Water Sci Technol, 2003, 48(5), 143 - 8 Horizontal sub-surface flow constructed wetland with pulsing water level; Vymazal J et al.; A constructed wetland with horizontal sub-surface flow at Dolni Mesto (Czech Republic) was put into operation in 1999 and treats municipal wastewater from 522 PE . The total area of vegetated beds of 2,646 m2 is divided into two parallel sections of equal size, each with two beds in series . Between two periods of water discharge there is no outflow from the bed . During the period of September 1999-September 2000 one bed was operated with a pulsing water level while the other one was not pulsing, i.e., was operated as regular sub-surface flow in order to evaluate the effect of pulsing on treatment efficiency, especially on removal of NH4-N . Between September 1999 and February 2000 the pulse was 8 cm, for the rest of the experimental period the pulse was 15 cm . The results indicate a positive effect of pulsing on removal of BOD5 (annual average of 53%), COD (30%) and NH4-N (27%) as compared to non-pulsing beds . For SS, a decrease in removal effect by 30% was observed . This is probably due to the higher outflow velocity of discharged water from pulsing beds which can flush out settled particles . The results also indicate that a pulsing level of 15 cm was more efficient than 8 cm. Water Sci Technol, 2003, 48(5), 93 - 100 Phosphorus sorption characteristics of a light-weight aggregate; Zhu T et al.; A light-weight aggregate (LWA) made of expanded clay used as a filter media in wastewater treatment, was tested for sorption of phosphorus (P) in laboratory experiments . The objectives were to investigate the different P retention pools and how grain size, time, temperature and changed P concentration influenced the P binding mechanisms in this type of filter . Three different grain sizes (0-2 mm, 2-4 mm and 0-4 mm) were tested in a batch experiment . The isotherm for the P sorbed by the contact medium (including retention and fixation) was obtained under laboratory conditions . Fifty percent of the P sorption occurred in the first 4-8 hours . Temperature did not substantially influence P sorption for 0-2 mm grain size LWA . In the LWA suspension system, P desorption did not occur when the P content in the loading solution decreased . Fractionation analysis indicated that Ca-bound P, loosely-bound P, and Al-bound P were the predominant P retention pools . The loosely-bound P pool was determined primarily by the equilibrated P concentration in the system . Fe-bound P was negligible in the P sorption of LWA. Water Sci Technol, 2003, 48(5), 85 - 92 Pumice soil: a potential wetland substrate for treatment of domestic wastewater; Njau KN et al.; Laboratory and fieldwork studies were carried out to evaluate the potential of pumice soil for use as a wetland substrate in wastewater treatment . The composition of pumice soil was analysed by x-ray fluorescence (XRF) and x-ray diffraction (XRD) techniques . Adsorption kinetic studies were carried out in a semi-batch recycle system . Fieldwork tests were carried out on Subsurface Flow Constructed Wetland (SSFCW) cells planted with Phragmites mauritianus and Vetiveria zizanioides . The results have shown that pumice soil composition contains among other elements Al, Ca, Fe and Mg, which are positive indicators for phosphorus adsorption . The main minerals observed by XRD were augite, hematite, and sodium titanium silicate . Phosphorus adsorption kinetics have shown that phosphorus is adsorbed on pumice soil following first order kinetics and the adsorption was highly influenced by mass transfer . Approximately 3% of the phosphorus was removed by plant uptake. Water Sci Technol, 2003, 48(5), 75 - 83 Phosphorus retention in subsurface constructed wetlands: investigations focused on calcareous materials and their chemical reactions; Molle P et al.; Phosphorus removal from wastewater has been of growing interest for some decades to avoid eutrophication in surface water . In subsurface constructed wetlands precipitation and adsorption are the main mechanisms responsible for P uptake . Two media (calcite and recycled crushed concrete (RCC)) were examined in batch and continuous systems . Batch experiments show attractive sorption capacities, however experiments carried out in open reactors pointed out some limitation in retention capacities and effluent quality . RCC is sensitive to a strong dissolution leading to a quick phosphorus precipitation but induces high conductivity and pH values in the treated water . Calcite efficiency depends on the carbonate equilibrium of the solution . Microscopic observations of the calcite surface show crystal growth of phosphorus precipitate . Crystallisation seems to be the main P uptake once a material's surface is covered. Water Sci Technol, 2003, 48(5), 51 - 8 Phosphorus removal from municipal wastewater in an experimental two-stage vertical flow constructed wetland system equipped with a calcite filter; Arias CA et al.; Laboratory studies have indicated that calcite may be used in separate, exchangeable filter units in constructed wetland systems to remove phosphorus . Based on these studies we built a full-scale experimental constructed wetland with a calcite-based filter unit to study its performance, under real-life conditions . The system consists of a 2-m3 sedimentation tank and two vertical flow constructed wetlands . The system has three 0.09 m3 calcite filter-units to study phosphorus removal . The hydraulic loading rate varied between 1.7 and 6.2 m3/d . The residence time in filters ranged from 28 to 99 minutes . Overall the system removed 62 +/- 18% of phosphorus . The removal in the calcite filter was initially good, but after three months all P-filters were saturated . The calcite increased pH by approximately half a unit and released calcium . A total of about 2.2 kg P/m3 calcite was removed by the filter . The first-stage bed receiving effluent from the sedimentation tank consistently removed phosphorus, whereas the second bed sometimes released phosphorus . The first order area-based removal rate constant for total-P in the vertical bed averaged 0.24 +/- 0.20 m/d and was highly dependent on the loading rate . This shows that first order removal kinetics do not satisfactorily describe removal of phosphorus in vertical flow constructed wetland systems with unsaturated flow. Water Sci Technol, 2003, 48(5), 25 - 34 Evaluation of substrate clogging processes in vertical flow constructed wetlands; Langergraber G et al.; Substrate clogging is by far the biggest operational problem of vertical flow constructed wetlands . The term "substrate clogging" summarises several processes which lead to reduction of the infiltration capacity at the substrate surface . The lower infiltration rate causes a reduced oxygen supply and further leads to a rapid failure of the treatment performance . Reasons for substrate clogging include accumulation of suspended solids, surplus sludge production, chemical precipitation and deposition in the pores, growth of plant-rhizomes and roots, generation of gas and compaction of the clogging layer . However, it is not clear how much each process contributes to the clogging process . Detailed investigations were carried out at pilot-scale constructed wetlands (PSCWs) using a variety of methods: e.g . soil physical investigations, microbial methods, and various analysis methods of drinking water and wastewater . The paper shows the results of these investigations and presents an equation to calculate the theoretical clogging time. Environ Sci Technol, 2003 Nov 1, 37(21), 5021 - 6 High-performance Ti/BDD electrodes for pollutant oxidation; Chen X et al.; Deposition of stable boron-doped diamond (BDD) films on Ti substrates is believed to be very difficult . In the present study, the stability of Ti/BDD electrodes has been significantly improved by using an organic additive, CH2(OCH3)2 . The improved electrodes had service lives of 175-264 h under accelerated life test conditions, which are 2.3-3.0 times longer than the service lives of electrodes prepared with the conventional H2 + CH4 mixture . Raman spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (SEM) examinations demonstrated thatthe films had well-defined diamond features . The current efficiency (CE) obtained on Ti/BDD was 46.9-78.5% in oxidizing acetic acid, maleic acid, phenol, and dyes, which is 1.6-4.3-fold higher than that obtained on the typical Ti/ Sb2O5-SnO2 electrode . We used a Ti/BDD electrode prepared with H2 + CH4 + CH2(OCH3)2 for over 300 h; its activity remained superior . The successful development of stable and active Ti/BDD electrodes significantly increases the feasibility of industrial applications of anodic oxidation in wastewater treatment. J Ind Microbiol Biotechnol, 2003 Nov, 30(11), 656 - 60 Epub 2003 Nov 11. Nitrate and phosphate removal by Spirulina platensis; Lodi A et al.; The cyanobacterium Spirulina platensis was used to verify the possibility of employing microalgal biomass to reduce the contents of nitrate and phosphate in wastewaters . Batch tests were carried out in 0.5 dm3 Erlenmeyer flasks under conditions of light limitation (40 micromol quanta m(-2) s(-1)) at a starting biomass level of 0.50 g/dm3 and varying temperature in the range 23-40 degrees C . In this way, the best temperature for the growth of this microalga (30 degrees C) was determined and the related thermodynamic parameters were estimated . All removed nitrate was used for biomass growth (biotic removal), whereas phosphate appeared to be removed mainly by chemical precipitation (abiotic removal) . The best results in terms of specific and volumetric growth rates (mu=0.044 day(-1), Qx=33.2 mg dm(-3) day(-1)) as well as volumetric rate and final yield of nitrogen removal (Q(N-NO3-)=3.26 mg dm(-3) day(-1), Y(N-NO3-)=0.739) were obtained at 30 degrees C, whereas phosphorus was more effectively removed at a lower temperature . In order to simulate full-scale studies, batch tests of nitrate and phosphate removal were also performed in 5.0 dm3 vessels (mini-ponds) at the optimum temperature (30 degrees C) but increasing the photon fluence rate to 80 micromol quanta m(-2) s(-1) and varying the initial biomass concentration from 0.25 to 0.86 g/dm3 . These additional tests demonstrated that an increase in the inoculum level up to 0.75 g/dm3 enhanced both NO3- and PO4(3-) removal, confirming a strict dependence of these processes on biomass activity . In addition, the larger surface area of the ponds and the higher light intensity improved removal yields and kinetics compared to the flasks, particularly concerning phosphorus removal (mu=0.032-0.050 day(-1), Qx=34.7-42.4 mg dm(-3) day(-1), Q(N-NO3-)=3.24-4.06 mg dm(-3) day(-1), Y(N-NO3-)=0.750-0.879, Q(P-PO4(3-))=0.312-0.623 mg dm(-3) day(-1), and Y(P-PO4(3-))=0.224-0.440). Environ Toxicol, 2003 Dec, 18(6), 413 - 7 Cavitation-induced pyrolysis of toxic chlorophenol by high-frequency ultrasonic irradiation; Hao H et al.; p-Chlorophenol (4-CP) is a recalcitrant organic pollutant that is biologically toxic in industrial wastewater . A high-frequency ultrasonic device operated at 1.7 MHz was designed and used successfully to degrade 4-CP . Iodine liberation in the KI aqueous