tissues had potassium deficiencies and an excess of calcium, magnesium and trace elements.

Zhonghua Yu Fang Yi Xue Za Zhi, 1989 May, 23(3), 143 - 6
{Cadmium exposure and health effects among residents in irrigation area with ore dressing wastewater}; Cai SW; About 0.05 mg Cd/L was found in the irrigation water contaminated by the wastewater discharged from the wolfram ore dressing plants, and about 1 mg Cd/kg was found in irrigated acid soil . The main sources of the cadmium intake by residents, living in pollution areas, were agricultural products . The average intake of cadmium was 366.7-381.9 micrograms/d, smokers 416.6 micrograms/d . Among residents, who have been exposed to cadmium for more than 25 years, cadmium absorption (CdU greater than or equal to 10 micrograms/g Cre) was 60% and early effect of target organ (CdU greater than or equal to 15 micrograms/g Cre and beta 2 -mU greater than or equal to 500 micrograms/g Cre) was 17% . Levels of CdU and CdB were beyond the critical value in the observation areas . The concentrations of CaU, beta 2-mU and NAGU were significantly higher among residents in observation areas compared with control areas . Owing to the combined cadmium effect the cases with fractional beta 2-m excretion greater than 0.10 were 46% in the observation areas, and it was much higher than that in control areas (20.3%) in a case-control study among residents who have been suffering from an original nephropathy with tubulo-interstitial abnormalities.

Wei Sheng Wu Xue Bao, 1989 Apr, 29(2), 145 - 8
{Observations of predominant methanogens on biomass from AF, ABR, and UASB reactors treating different wastewaters}; Yang XS et al.; The biomass taken from AF, ABR, and UASB digesters treating municipal wastewater, swine waste and molassese stillage wastewater, municipal and molassese stillage wastewater respectively, were observed by light, epifluorescence microscope and scanning electron microscope . The prevalent methanogens in these digesters were Methanothrix . Exception for ABR carried out to treat swine waste, Methanosarcina with three forms of aggregations, cysts, and granules were presented in other digesters . A suggestion can be made that reactors with packing materials, such as, anaerobic filters, anaerobic contact beds and two-phase methanation digesters can be used to accumulate Methanosarcina due to their morphological, mu max, and Ks characteristics, in order to increase the wastewater treatment efficiency further.

Appl Environ Microbiol, 1989 Feb, 55(2), 507 - 10
Comparison of the presence-absence and membrane filter techniques for coliform detection in small, nonchlorinated water distribution systems; Bancroft K et al.; The traditional membrane filter (American Public Health Association, Standard Methods for the Examination of Water and Wastewater, 16th ed., American Public Health Association, Washington, D.C., 1985) and presence-absence (P-A) (J . A . Clark, Can . J . Microbiol . 14:13-18, 1968) techniques for the detection of coliform bacteria were compared in a small nonchlorinated drinking water distribution system by using total positive samples and frequency-of-occurrence analyses . No significant differences (P less than 0.05) were found in detection of the presence of coliform bacteria or in changes in the frequency of occurrence with time . A reduction in P-A sample volume (to 50 ml) was not found to statistically affect the comparative results of traditional membrane filter and P-A tests.

Appl Environ Microbiol, 1989 Feb, 55(2), 401 - 5
Simple method for the detoxification of wastewater ultrafiltration concentrates for rotavirus assay by indirect immunofluorescence; Oragui JI et al.; A simple method for the detoxification of ultrafiltration concentrates of wastewaters for rotavirus assay by the indirect immunofluorescence technique has been developed . Polyacrylamide (Bio-Gel) or dextran (Sephadex G50) beads were mixed with concentrates (0.5 g/10 ml, wt/vol) of wastewaters seeded with simian rotavirus SA11 and allowed to stand for 2 h . The supernatant was decontaminated with antibiotics and then assayed for rotaviruses . Concentrates from raw sewage and treated effluents seeded with SA11 were used to infect MA104 or LLC MK2 cell lines . The concentrates, particularly those from raw sewage and anaerobic waste stabilization ponds, were very toxic to the tissue culture cells . These toxic effects were determined by the detachment and subsequent loss of cells after incubation with concentrates and assay medium for 24 h . They were either completely eliminated or were reduced by greater than 80% after treatment with beads.