solution confirmed that effective cavitation occurred under the high-frequency ultrasonic irradiation . No products or intermediate products were detected following the sonochemical degradation by 1H-nuclear magnetic resonance spectrum and mass spectrum after ultrasonic irradiation . It was concluded that the dominant degradation mechanism was high-temperature pyrolysis to inorganic products in ultrasonic cavities rather than free-radical oxidation . Environ Toxicol, 2003 Dec, 18(6), 395 - 402 A practical and user-friendly toxicity classification system with microbiotests for natural waters and wastewaters; Persoone G et al.; Various types of toxicity classification systems have been elaborated by scientists in different countries, with the aim of attributing a hazard score to polluted environments or toxic wastewaters or of ranking them in accordance with increasing levels of toxicity . All these systems are based on batteries of standard acute toxicity tests (several of them including chronic assays as well) and are therefore dependent on the culturing and maintenance of live stocks of test organisms . Most systems require performance of the bioassays on dilution series of the original samples, for subsequent calculation of L(E)C50 or threshold toxicity values . Given the complexity and costs of these toxicity measurements, they can only be applied in well-equipped and highly specialized laboratories, and none of the classification methods so far has found general acceptance at the international level . The development of microbiotests that are independent of continuous culturing of live organisms has stimulated international collaboration . Coordinated at Ghent University, Belgium, collaboration by research groups from 10 countries in central and eastern Europe resulted in an alternative toxicity classification system that was easier to apply and substantially more cost effective than any of the earlier methods . This new system was developed and applied in the framework of a cooperation agreement between the Flemish community in Belgium and central and eastern Europe . The toxicity classification system is based on a battery of (culture-independent) microbiotests and is particularly suited for routine monitoring . It indeed only requires testing on undiluted samples of natural waters or wastewaters discharged into the aquatic environment, except for wastewaters that demonstrate more than 50% effect . The scoring system ranks the waters or wastewaters in 5 classes of increasing hazard/toxicity, with calculation of a weight factor for the concerned hazard/toxicity class . The new classification system was applied during 2000 by the participating laboratories on samples of river water, groundwaters, drinking waters, mine waters, sediment pore waters, industrial effluents, soil leachates, and waste dump leachates and was found to be easy to apply and reliable . Bioresour Technol, 2004 Feb, 91(3), 249 - 57 Kinetic modeling and equilibrium studies during cadmium biosorption by dead Sargassum sp . biomass; Cruz CC et al.; A basic investigation on the removal of cadmium(II) ions from aqueous solutions by dead Sargassum sp . was conducted in batch conditions . The influence of different experimental parameters; initial pH, shaking rate, sorption time, temperature and initial concentrations of cadmium ions on cadmium uptake was evaluated . Results indicated that cadmium uptake could be described by the Langmuir adsorption model, being the monolayer capacity negatively affected with an increase in temperature . Analogously, the adsorption equilibrium constant decreased with increasing temperature . The kinetics of the adsorption process followed a second-order adsorption, with characteristic constants increasing with increasing temperature . Activation energy of biosorption could be calculated as equal to 10 kcal/mol . The biomass used proved to be suitable for removal of cadmium from dilute solutions . Its maximum uptake capacity was 120 mg/g . It can be considered an optimal result when compared to conventional adsorbing materials . Thus Sargassum sp . has great potential for removing cadmium ions especially when concentration of this metal is low in samples such as wastewater streams. J Microbiol Methods, 2003 Dec, 55(3), 859 - 64 Rains, drains and active strains: towards online assessment of wastewater bacterial communities; Forster S et al.; Wastewater treatment is one of the largest scale and arguably the most commercially important biotechnological process in the world . Bacterial breakdown of waste materials facilitates the safe disposal of effluents into receiving water bodies . Given this significance, research has focused on identifying the keystone species on which efficient treatment is based . However, unravelling the microbial diversity within such systems has proven difficult . This is highlighted by our lack of detailed knowledge of the microbial interactions within these complex populations, limiting our ability to fully exploit bacterial degradative abilities . Even with the incorporation of new emerging molecular techniques, there have been no investigations linking genetic sequence to microbial function and successful treatment operation . To reach this goal, researchers need the ability to identify, enumerate and monitor the metabolic functions of subpopulations within these complex bacterial communities . Flow cytometry (FCM) combined with fluorescence-based molecular identification techniques provides a method for such studies . Moreover, single-cell sorting provides a unique opportunity to identify and remove individual cells of interest . Laboratory culture of sorted cells is often possible and permits the use of more traditional microbiological techniques to backup molecular investigations . Utilising this approach will advance our understanding of wastewater treatment processes and help maintain and enhance plant operation to improve efficiency. Appl Microbiol Biotechnol, 2004 May, 64(4), 599 - 603 Epub 2003 Nov 05. Chromium and aluminum biosorption on Chryseomonas luteola TEM05; Ozdemir G et al.; Cr(VI) and Al(III) are environmental pollutants that are frequently encountered together in industrial wastewaters, e.g., from mining iron-steel, metal cleaning, plating, metal processing, automobile parts, and the manufacturing and dye industries . In this work, several variables that affect the capacity for chromium and aluminum biosorption by Chryseomonas luteola TEM05 were studied, particularly the effects of pH, metal concentration and contact time . Optimum adsorption pH values of Cr(VI) and Al(III) were determined as 4.0 and 5.0, respectively . The biosorption equilibrium was described by Freundlich and Langmuir adsorption isotherms . The value of Qo appears to be significantly higher for the Al(III) C . luteola TEM05 system . Langmuir parameters of C . luteola TEM05 also indicated a maximum adsorption capacity of 55.2 mg g(-1) for Al(III) and 3.0 mg g(-1) for Cr(VI) . J Clin Microbiol, 2003 Nov, 41(11), 5254 - 7 Molecular surveillance of Cryptosporidium spp . in raw wastewater in Milwaukee: implications for understanding outbreak occurrence and transmission dynamics; Zhou L et al.; Six Cryptosporidium spp . were found in 50 of 179 Milwaukee wastewater samples collected weekly over a year . Of the eight subtypes of Cryptosporidium hominis and Cryptosporidium parvum present, allele Ib was found in 14 of 16 samples, and its sequence was identical to that of the subtype in human samples from the 1993 Milwaukee outbreak of cryptosporidiosis. Water Res, 2003 Dec, 37(20), 4945 - 53 Adsorptive separation of arsenate and arsenite anions from aqueous medium by using orange waste; Ghimire KN et al.; Cellulose and orange waste were chemically modified by means of phosphorylation . The chemically modified gels were further loaded with iron(III) in order to create a suitable chelating environment for arsenate and arsenite removal . The loading capacity for iron(III) on the gel prepared from orange waste (POW) was 1.21 mmol g(-1) compared with 0.96 mmol g(-1) for the gel prepared from cellulose (PC) . Removal tests of arsenic with the iron(III)-loaded gel were carried out batchwise and by using a column . Arsenite removal was favored under alkaline condition for both PC and POW gels, however, the POW gel showed some removal capability even at neutral pH . On contrary, arsenate removal took place under acidic conditions at pH=2-3 and 2-6 for the PC and POW gels, respectively . Since iron(III) loading is higher on the POW gel than on the PC gel greater arsenic removal has been achieved by the POW gel compared with the PC gel . It can be concluded that the POW gel can be used for the removal and recovery of both arsenite and arsenate from arsenic contaminated wastewater. Water Res, 2003 Dec, 37(20), 4835 - 42 Modeling heavy metal uptake by sludge particulates in the presence of dissolved organic matter; Wang J et al.; The uptake of the seven heavy metal ions Cd(II), Co(II), Cr(III), Cu(II), Ni(II), Pb(II), and Zn(II) by sludge particulates in single-metal systems was investigated . Results showed that under acidic and neutral pH conditions, the uptake of all heavy metals by sludge particulates increases with the increase of pH . However, in the alkaline pH region, the uptake of Cu(II), Ni(II), and Co(II) decreases with the increase of pH, primarily due to the high dissolved organic matter (DOM) concentration in high pH conditions . Based on chemical reactions among heavy metal, sludge solids, and DOM, a mathematical model describing metal uptake as functions of DOM and pH was developed . The stability constants of metal-sludge and metal-DOM complexes can be determined using this model in conjunction with experimental metal uptake data . Results showed that, for the secondary sludge sample collected from Baltimore Back River Wastewater Treatment plant on March 1997, the stability constants of Cu(II)-sludge complex (log K(S)) and Cu(II)-DOM complex (log K(L)) are 5.3+/-0.2 and 4.7+/-0.3, respectively; for Ni(II), they are 4.0+/-0.2 and 3.9+/-0.2, respectively . Results also showed that under neutral and low pH conditions (pH<8), the DOM effects on metal uptake for all heavy metals are insignificant . Therefore, the DOM term in the model can be ignored . Results showed that, for the secondary sludge sample collected from Baltimore Back River Wastewater Treatment plant on December 1996, the estimated log K(S) values of metal-sludge complexes for Cd(II), Co(II), Cr(III), Cu(II), Ni(II), Pb(II), and Zn(II) are, respectively, 3.6+/-0.2, 3.0+/-0.1, 5.5+/-0.1, 4.8+/-0.1, 3.1+/-0.1, 5.1+/-0.1, and 4.4+/-0.3. Water Res, 2003 Dec, 37(20), 4823 - 34 Stabilized leachates: ozone-activated carbon treatment and kinetics; Rivas FJ et al.; Ozone has been used as a pre-oxidation step for the treatment of stabilized leachates . Given the refractory nature of this type of effluents, the conversion of some wastewater quality parameters has been moderate after 1 h of ozonation (i.e . 30% chemical oxygen demand (COD) depletion) . Ozone uptake was calculated in the interval 1.3-1.5 g of ozone per gram of COD degraded . An optimum dose of ozone has been experienced in terms of biodegradability of the processed effluent (60 min of treatment, 1 x 10(-3) mol L(-1) ozone inlet feeding concentration and 50 L h(-1) gas flow-rate) . pH and other typical hydroxyl radical generator systems exerted no influence on the efficiency of the process, suggesting the negligible role played by the indirect route of oxidation (generation of hydroxyl radicals) . The ozonated effluent was thereafter treated in a second adsorption stage by using a commercial activated carbon . Removal levels up to 90% of COD in approximately 120 h were experienced for adsorbent dosages of 30 g L(-1) . Both steps, the single ozonation and the adsorption stage have been modelled by using different pseudoempirical models. Chemosphere, 2004 Feb, 54(6), 695 - 705 A holistic passive integrative sampling approach for assessing the presence and potential impacts of waterborne environmental contaminants; Petty JD et al.; As an integral part of our continuing research in environmental quality assessment approaches, we have developed a variety of passive integrative sampling devices widely applicable for use in defining the presence and potential impacts of a broad array of contaminants . The semipermeable membrane device has gained widespread use for sampling hydrophobic chemicals from water and air, the polar organic chemical integrative sampler is applicable for sequestering waterborne hydrophilic organic chemicals, the stabilized liquid membrane device is used to integratively sample waterborne ionic metals, and the passive integrative mercury sampler is applicable for sampling vapor phase or dissolved neutral mercury species . This suite of integrative samplers forms the basis for a new passive sampling approach for assessing the presence and potential toxicological significance of a broad spectrum of environmental contaminants . In a proof-of-concept study, three of our four passive integrative samplers were used to assess the presence of a wide variety of contaminants in the waters of a constructed wetland, and to determine the effectiveness of the constructed wetland in removing contaminants . The wetland is used for final polishing of secondary-treatment municipal wastewater and the effluent is used as a source of water for a state wildlife area . Numerous contaminants, including organochlorine pesticides, polycyclic aromatic hydrocarbons, organophosphate pesticides, and pharmaceutical chemicals (e.g., ibuprofen, oxindole, etc.) were detected in the wastewater . Herein we summarize the results of the analysis of the field-deployed samplers and demonstrate the utility of this holistic approach. Environ Technol, 2003 Sep, 24(9), 1165 - 73 Thermal efficiency and environmental performances of a biogas-diesel stationary engine; Bilcan A et al.; Municipal and agricultural waste, and sludge from wastewater treatment represent a large source of pollution . Gaseous fuels can be produced from waste decomposition and then used to run internal combustion engines for power and heat generation . The present paper focuses on thermal efficiency and environmental performances of dual-fuel engines fuelled with biogas . Experiments have been carried out on a Lister-Petter single cylinder diesel engine, modified for dual-fuel operation . Natural gas was first used as the primary fuel . An empirical correlation was determined to predict the engine load for a given mass flow rate for the pilot fuel (diesel) and for the primary fuel (natural gas) . That correlation has then been tested for three synthesized biogas compositions . Computations were performed and the error was estimated to be less than 10% . Additionally, NOx and CO2 contents were measured from exhaust gases . Based on exhausts gas temperature, the activation energy and the pre-exponential factor of an Arrhenius law were then proposed, resulting in a simpler mean to predict NOx. Environ Technol, 2003 Sep, 24(9), 1135 - 45 Application of electrochemical process for landfill leachate treatment with emphasis on heavy metal and organic removal; Thaveemaitree Y et al.; This study was conducted to investigate the mechanisms of electrochemical treatment of a landfill leachate with emphasis on lead and organic removal . Laboratory electrochemical experiments were conducted using both synthetic wastewater and landfill leachate samples . From the synthetic wastewater experiments, the lead removal efficiencies were found to be more than 99% . The lead removal was observed to be dependent on: the electrical current, ratio between reacting surface area and volume of reactor and operation time, and following a first-order reaction . Similar results on lead removal were obtained when the landfill leachate samples were treated in the electrochemical reactor; the percent removal of soluble biological oxygen demand and soluble chemical oxygen demand concentrations from the landfill leachate during the electrochemical treatment were 30-60%, while the color removal was 70% . The sludge generated from the electrochemical reactions using the synthetic lead wastewater, analyzed by X-ray diffractometry, was found to be composed mainly of maghemite, magnetite, and laurionite . Based on the X-ray fluorescence spectrometry analysis, the percent contents of iron and lead were 68.6% as maghemite and 10.1% as lead oxide, respectively . The sludge generated from the landfill leachate treatment containing lead, analyzed by X-ray diffractometry, was found to be composed mainly of maghemite . Based on the X-ray fluorescence spectrometry analysis, the percent contents of iron and lead in the sludge were 69.49% as maghemite and 0.63% as lead oxide, respectively . The sludge volume index, capillary suction time and leachability values of the sludge were in suitable range for settling, dewatering and disposal. Bioresour Technol, 2004 Jan, 91(2), 207 - 14 Assessing the feasibility of achieving biological nutrient removal from wastewater at an Irish food processing factory; Mulkerrins D et al.; In Ireland, wastewaters emanating from the food industry typically contain elevated levels of nitrogen and phosphorus before treatment . Two pilot scale studies were performed to determine the feasibility of achieving biological N and P removal on-site at a food ingredients plant . The wastewater treated by the pilot reactors was that which resulted from the day-to-day production in the full-scale food ingredients plant . Both reactors were of the anaerobic/anoxic/oxic (A/A/O) design, however the sizing of the zones was varied in this study . In the first pilot study, while treating a wastewater of the following strength: 1008 mg COD/l; 30.1 mg NH4-N/l and 26.7 mg P/l, removal efficiencies of 93%, 99% and 98% were obtained for COD, NH4-N and P, respectively . In the second study, while operating at reduced hydraulic retention times and lower recycle rates, the pilot plant treated a wastewater of the following strength: 1757 mg COD/l; 62 mg NH4-N/l and 57 mg P/l, with removal efficiencies of 94%, 97% and 75% obtained for COD, NH4-N and P, respectively . This work showed that biological nutrient removal could be successfully applied to treatment of food industry wastewaters. Water Environ Res, 2003 Sep-Oct, 75(5), 412 - 21 Evaluation of constructed wetland treatment performance for winery wastewater; Grismer ME et al.; Rapid expansion of wineries in rural California during the past three decades has created contamination problems related to winery wastewater treatment and disposal; however, little information is available about performance of on-site treatment systems . Here, the project objective was to determine full-scale, subsurface-flow constructed wetland retention times and treatment performance through assessment of water quality by daily sampling of total dissolved solids, pH, total suspended solids, chemical oxygen demand (COD), tannins, nitrate, ammonium, total Kjeldahl nitrogen, phosphate, sulfate, and sulfide across operating systems for winery wastewater treatment . Measurements were conducted during both the fall crush season of heavy loading and the spring following bottling and racking operations at the winery . Simple decay model coefficients for these constituents as well as COD and tannin removal efficiencies from winery wastewater in bench-scale reactors are also determined . The bench-scale study used upward-flow, inoculated attached-growth (pea-gravel substrate) reactors fed synthetic winery wastewater . Inlet and outlet tracer studies for determination of actual retention times were essential to analyses of treatment performance from an operational subsurface-flow constructed wetland that had been overloaded due to failure to install a pretreatment system for suspended solids removal . Less intensive sampling conducted at a smaller operational winery wastewater constructed wetland that had used pretreatment suspended solids removal and aeration indicated that the constructed wetlands were capable of complete organic load removal from the winery wastewater. Environ Toxicol Chem, 2003 Nov, 22(11), 2622 - 9 Quantification of steroid hormones with pheromonal properties in municipal wastewater effluent; Kolodziej EP et al.; Many fish use steroid hormones as pheromones to initiate behavioral and physiological changes during spawning . To assess the occurrence of steroid hormones with pheromonal properties in the aquatic environment and to evaluate the possibility that municipal wastewater discharges contain compounds that could affect fish reproduction by interfering with pheromones, several estrogens, androgens, and progestins were quantified by gas chromatography/tandem mass spectroscopy in effluent samples from 12 municipal wastewater treatment plants . Samples also were analyzed from an engineered treatment wetland, three groundwater wells, and one reservoir . Estrogens (17beta-estradiol and estrone) were detected in wastewater effluent at maximum concentrations of 4 and 12 ng/L, respectively . Androgens (testosterone and androstenedione) were detected at concentrations as high as 6.1 and 4.5 ng/L, respectively, whereas the synthetic progestin medroxyprogesterone was detected at concentrations up to 15 ng/L . Data from an effluent-receiving engineered treatment wetland and shallow groundwater wells suggested that these compounds were not rapidly attenuated . The measured concentrations of steroids often exceeded olfactory detection thresholds at which fish detect these steroids, and in several cases, the steroid concentrations were comparable to levels at which pheromonal responses have been observed in fish. Biotechnol Lett, 2003 Oct, 25(19), 1657 - 9 Removal of low molecular weight phenols from olive oil mill wastewater using microalgae; Pinto G et al.; The treatment of olive oil mill wastewater (OMW) with two phenol resistant algae, Ankistrodesmus braunii and Scenedesmus quadricauda, showed a limited reduction of phenol content after 5 d of treatment, irrespective of algal concentration . Otherwise, cultures of both algae, grown in the dark, degraded over 50% of the low molecular weight phenols contained in OMW, but they were not completely removed, but were biotransformed into other non-identified, aromatic compounds. Waste Manag, 2003, 23(9), 817 - 24 Assessment and analysis of industrial liquid waste and sludge disposal at unlined landfill sites in