Arch Microbiol, 1989, 151(5), 381 - 90
Methanocorpusculaceae fam . nov., represented by Methanocorpusculum parvum, Methanocorpusculum sinense spec . nov . and Methanocorpusculum bavaricum spec . nov; Zellner G et al.; Two new methanogenic bacteria, Methanocorpusculum sinense spec . nov . strain DSM 4274 from a pilot plant for treatment of distillery wastewater in Chengdu (Province Sichuan, China), and Methanocorpusculum bavaricum spec . nov . strain DSM 4179, from a wastewater pond of the sugar factory in Regensburg (Bavaria, FRG) are described . Methanocorpusculum strains are weakly motile and form irregularly coccoid cells, about 1 micron in diameter . The cell envelope consists of a cytoplasmic membrane and a S-layer, composed of hexagonally arranged glycoprotein subunits with molecular weights of 90,000 (Methanocorpusculum parvum), 92,000 (M . sinense), and 94,000 (M . bavaricum) . The center-to-center spacings are 14.3 nm, 15.8 nm and 16.0 nm, respectively . Optimal growth of strains is obtained in the mesophilic temperature range and at a pH around 7 . Methane is produced from H2/CO2, formate, 2-propanol/CO2 and 2-butanol/CO2 by M . parvum and M . bavaricum, whereas M . sinense can only utilize H2/CO2 and formate . Growth of M . sinense and M . bavaricum is dependent on the presence of clarified rumen fluid . The G + C content of the DNA of the three strains is ranging from 47.7-53.6 mol% as determined by different methods . A similar, but distinct polar lipid pattern indicates a close relationship between the three Methanocorpusculum species . The polyamine patterns of M . parvum, M . sinense and M . bavaricum are similar, but distinct from those of other methanogens and are characterized by a high concentration of the otherwise rare 1,3-diaminopropane . Quantitative comparison of the antigenic fingerprint of members of Methanocorpusculum revealed no antigenic relationship with any one of the reference methanogens tested . On the basis of the distant phylogenetic position of M . parvum and the data presented in this paper a new family, the Methanocorpusculaceae fam . nov., is defined.

Gig Sanit, 1989 Jan, (1), 16 - 9
{Occurrence in the environment and among the population of antibiotic-resistant strains of pathogenic Escherichia}; Grigor'eva LV et al.; When studying antibioticograms of 1303 strains of pathogenic Escherichia, the correlation of their resistance with the character and source of emanation, exciters' serogroups and antibiotics has been established . The strains isolated from the environment, primarily from food-staffs, wash-out, and wastewater have higher antibiotic resistance . No significant differences are noted in the number of resistance markers as to the source of pathogenic Escherichia . The following antibiotic range is established: streptomycin-chloramphenicol (chloromycetin)--neomycin sulfate-tetracyline-kanamycin-polymyxin-gentamycin, thus the least number of strains in characterized by gentamycin resistance.

Endeavour, 1989, 13(3), 135 - 40
Biological monitoring and our water resources; Gruber D; Biological monitoring is a means of assessing water quality, or the toxicity of chemicals, employing living organisms as the sensors . Relatively recent environmental regulations have led to the application of biomonitoring techniques by wastewater discharges and chemical manufacturers . Classical approaches to biomonitoring have included the acute bioassay which takes death as the end-point of the test . Recent developments include automated and real time biomonitors which utilize computer technologies for assessing changes in physiological or behavioural parameters to indicate the presence of toxics.