arid climate; Al Yaqout AF; Municipal solid waste disposal sites in arid countries such as Kuwait receive various types of waste materials like sewage sludge, chemical waste and other debris . Large amounts of leachate are expected to be generated due to the improper disposal of industrial wastewater, sewage sludge and chemical wastes with municipal solid waste at landfill sites even though the rainwater is scarce . Almost 95% of all solid waste generated in Kuwait during the last 10 years was dumped in five unlined landfills . The sites accepting liquid waste consist of old sand quarries that do not follow any specific engineering guidelines . With the current practice, contamination of the ground water table is possible due to the close location of the water table beneath the bottom of the waste disposal sites . This study determined the percentage of industrial liquid waste and sludge of the total waste dumped at the landfill sites, analyzed the chemical characteristics of liquid waste stream and contaminated water at disposal sites, and finally evaluated the possible risk posed by the continuous dumping of such wastes at the unlined landfills . Statistical analysis has been performed on the disposal and characterization of industrial wastewater and sludge at five active landfill sites . The chemical analysis shows that all the industrial wastes and sludge have high concentrations of COD, suspended solids, and heavy metals . Results show that from 1993 to 2000, 5.14+/-1.13 million t of total wastes were disposed per year in all active landfill sites in Kuwait . The share of industrial liquid and sludge waste was 1.85+/-0.19 million t representing 37.22+/-6.85% of total waste disposed in all landfill sites . Such wastes contribute to landfill leachate which pollutes groundwater and may enter the food chain causing adverse health effects . Lined evaporation ponds are suggested as an economical and safe solution for industrial wastewater and sludge disposal in the arid climate of Kuwait. J Environ Manage, 2003 Nov, 69(3), 239 - 47 Water issues in comprehensive municipal planning: a review of the Motala River Basin; Gullstrand M et al.; The performance level for water management is rising in Sweden after the passing of a number of Governmental Bills (1997-2000) that establish national environmental quality objectives, and furthermore after the adoption of the Water Framework Directive of the European Union (2000) . The presentation of water issues in municipal physical planning is important because the municipalities have a local planning monopoly . We investigate to what extent water resources are considered in one of the most important tools for the regulation of physical infrastructure, namely the Comprehensive Municipal Plans . Thirteen plans from municipalities within the Motala River Basin in southern Sweden were studied . To characterise the comprehensiveness of the plans we used twelve criteria, divided into five groups: description, preventive measures, goal-setting, implementation strategy and future-oriented considerations . Descriptions of water quality, water use, wastewater plants, and urban water and wastewater systems were the most frequent items . These topics could be found in all plans in the study, along with more or less elaborated river basin perspectives . Issues related to national environmental quality objectives were mentioned in only five of the plans, and considerations about water flows were even more rare . We found, that the emphasis on water issues is not correlated with the size of the municipal population but rather with the age of the plans . In the old plans from the early 1990s water management is less recognised than in the newly revised ones . After their adoption the national water quality objectives, and suggested measures to fulfil them, are being translated into regional and local levels, and this has happened in the new plans . However, it seems that water has not yet gained the same importance as land in municipal physical planning, and strategies for public participation in the planning process are lacking. J Environ Manage, 2003 Nov, 69(3), 229 - 38 The removal of dyes from textile wastewater: a study of the physical characteristics and adsorption mechanisms of diatomaceous earth; Al-Ghouti MA et al.; The feasibility of using diatomite for the removal of the problematic reactive dyes as well as basic dyes from textile wastewater was investigated . Methylene blue, Cibacron reactive black and reactive yellow dyes were considered . Physical characteristics of diatomite such as pHsolution, pHZPC, surface area, Fourier transform infrared, and scanning electron microscopy were investigated . The surface area of diatomite was found to be 27.80 m2g(-1) and the pHZPC occurred around pH of 5.4 . The results indicated that the surface charge of diatomite decreased as the pH of the solution increased with the maximum methylene blue removal from aqueous solution occurring at basic pH of around (10-11) . Adsorption isotherms of diatomite with methylene blue, hydrolysed reactive black and yellow dyes were constructed at different pH values, initial dye concentrations and particle sizes . The experimental results were fitted to the Langmuir, Freundlich, and Henry models . The study indicated that electrostatic interactions play an important role in the adsorption of dyes onto diatomite . A model of the adsorption mechanism of methylene blue onto diatomite is proposed. Chemosphere, 2004 Jan, 54(3), 435 - 41 Color and COD removal from wastewater containing Reactive Black 5 using Fenton's oxidation process; Meric S et al.; In this study, Reactive Black 5 (RB5) was removed from synthetic wastewater using Fenton's oxidation (FO) process . Experiments were conducted on the samples containing 100 and 200 mg l(-1) of RB5 to remove the dye toxicity . Seventy-five milligram per litre of RB5 caused 25% toxicity on 24-h born daphnids whereas 100 mg l(-1) of RB5 displayed 100% toxicity on Daphnia magna . The study was performed in a systematic approach searching optimum values of FeSO(4) and H(2)O(2) concentrations, pH and temperature . Optimum pH and temperature for 100 mg l(-1) of RB5 were observed as 3.0 and 40 degrees C, respectively, using 100 mg l(-1) of FeSO(4) and 400 mg l(-1) of H(2)O(2) resulted in 71% chemical oxygen demand (COD) and 99% color removal . For 200 mg l(-1) of RB5, 84% COD removal was obtained using 225 mg l(-1) of FeSO(4) and 1000 mg l(-1) of H(2)O(2) yielding 0.05 molar ratio at pH 3.0 and 40 degrees C . Color removal was also more than 99% . The optimum conditions determined in accordance with the literature data . The H(2)O(2) requirement seems to be related to initial COD of the sample . FeSO(4)/H(2)O(2) ratios found were not changed for both concentrations . The temperature affected the COD removal significantly at high degrees . Toxicity was completely removed for each concentration of RB5 at optimum removal conditions. Chemosphere, 2004 Jan, 54(3), 413 - 7 Recovery of astaxanthin from seafood wastewater utilizing fish scales waste; Stepnowski P et al.; The paper presents basic data on astaxanthin adsorption from fisheries wastewater to fish scales . This process has been proposed to be applicable in fisheries and shrimp waste management {Helgason, Recovery of compounds using a natural adsorbent, Patent WO 01/77230, 2001} . The innovative feature of the method is the application of a solid waste (fish scales) as a natural adsorbent for a carotenoid pigment (astaxanthin) from the seafood industry wastewater . The model investigations were performed with pure synthetic carotenoids to exclude the role of matrix in which astaxanthin is present in the wastewater . Under the experimental conditions used, the maximum loading capacity of astaxanthin onto the scales is 360 mg kg(-1) dry wt . Studies of the thus formed value added product indicated that drying causes significant loss of astaxanthin activity . Due to the effective filtration characteristics of the studied sorption material, we suggest the scale/astaxanthin sorption process to be suitable for treatment of wastewater from different industries. Chemosphere, 2004 Jan, 54(3), 325 - 33 Removal of cyanide by woody plants; Larsen M et al.; Hydrogen cyanide is a high volume production chemical that causes severe environmental problems . The toxicity of potassium cyanide (KCN) to basket willow trees (Salix viminalis) was tested . In aqueous solution, 2 mg CN l(-1) as KCN depressed the transpiration after 72 h about 50% . Trees exposed to 0.4 mg CN l(-1) in aqueous solution showed initially a depression of transpiration, but recovered . Doses of 8 and 20 mg CN l(-1) in aqueous solution were quickly mortal to the trees . At the end of the test, almost all cyanide had disappeared from the solutions . Levels of cyanide in plants were related to the toxicity, with no elevated levels of cyanide in plants exposed to 0.4 mg CN l(-1) . Willows grown in sand survived 423.5 h irrigation with 20 mg CN l(-1) . Willows grown in sand irrigated with 50 mg CN l(-1) died within a few days . The roots of the surviving willows were able to consume about 10 mg CN kg fresh weight(-1)h(-1) . Vascular plants possess the enzymes beta-cyanoalanine synthase and beta-cyanoalanine hydrolase, which convert free cyanide to the amino acid asparagine . The in vivo capacity of woody plants (willow, poplar, elder, rose, birch) to remove cyanide was evaluated . Tests were performed with detached leaves and roots in KCN solutions of different concentrations . The highest removal capacity was obtained for basket willow hybrids (Salix viminalis x schwerinii) . The Michaelis-Menten kinetics was determined . Realistic values of the half-saturation constant, K(M), were between 0.6 and 1.7 mg CN l(-1); the maximum metabolic capacity, v(max), was around 9.3 mg CN kg fresh weight(-1)h(-1) . The removal of cyanide by plants might be useful in phytoremediation and treatment of wastewater from gold mining. Chemosphere, 2004 Jan, 54(3), 273 - 81 Sorption equilibria of metal ions on bone char; Ko DC et al.; The ability of bone char to adsorb three metal ions, namely, copper(II), zinc(II) and cadmium(II) ions from wastewater has been studied . Three single-component equilibrium systems and three binary equilibrium systems have been measured experimentally . The three single-component equilibrium data were analyzed using the Langmuir and the Sips equilibrium isotherm equations . The Sips isotherm gave a better fit of the experimental data than the Langmuir isotherm based on the sum of squares errors (SSE) analysis . The Cu-Zn, Cu-Cd and Cd-Zn binary equilibrium experimental data were examined by incorporating the Langmuir and the Sips isotherm equations into the ideal adsorbed solution theory (IAST) . The solution methods and the predicted results for the three binary systems at different metal ion compositions have been evaluated . In addition, the application of the IAST to the model prediction for the fixed bed system is presented. Chemosphere, 2004 Jan, 54(3), 235 - 42 Treatment of chemical mechanical polishing wastewater by electrocoagulation: system performances and sludge settling characteristics; Lai CL et al.; Treatment of copper chemical mechanical polishing (CMP) wastewater from a semiconductor plant by electrocoagulation is investigated . The CMP wastewater was characterized by high suspended solids (SS) content, high turbidity (NTU), chemical oxygen demand (COD) concentration up to 500 mgl(-1) and copper concentration up to 100 mgl(-1) . In the present study, electrocoagulation was employed to treat the CMP wastewater with an attempt to simultaneously lower its turbidity, copper and COD concentrations . The test results indicated that electrocoagulation with Al/Fe electrode pair was very efficient and able to achieve 99% copper ion and 96.5% turbidity removal in less than 30 min . The COD removal obtained in the treatment was better than 85%, with an effluent COD below 100 mgl(-1) . The effluent wastewater was very clear and its quality exceeded the direct discharge standard . In addition, sludge settling velocities after electrocoagulation were measured and the data were employed to verify the empirical sludge settling velocity models . Finally, the sludge settling characteristic data were also utilized to establish the relation between the solids flux (G) and the initial solids concentration. Anal Bioanal Chem, 2004 Feb, 378(3), 688 - 96 Epub 2003 Oct 22. Combined biological and chemical assessment of estrogenic activities in wastewater treatment plant effluents; Aerni HR et al.; Five wastewater treatment plant effluents were analyzed for known endocrine disrupters and estrogenicity . Estrogenicity was determined by using the yeast estrogen screen (YES) and by measuring the blood plasma vitellogenin (VTG) concentrations in exposed male rainbow trout (Oncorhynchus mykiss) . While all wastewater treatment plant effluents contained measurable concentrations of estrogens and gave a positive response with the YES, only at two sites did the male fish have significantly increased VTG blood plasma concentrations after the exposure, compared to pre-exposure concentrations . Estrone (E1) concentrations ranged up to 51 ng L(-1), estradiol (E2) up to 6 ng L(-1), and ethinylestradiol (EE2) up to 2 ng L(-1) in the 90 samples analyzed . Alkylphenols, alkylphenolmonoethoxylates and alkylphenoldiethoxylates, even though found at microg L(-1) concentrations in effluents from wastewater treatment plants with a significant industrial content, did not contribute much to the overall estrogenicity of the samples taken due to their low relative potency . Expected estrogenicities were calculated from the chemical data for each sample by using the principle of concentration additivity and relative potencies of the various chemicals as determined with the yeast estrogen screen . Measured and calculated estradiol equivalents gave the same order of magnitude and correlated rather well (R(2)=0.6). Anal Bioanal Chem, 2004 Mar, 378(5), 1243 - 50 Epub 2003 Oct 22. Establishment of traceability of ammonium nitrogen determination in wastewater; Drolc A et al.; A case study is presented for the establishment of traceability for ammonium nitrogen determination in wastewater in a routine laboratory in order to fulfil the requirements of ISO/IEC standard 17025 . The necessary relevant information was obtained from the method validation data, the quality control data and equipment calibration certificates . The method of measurement is described together with the measurement equation, selected traceable reference standards and the associated measurement uncertainty . The major sources of uncertainty of the result of measurement were identified and the combined uncertainty was calculated . Identification of the main uncertainty sources represents the basis for target operations for reducing the measurement uncertainty of this determination. J Hazard Mater, 2003 Oct 31, 103(3), 247 - 61 Anodic oxidation with doped diamond electrodes: a new advanced oxidation process; Kraft A et al.; Boron-doped diamond anodes allow to directly produce OH* radicals from water electrolysis with very high current efficiencies . This has been explained by the very high overvoltage for oxygen production and many other anodic electrode processes on diamond anodes . Additionally, the boron-doped diamond electrodes exhibit a high mechanical and chemical stability . Anodic oxidation with diamond anodes is a new advanced oxidation process (AOP) with many advantages compared to other known chemical and photochemical AOPs . The present work reports on the use of diamond anodes for the chemical oxygen demand (COD) removal from several industrial wastewaters and from two synthetic wastewaters with malic acid and ethylenediaminetetraacetic (EDTA) acid . Current efficiencies for the COD removal between 85 and 100% have been found . The formation and subsequent removal of by-products of the COD oxidation has been investigated for the first time . Economical considerations of this new AOP are included. Environ Sci Technol, 2003 Oct 1, 37(19), 4449 - 56 Removal of hexavalent chromium from wastewater using a new composite chitosan biosorbent; Boddu VM et al.; A new composite chitosan biosorbent was prepared by coating chitosan, a glucosamine biopolymer, onto ceramic alumina . The composite bioadsorbent was characterized by high-temperature pyrolysis, porosimetry, scanning electron microscopy, and X-ray photoelectron spectroscopy . Batch isothermal equilibrium and continuous column adsorption experiments were conducted at 25 degrees C to evaluate the biosorbent for the removal of hexavalent chromium from synthetic as well as field samples obtained from chrome plating facilities . The effect of pH, sulfate, and chloride ion on adsorption was also investigated . The biosorbent loaded with Cr(VI) was regenerated using 0.1 M sodium hydroxide solution . A comparison of the results of the present investigation with those reported in the literature showed that chitosan coated on alumina exhibits greater adsorption capacity for chromium(VI) . Further, experimental equilibrium data were fitted to Langmuir and Freundlich adsorption isotherms, and values of the parameters of the isotherms are reported . The ultimate capacity obtained from the Langmuir model is 153.85 mg/g chitosan. Ambio, 2003 Aug, 32(5), 358 - 61 Disinfection of septic tank and cesspool wastewater with peracetic acid; Heinonen-Tanski H et al.; Wastewaters of private household septic tanks and cesspools have been treated with peracetic acid (1-2 g L(-1)) . Adding 1 g L(-1) peracetic acid to wastewaters was easy and has been found to be effective in destroying enteric indicator microorganisms . The careful mixing of peracetic acid and wastewater was found to be important . Winter periods with frozen soil, ice and snow did not constitute extra problems . The bad smell of these wastewaters almost totally disappeared during the treatment . When wastewaters treated with peracetic acid were emptied into animal slurry tanks, hygienization still continued in the mixture of animal slurry and the wastewaters . These wastewaters could thus be released into agricultural soil without risk of microbiological pollution to groundwaters. J Hazard Mater, 2003 Oct 1, 103(1-2), 65 - 78 Development of a high performance electrochemical wastewater treatment system; Feng C et al.; In order to construct a high performance electrochemical system for practical use in industrial and municipal wastewater treatment, laboratory scale electrochemical experiments were performed to select anode materials by applying pulse voltage . Based on the results obtained from laboratory experiments, a pilot plant of electrochemical treatment system (0.3 m3 h(-1)) was successfully developed, in which electrocoagulation and electrooxidation processes were used . The performance of the treatment system was evaluated by treating domestic wastewater, pond water containing algae and wastewater from hog raising . As a result, production of hydroxyl radicals detected with p-nitrosodimethylaniline (RNO) at Ti/RuO(2)-TiO(2) anode was larger than with a platinum anode, and hydroxyl radicals were not detected at Ti anode . Moreover, a significant difference in electrocatalytic properties for ammonia oxidation between platinum and Ti/RuO(2)-TiO(2) electrodes was not observed from the cyclic voltammogram . The removal of T-N, T-P, NH(4)-N and COD from domestic wastewater and pond water containing algae was approximately 90%, while the removal of chlorophyll-a (chl-a) of algae was approximately 100% . Although the electrochemical treatment system was effective on biologically treated wastewater from hog raising, the treatment of raw wastewater was not remarkable . Therefore, the electrochemical treatment system requires pretreatment when used with wastewater containing high concentrations of suspended solids. FEMS Microbiol Lett, 2003 Oct 10, 227(1), 101 - 6 Isolation of Brachymonas petroleovorans CHX, a novel cyclohexane-degrading beta-proteobacterium; Rouviere PE et al.; A new bacterium that grows aerobically on cyclohexane was isolated from the wastewater plant of a petroleum refinery . This strain grows on a range of light hydrocarbons (C5-C10) as well as on some aromatic compounds such as toluene and m-cresol . Growth on hydrocarbons requires the presence of yeast extract and other complex media components that are not substrates for growth themselves . Strain CHX is resistant to cyclohexane and grows at concentrations up to 2 g l(-1) . Strain CHX branches deeply within the Comamonadeae family of beta-proteobacteria and is tentatively assigned to the Brachymonas genus as Brachymonas petroleovorans CHX. Water Res, 2003 Nov, 37(19), 4645 - 56 Evolution of antibiotic occurrence in a river through pristine, urban and agricultural landscapes; Yang S et al.; A river along the semi-arid Front Range of Colorado was monitored for antibiotics including five tetracycline and six sulfonamide compounds . Existing analytical methods were adapted to measure these compounds in a surface water matrix at environmentally relevant concentrations (0.05 microg/L) . Natural organic matter present in surface waters was confirmed to significantly impact the low-level analysis of tetracyclines (TCs) necessitating the use of standard addition quantification techniques . Five sites along the Cache la Poudre River were monitored for antibiotics encompassing pristine areas without anthropogenic influence, urban areas impacted by wastewater discharges and agricultural areas susceptible to non-point source contaminant runoff . The only site at which no antibiotics were detected was the pristine site in the mountains before the river had encountered urban or agricultural landscapes . By the time the river had exited the urban area, 6 of the 11 antibiotic compounds that were monitored were found in the samples . At Site 5, which had both urban and agricultural influences all five of the TCs monitored were detected indicating both urban and agricultural influences . The concentration of TCs at Site 5 ranged from 0.08 to 0.30 microg/L. Water Res, 2003 Nov, 37(19), 4605 - 12 Nylon fibers as supporting media in anaerobic hybrid reactors: it's effects on system's performance and microbial distribution; Chaiprasert P et al.; The performances of three anaerobic hybrid reactors with various nylon fiber densities per packed bed volume (33, 22, and 11 kg/m(3) in