J Virol Methods, 1988 Dec, 22(2-3), 337 - 46
A comparison of recovery of virus from wastewaters by beef extract-Celite, ferric chloride, and filter concentration procedures; Dahling DR et al.; An improved concentration method using sample volumes as large as 1500 ml has been developed to monitor for viruses in wastewaters . Non-precipitating dry beef extract powder is added to wastewater samples to give a 3% concentration and mixed until dissolved . This is followed by the addition of Celite as a virus adsorbent . By manipulating pH, viruses are eluted from the Celite in small volumes of phosphate buffer . This procedure was further tested without the aid of the Celite additives using a precipitating beef extract powder and substituting FeCl3 as an alternate reagent for the Celite . Comparison testing was also made with the currently recommended cartridge and disc filter procedures . In all cases, the non-precipitating beef extract-Celite method gave higher recovery rates in highly polluted waters.

J Appl Bacteriol, 1988 Nov, 65(5), 377 - 86
The use of bacteriophage as tracers of aerosols liberated by sludge suction appliances; Wheeler D et al.; Three bacteriophage tracers were added to 600-1 containers of water and simulated latrine sludge to provide high titres of tracer in aqueous and semi-aqueous media . After a period of mixing and stabilization, media were removed from the containers with suction hoses coupled to the vacuum pump of one of two sludge suction tankers . Exhaust air from the appliances was sampled by cyclone sampler and assayed for the presence of tracer organisms carried over during the emptying process . In the experiments the appliances were operated at different vacuum pump speeds, drawing both aqueous and semi-aqueous (simulated sludge) media . Air around one tanker was also sampled during the emptying, under pressure, of the vacuum vessel . The degree of aerosolization and expulsion of tracer bacteriophage by the vacuum appliances was consistently low, regardless of medium and pump air flow . In contrast, the proportion of tracer retained within the appliances was very high, exceeding the proportion expelled by a minimum of 8 log10 orders of magnitude and a maximum of greater than 11 log10 orders . The highest total of tracer bacteriophage was recovered during the pressure emptying of the vacuum vessel of one tanker . The results may be used for assessing and comparing potential public health hazards associated with the handling of wastewater sludge by vacuum appliances.

J Am Mosq Control Assoc, 1988 Sep, 4(3), 322 - 5
Efficacy of new insect growth regulators against mosquito larvae in dairy wastewater lagoons; Mulla MS et al.; Four new insect growth regulators (IGRs) and a slow-release formulation of a currently-used IGR were evaluated for the control of Culex peus and Cx . quinquefasciatus in dairy wastewater lagoons . The IGR AC-291898 (CME 13406) proved highly efficacious, producing 100% control for one week and about 98% control for two weeks at the rate of 0.05 lb AI/acre (0.056 kg/ha) . The IGR XRD-473 produced similar results at this rate . The effective rate of these two compounds seems to be in the range of 0.05 to 0.1 lb AI/acre (0.056-0.11 kg/ha) . A granular formulation of S-31183 (0.5 G) applied at 0.05 lb AI/acre (0.056 kg/ha) yielded mediocre reduction whereas fenoxycarb EC 1 at up to 0.25 lb AI/acre (0.28 kg/ha) and methoprene 4% slow release pellets at up to 1.0 lb AI/acre (1.12 kg/ha) produced little or no control of Culex in the dairy wastewater lagoons . These compounds need to be applied at higher rates or suitable formulations will have to be developed to achieve satisfactory control.

Biomed Environ Sci, 1988 Aug, 1(2), 210 - 21
Prediction of the environmental hazard of organic pollutants in an effluent from a pesticide-producing plant; Lindgaard-Jorgensen P; A prediction of the environmental hazard of 59 organic pollutants (e.g., pesticides, solvents, phenolics, and detergents) in the effluent from a pesticide-producing plant has been performed . Data on chemical fate (degradation, hydrolysis, volatilization, and bioaccumulation) and toxic effects have been obtained in a literature search and stored in a databank . The hazard has been evaluated on the basis of persistence, toxicity, and tendency to bioaccumulate . The predicted hazard, which indicates which pesticides are the most hazardous, is presented and visualized in plots of data from the databank on discharged amounts, persistence (in terms of half-lives), toxic effect concentrations related to the concentrations detected in the wastewater, and bioaccumulation factors (BCF).

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