R1, R2, and R3, respectively) as supporting media were evaluated through their ability to remove organic compounds in cassava starch wastewater . In addition, the distributions of non-methanogenic and methanogenic population in the reactors were investigated . During a 6-month operation, the organic loading rate was increased in stepwise from 0.5 to 4.0 kg COD/m3/day and the hydraulic retention time (HRT) shortened to 5.4 days . The COD removal efficiency was more favorable in R1 (87%) and R2 (84%) than in R3 (70%) . The total biomass in the reactors with greater nylon fiber densities was also higher and increased from 20.4 to 67.3 g VSS and to 57.5 g VSS in R1 and R2, respectively . When the HRT was further shortened to 3 days, however, the efficiency of both reactors demonstrated a declining trend and reached 74% in R1 and 61% in R2 . The distribution of microbial populations involved in the reactors was determined using the Most Probable Number technique . The result showed the lowest number of methanogens in R3 which correlated well to its relatively low efficiency . The number of non-methanogens in all reactors was, nonetheless, comparable . By shortening the HRT to 3 days, the methanogenic population in R2 diminished in both attached and suspended biomass whereas a slight reduction was detected only in the attached biomass of R1. Anal Bioanal Chem, 2004 Jan, 378(2), 470 - 8 Epub 2003 Oct 16. The chromatographic behavior of group (IIB) metal ions on polyurethane foam functionalized with 8-hydroxyquinoline; El-Shahat MF et al.; Polyurethane foam functionalized with 8-hydroxyquinoline has been prepared by coupling the foam matrix with 8-hydroxyquinoline (oxine) through an azo spacer . The oxine-bonded foam (Ox PUF) was characterized by use of different tools (UV-Vis spectra, IR spectra, density, and stability) . Ox PUF was found to be very suitable for separation and preconcentration of trace metals, e.g . Zn(II), Cd(II), and Hg(II) ions, from wastewater in the pH ranges 2-12, 9-12, and 3-6, respectively . Various conditions influencing the sorption of these metal ions on to Ox PUF were optimized . Extraction of the metal ions was accomplished in 15 to 20 min . Study of the variation of the sorption of the tested metal ions with temperature yielded average values for DeltaH, DeltaS, and DeltaG of 41.99, 158.23, and -5.1 kJ mol(-1), respectively . The capacities of the foam material were 0.27, 0.16, and 0.09 mmol g(-1) for Zn(II), Cd(II), and Hg(II), respectively . Preconcentration factors >50 were achieved (RSD approximately 6.18) . The quantitative results were obtained from experiments performed using certified reference materials. J Environ Sci (China), 2003 Sep, 15(5), 697 - 700 Treatment of black liquor from the papermaking industry by acidification and reuse; Yang WB et al.; Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse . The experimental parameters and conditions were discussed in detail . The experimental results indicated that the treatment process mentioned in this article is an effective process for the treatment of black liquor from the papermaking industry . By the treatment, the solid materials in black liquor are transferred into two by-products and the other components are reused or evaporated . Thus, no wastewater except some condensation water would be discharged in pulping process and the problem of pollution of black liquor would be effectively solved. J Environ Sci (China), 2003 Sep, 15(5), 652 - 61 United membrane biological reactor in the treatment of wastewater; Zhou JT et al.; The united membrane biological reactor( UMBR) was studied for the treatment of some simulate and municipal wastewater . The removal efficiency for COD and turbidity are greater than 80% and 99% respectively . Effluent COD is less than 100 mg/L while turbidity less than 5 . The removal of LAS in bath wastewater is greater than 70% . In treatment of dinning-hall wastewater, removal of fatty oil is greater than 90%, and its concentration in effluent is less than 5 mg/L . The match of biological reactor and the membrane separation component were calculated . The stable performance of wastewater treatment can be maintained by the optimization of operation conditions and the cleanout of membranes. J Environ Sci (China), 2003 Sep, 15(5), 633 - 8 Immobilized chitosan as a selective absorbent for the nickel removal in water sample; Wu JM et al.; Method for preparation of chitosan immobilized on silica gel (CTS-silica) was described . The CTS-silica was used as absorbent for the absorption of nickel in water . The results showed that this absorbent had relatively high selectivity and strong affinity to nickel . The maximum absorption capacity for nickel can reach 667 mg/g of chitosan . Factors that affect the absorption capacity, such as pH, ion strength and the presence of calcium, EDTA and the mechanism of absorption were discussed in detail . The absorbent can be regenerated with acid and reused for several times . The recovery rate for nickel can reach 99.99% . This absorbent filled in a column can be used in nickel removal from wastewater and drinking water. J Environ Sci (China), 2003 Sep, 15(5), 628 - 32 Comparison of decolorization of reactive microorganisms isolated from various sources; Padamavathy S et al.; Azo dyes are among the oldest man-made chemicals and they are still widely used in the textile, printing and the food industries . About 10% - 15% of the total dyes used in the industry is released into the environment during the manufacturing and usage . Some dyes and some of their N-substituted aromatic bio-transformation products are toxic and/or carcinogenic and therefore these dyes are considered to be envionmental pollutants and health hazards . These azo dyes are degraded by physico-chemical and biological methods . Of these, biological methods are considered to be the most economical and efficient . In this work, attempts were made to degrade these dyes aerobically . The organisms which were efficient in degrading the following azo dyes-Red RB, Remazol Red, Remazol Blue, Remazol Violet, Remazol Yellow, Golden Yellow, Remazol Orange, Remazol Black- were isolated from three different sources viz., wastewater treatment plant, paper mill effluent treatment plant and tannery wastewater treatment plant . The efficiency of azo dye degradation by mixed cultures from each source was analyzed . It was found that mixed cultures from tannery treatment plant worked efficiently in decolorizing Remazol Red, Remazol Orange, Remazol Blue and Remazol Violet, while mixed cultures from the paper mill effluent worked efficiently in decolorizing Red RB, Golden Yellow and Remazol Yellow . The mixed cultures from wastewater treatment plant efficiently decolorized Remazol Black. J Environ Sci (China), 2003 Sep, 15(5), 622 - 7 Plants grown on sewage sludge in South China and its relevance to sludge stabilization and metal removal; Samake M et al.; The production of sewage sludge in China has been increasing sharply in order to treat 40% of the municipal sewage in 2005 as planned by central government . The main sludge disposal method is landfill owing to heavy metal contamination, but it presents an attractive potential for agricultural land application . Experiments were carried out to study the simultaneous metal removal and sludge stabilization by plants . The sludge samples were collected from Datansha Wastewater Treatment Plant of Guangzhou, it contained excessive Cu and Zn compared with the Chinese National Standard for Agricultural Use of Sewage Sludge . Plants growing on sludge beds were investigated to follow their growth and metal uptake . 30 sludge plants were identified during 1 year's observation . A Zn high-accumulating and high growth rate plant(Alocasia macrorrhiza) was selected and grown on sludge beds in plots . The water, organic matter, heavy metals and nutrients contents, the E . coli number and the cress seed germination index were monitored for the sludge samples collected monthly . The plant growth parameters and its heavy metals contents were also determined . The sewage sludge treated by plants could be stabilized at about 5 months, the E . coli number was significantly decreased and the cress seed germination index attained 100% . Crop on sludge could ameliorate the sludge drying . The experiments are continuing to find out the appropriate plant combination for simultaneous sludge stabilization and metal removal for an acceptable period . Comparisons between the proposed processes and other methods for treating produced sludge such as composting, chemical andbacterial leaching were discussed. Int J Epidemiol, 2003 Oct, 32(5), 772 - 7 Poliovirus detection in wastewater and stools following an immunization campaign in Havana, Cuba; Mas Lago P et al.; BACKGROUND: Recent outbreaks of poliomyelitis caused by vaccine-derived virus have raised concerns that vaccine-derived poliovirus may continue to circulate after eradication . In these outbreaks, the virus appears to have replicated for > or =2 years before detection . Early detection is critical for an effective response to these outbreaks . Although acute flaccid paralysis (AFP) surveillance will remain the standard for poliovirus detection, wastewater sampling could be a useful supplement . In this study, we evaluated the sensitivity of wastewater sampling by concurrently collecting stools from children aged < 3 years attending two neighbourhood clinics in Havana, Cuba, and wastewater from the same neighbourhoods . METHODS: Sample collection was begun during the third week after the national immunization campaign, continued weekly through the seventh week, and was repeated during weeks 15 and 19 . Virus detection and titration were performed using both cell culture and polymerase chain reaction techniques . RESULTS: Wastewater sampling was found to be at least as sensitive as stool sampling under these conditions . Poliovirus was isolated from children through week 7, suggesting that viral shedding reached undetectable levels between weeks 8 and 14 . The last virus-positive wastewater sample was collected during week 15 . CONCLUSIONS: Wastewater sampling under the conditions studied can be a sensitive supplement to AFP surveillance . Similar studies under different conditions are needed to determine the role of wastewater sampling in post-eradication surveillance. Comp Biochem Physiol C Toxicol Pharmacol, 2003 Oct, 136(2), 117 - 25 Effects of municipal effluents on serotonin and dopamine levels in the freshwater mussel Elliptio complanata; Gagne F et al.; Sex differentiation and gametogenesis represent critical steps in the reproductive process and are subject to hormonal control by serotonin, dopamine and steroids such as estradiol-17beta and testosterone . The purpose of this study sought to examine the endocrine-disrupting activity that a primary-treated municipal effluent might have on the metabolism of biogenic amine levels . First, serotonin receptors transfected in Chinese hamster ovary (CHO) cells were used to screen for the presence of serotonin receptor agonist or antagonist . Second, one group of Elliptio complanata mussels were exposed to single compounds likely to be found in municipal wastewaters and another group was exposed in situ to the municipal effluent plume for 90 days in experimental cages . Results showed that solid phase C-8 extracts of surface water downstream a municipal effluent could activate the transport of serotonin by receptors at a distance of at least 5 km from its outfall thereby indicating the presence of serotonin mimics in the effluent dispersion plume . Levels of serotonin and monoamine oxidase (MAO) activity in nerve ganglia of mussels exposed for 90 days to the municipal effluent were, respectively, reduced and increased at a distance 10-km downstream . Injections of estradiol-17beta and nonylphenol in mussels decreased the levels of serotonin and dopamine, but increased MAO activity in the gonad and nerve ganglia . Exposure to estrogenic chemicals present in municipal effluents may therefore alter the normal metabolism of serotonin and dopamine, both of which are involved in sexual differentiation in bivalves and fish . Chemicals acting through E2 receptor-mediated pathways and serotonin receptors are likely to cause the observed effects. J Chromatogr A, 2003 Oct 3, 1014(1-2), 129 - 39 Potential of microemulsion electrokinetic chromatography for the separation of priority endocrine disrupting compounds; Fogarty B et al.; This work examines the potential of microemulsion electrokinetic chromatography for the separation of several priority endocrine disrupting compounds (EDCs) . The optimised microemulsion system comprised 25 mM phosphate buffer pH 2, 80 mM octane, 900 mM butanol, 200 mM sodium dodecyl sulphate and was further modified with 20% propanol . The use of a low pH buffer resulted in the suppression of electroosmotic flow within the capillary . Reversal of the conventional electrode polarity resulted in faster migration of hydrophobic compounds . Test analytes included the octylphenol, nonylphenol and nonylphenol diethoxylate, which are breakdown products of the alkylphenolic detergents . The synthetic oestrogens diethylstilbestrol and ethynyloestradiol were also included in the separation along with the plastic monomer bisphenol-A . Test analytes were selected due to their reported presence in environmental samples namely industrial and domestic wastewater treatment effluents and sludges . Using the optimised method a separation of six EDCs was achieved within 15 min . The optimised method was then applied to the analysis of a spiked wastewater influent sample with UV detection of all six compounds at 214 nm. Huan Jing Ke Xue, 2003 Jul, 24(4), 105 - 8 {Phosphorus removal of agriculture wastewater through subsurface constructed wetland}; Zhang R et al.; Phosphorus removal in subsurface constructed wetland treating agriculture non-pointed wastewater was studied in pilot-scale . The experimental results showed that the removal rates of TP increased with HRT increasing when the nominal hydraulic retention time was less than 5 days . The pH decreased distinctly when the retention time was too longer in the batch and sequence style, it may bring on a lower removel rate of TP . The amount of TP that can be removed by harvesting were about 15.8% and 9.5% compared to the total quantity of removing in Phragmitas communis and zizania caduciflora constructed system respectively . Temperature impacted on the removel of TP, the removel rate of TP decreased 30% in the winter compared to summuer. Huan Jing Ke Xue, 2003 Jul, 24(4), 68 - 72 {Bulking controls induced by nitrogen insufficiency in yeast system}; Han Y et al.; The effect of nitrogen addition to salad oil manufacturing wastewater system was studied . The results of batch experiments demonstrated: 1 . addition of nitrogen was helpful to improve oil removal, and the oil removal rate was above 90% when COD/N value was between 50/1 and 20/1; 2 . addition of nitrogen improved the sludge settleability, which was much better under COD/N value of 50/1 and 20/1 . In the continuous experiment, the value of slude volume index(SVI) was between 100 and 200, and the removal rates of oil and COD were above 95% and 90%, respectively when the COD/N ratio was kept at value of 20/1 . Nitrogen addition to salad oil manufacturing wastewater system is an effective method for preventing or controlling sludge bulking. Huan Jing Ke Xue, 2003 Jul, 24(4), 35 - 40 {Effect of inorganic nitrogen compounds and pH on the growth of duckweed}; Chong Y et al.; The use of duckweed in domestic wastewater treatment was paied increasing attention recently . But inorganic nitrogen compounds and pH of wastewater possibly affect the growth of duckweed . The effect of ammonia, nitrate and pH on the growth of Lemna minor L., a common spiece in China, was assessed with laboratory scale experiments . The experiments used artificial culture with different levels of pH, ammonia and nitrate concentrations . The experimental results indicated that the lowest value of pH Lemna minor can tolerate was between 5-6, and it can grow well in pH from 6 to 9 . The growth rate of Lemna minor was inhibited gradually with increasing concentration of ammonia . The toxicity of ammonia was a result of both forms, NH3 and NH4+ . Compared to NH4+, the effect of NH3 was much stronger . Nitrate had few inhibitory on the growth of Lemna minor . The increase in ammonia and nitrate concentrations can increase the chloropyll content of Lemna minor . Activity of peroxidase of Lemna minor in ammonia culture was higher than that in nitrate culture because of the toxicity of ammonia. J Environ Manage, 2003 Oct, 69(2), 193 - 200 Fed-batch and batch operating mode analysis of a stirred anaerobic sequencing reactor with self-immobilized biomass treating low-strength wastewater; Rodrigues JA et al.; This work presents an analysis of a stirred anaerobic sequencing discontinuous reactor with different substrate feeding strategies resulting in batch, fed-batch/batch and fed-batch operating modes . The reactor, containing granulated biomass, was fed with approximately 2.0L of synthetic domestic wastewater with Chemical Oxygen Demand of nearly 500 mg/L per cycle and operated at 30 degrees C and 50 rpm . Three feeding strategies with a total cycle time of 6 h, including 30-min settling, were adopted: batch mode with a fill cycle of 6 min, a fed-batch/batch mode with fill cycles of 60, 120 and 240 min and fed-batch mode with a fill cycle of 320 min . The system attained average non-filtered and filtered substrate removal efficiency of 78 and 84%, respectively, for all operating conditions, presenting good stability, solid retention and no granule break-up . A first order kinetic model with a residual organic matter concentration was proposed to analyze the influence of the feeding strategy on the performance during a cycle and bicarbonate alkalinity and total volatile acids concentration profiles were also quantified in order to verify the transient stability behavior. J Environ Manage, 2003 Oct, 69(2), 187 - 91 Removal of heavy metals in rinsing wastewater from plating factory by adsorption with economical viable materials; Katsumata H et al.; The removal of heavy metals from plating factory wastewater with economical materials was investigated by the column method . Montmorillonite, kaolin, tobermorite, magnetite, silica gel and alumina were used as the economical adsorbents to wastewater containing Cd(II), Cr(VI), Cu(II) and Pb(II) . This removal method of heavy metals proved highly effective as removal efficiency tended to increase with increasing pH and decrease with increasing metal concentration . The removal percentages by adsorption onto montmorillonite, tobermorite, magnetite, and silica gel showed high values for all metals . From the results for the heat of adsorption, the adsorption process in the present study might be chemisorption . The proposed method was successfully applied to the removal of Cd(II), Cr(VI) and Cu(II) in rinsing wastewater from plating factory in Nagoya City, Aichi Prefecture, Japan . Since the economical adsorbents used can be obtained commercially because they are easily synthesized, the wastewater treatment system developed is rapid, simple and cheap for the removal of heavy metals. Chemosphere, 2003 Dec, 53(10), 1211 - 20 Experimental design of Fenton and photo-Fenton reactions for the treatment of cellulose bleaching effluents; Torrades F et al.; Multivariate experimental design was applied to the treatment of a cellulose conventional bleaching effluent in order to evaluate the use of the Fenton reagent under solar light irradiation . The effluent was characterised by the general parameters total organic carbon (TOC), chemical oxygen demand and color, and it was analysed for chlorinated low molecular weight compounds using GC-MS . The main parameters that govern the complex reactive system: Fe(II) and H(2)O(2) initial concentration, and temperature were simultaneously studied . Factorial experimental design allowed to assign the weight of each variable in the TOC removal after 15 min of reaction . Temperature had an important effect in the organic matter degradation, especially when the ratio of Fenton reagents was not properly chosen . Fenton reagent under solar irradiation proved to be highly effective for these types of wastewaters . A 90% TOC reduction was achieved in only 15 min of treatment . In addition, the GC-MS analysis showed the elimination of the chlorinated organic compounds initially detected in the studied bleaching effluents. Biotechnol Adv, 1988, 6(4), 725 - 70 The potential of microalgal biotechnology: a review of production and uses of microalgae; de la Noue J et al.; An overview of the various aspects, promises and limitations of microalgal biotechnology is presented . The factors of importance in microalgal cultivation as well as the culture systems are briefly described . Microalgal biomasses can fulfil the nutritional requirements of aquatic larvae and organisms . The biochemical composition of algae can be improved by the manipulation of culture conditions . The nutritive value of the microalgal biomasses for human and animal consumption is also commented upon as well as some socio-economical aspects . Among the sources of required nutrients (N, P), wastewaters and manures can upgraded as culture media for microalgae the safety of which has to be evaluated . Harvesting of the biomass is one of the bottlenecks . The various techniques, physical, physico-chemical and biological are outlined and their feasibility and economic interest examined . Microalgal biomasses can be submitted to various technological transformations . Various processes are reviewed in the light of their effects on safety and nutritional value . The possible extraction of fine chemicals and the preparation of protein concentrates is also reported on . The various uses of microalgae lead to a possible competition, to be evaluated, between systems for the production of food, energy and chemicals . The review finally covers the application of genetic manipulation to microalgae. Biotechnol Adv, 1984, 2(2), 357 - 75 Anaerobic fluidised bed for the purification of effluents from chemical and mechanical pulping; Salkinoja-Salonen M et al.; Anaerobic treatment has seldom been used for wastewaters from the pulp and paper industry and other branches of the chemical industry . Escape of volatile pollutants to the atmosphere, which always occurs during aerobic treatment, is avoided, and much less sludge is being produced than in an aerobic process . The greatest obstacle for using anaerobic treatment in the pulp and paper industry is the large wastewater volume, which necessitates short hydraulic detention times, because the treatment is to occur in an enclosed space . We used solid carrier particles to prevent wash-out of biomass from the reactor at high hydraulic loading, and an up-flow system in order to be able to use very small carrier particles, maximizing the surface area for biomass attachment . In this paper we describe and discuss the results obtained with this type of anaerobic reactor (fluidised bed) at bench and semitechnical scale for wastewaters from pressurized ground wood pulping and paper manufacture, sulphite pulp evaporator condensate and bleach waste . Earlier work with Kraft pulp bleaching effluent and thermomechanical pulping wastewater and evaporator condensates using anaerobic reactors is also discussed . The results obtained thus far show that there are several wastewater streams from the pulping industry, where 60 to 90% of the dissolved organic pollutants (measured as COD(Cr) or TOC) was biodegraded within 4 to 24 h . The high strength waste streams (COD(Cr) >2000 mg O(2) 1(-1)) allowed organic space load of 4 to 10 kg COD(Cr) m(-3) reactor volume d(-1) . With low strength wastes the hydraulic loading was the limiting factor. Biotechnol Adv, 1992, 10(4), 549 - 59 Bioaugmentation for enhancing biological wastewater treatment; Stephenson D et al.; The literature on bioaugmentation products has been reviewed . Their manufacture and method of use is explained . The various applications are listed and the independent investigations, as opposed to manufacturers accounts, at laboratory and full scale are reviewed . The economics and kinetic modelling are also discussed . In laboratory investigations bioaugmentation often failed, whereas at full scale it was often successful, probably due to the imposition of steady state at laboratory scale . Most products require a period of acclimatisation before working; this and other possible reasons for failure are discussed. Biotechnol Adv, 1993, 11(4), 781 - 812 Bioremoval of heavy metals by the use of microalgae; Wilde EW et al.; Bioremoval, the use of biological systems for the removal of metal ions from polluted waters, has the potential to achieve greater performance at lower cost than conventional wastewater treatment technologies for metal removal . Bioremoval capabilities of microalgae have been extensively studied, and some commercial applications have been initiated . Although microalgae are not unique in their bioremoval capabilities, they offer advantages over other biological materials in some conceptual bioremoval process schemes . Selected microalgae strains, purposefully cultivated and processed for specific bioremoval applications, have the potential to provide significant improvements in dealing with the world-wide problems of metal pollution . In addition to strain selection, significant advances in the technology appear possible by improving biomass containment or immobilization techniques and by developing bioremoval process steps utilizing metabolically active microalgae cultures . The latter approach is especially attractive in applications where extremely low levels of residual metal ions are desired . This review summarizes the current literature, highlighting the potential benefits and problems associated with the development of novel algal-based bioremoval processes for the abatement of heavy metal pollution. J Environ Qual, 2003 Sep-Oct, 32(5), 1851 - 6 Biosolids-derived nitrogen mineralization and transformation in forest soils; Wang H et al.; Utilization of biosolids through land application is becoming increasingly popular among wastewater managers . To minimize the potential contamination of receiving waters from biosolids-derived nitrogen (N), it is important to understand the availability of N after land application of biosolids . In this study, four secondary biosolids (two municipal and two pulp and paper industrial biosolids) were used in a laboratory incubation experiment to simulate N mineralization and transformation after land application . Municipal biosolids were from either aerobically or anaerobically digested sources, while pulp and paper industrial biosolids were from aerated wastewater stabilization lagoons . These biosolids were mixed with two New Zealand forest soils (top 100 mm of a volcanic soil and a brown soil) and incubated at two temperatures (10 and 20 degrees C) for 26 wk . During incubation, mineralized N was periodically leached from the soil-biosolids mixture with 0.01 M CaCl2 solution and concentrations of NH4 and NO3 in leachate were determined . Mineralization of N from aerobically digested municipal biosolids (32.1%) was significantly more than that from anaerobically digested biosolids (15.2%) . Among the two pulp and paper industrial biosolids, little N leached from one, while as much as 18.0% of total organic N was leached from the other . As expected, mineralization of N was significantly greater at 20 degrees C (average 22.8%) than at 10 degrees C (average 9.7%) . It was observed that more N in municipal biosolids was mineralized in the brown soil, whereas more N in pulp and paper industrial biosolids mineralized in the volcanic soil . Transformation of NH4 to NO3 was affected by soil type and temperature. J Environ Qual, 2003 Sep-Oct, 32(5), 1677 - 83 Assessing the application of an additive model to estimate toxicity of a complex effluent; Ross KE et al.; A number of industries monitor levels of chemicals in their effluent, but few have undertaken prolonged biological monitoring of this wastewater . The focus of the present study was to determine whether past chemical data for effluent from a lead smelter could be used to estimate its past toxicity . Since the interactive effects of metals in effluents are often assumed to be additive, it was hypothesized that an additive model, 100/{sigma(metal concentration in effluent/EC50 for individual metal)}, could be used to generate an EC50 from chemical data (where EC50 is the concentration of test material that affects 50% of the test organisms) . To test the approach, a larval development toxicity test with the marine polychaete, Galeolaria caespitosa, was used to test 26 separate samples of effluent from a lead smelter, generating empirical EC50 values . EC50 values for each individual metal in the effluent were also generated using the larval development toxicity test . The concentrations of trace metals in each effluent sample were determined and, using the additive model, EC50 values were calculated . For the majority of effluent samples tested, the additive model underestimated toxicity, suggesting the presence of additional unidentified contaminants in the effluent samples . Additionally, a nonlinear rather than linear regression curve was found to best describe the relationship between the model and empirically derived EC50 values . This relationship was then used to estimate past trends in toxicity of the smelter effluent . Forty-eight percent of the variability in measured toxicity was explained by the model, with the model underestimating toxicity in the majority of samples. J Environ Qual, 2003 Sep-Oct, 32(5), 1583 - 90 The capacity of duckweed to treat wastewater: ecological considerations for a sound design; Korner S et al.; Duckweed species are promising macrophytes for use in sustainable wastewater treatment due to their rapid growth, ease of harvest, and feed potential as a protein source . This paper reviews growth rates of different duckweed species on wastewater and ammonia toxicity to duckweed and summarizes insights into the mechanism of organic matter and nutrient removal . Results were gained from laboratory experiments in small, shallow, duckweed-covered semicontinuous batch systems . Growth rates on different types of wastewater vary considerably among different species . Ammonia is toxic for duckweed in both the ionized and un-ionized forms . Duckweed, however, can be used to treat wastewater containing very high total ammonia concentrations as long as certain pH levels are not exceeded . The degradation of organic material is enhanced by duckweed through both additional oxygen supply and additional surface for bacterial growth . The duckweed mat with attached bacteria and algae is, independent of the loading rates, responsible for three-quarters of the total nitrogen (N) and phosphorus (P) loss in very shallow systems . Based on our results we suggest that full-scale pilot plants with duckweed should be shallower than the range encountered in the literature . A harvesting schedule that allows doubling times of 2 to 3.5 d, maintenance of a full coverage, and plug flow conditions are recommended. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(11), 2621 - 31 Removal of reactive dye from wastewater by adsorption using ECH cross-linked chitosan beads as medium; Chiou MS et al.; The feasibility of the removal of reactive dye from wastewater using a novel adsorbent, ECH cross-linked chitosan beads, as medium was examined . The effect of the pH and the initial concentration of the dye (RR222) solution on the adsorption capacity of the ECH cross-linked chitosan beads were also investigated . It was found that the initial dye concentration and the pH of the solution significantly affected the adsorption capacity . An increase in initial dye concentration results in the increase of adsorption capacity while an acidic pH was found to be favorable for the adsorption of dye . It was also found that the equilibrium adsorption of RR222 could be adequately described by using the Langmuir model (r2 > or = 0.999) . Moreover, results showed that the adsorption rate of RR222 onto ECH cross-linked chitosan beads could be described by using the second-order kinetic model, suggesting that chemical sorption instead of mass transfer was the rate-limiting step for the adsorption process . The maximum monolayer adsorption capacity obtained from the Langmuir model was extremely high as compared to the data reported in literature; 2252 g/kg at 30 degrees C with a pH of 3.0 . Therefore, ECH cross-linked chitosan beads could be a feasible medium for the removal of reactive dye from wastewater and potentially an alternative for the decolorization of wastewater. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(11), 2537 - 47 Odor control in evaporation ponds treating olive mill wastewater through the use of Ca(OH)2; Lagoudianaki E et al.; Different amounts of Ca(OH)2 were added in 2 L beakers containing 1 L of olive mill wastewater (OMW) . The mixture was stirred for 45 min and left to settle . Wastewater analysis was used in order to determine the effect of the different amounts of calcium hydroxide in the treating process, three days after the application . The Odor Detection Threshold was used for determining the effect of the treatment in the odors produced in the beakers, three and 30 days after . Both sets of measurements indicated an important reduction in wastewater pollutants and odor emission when 10 g/L of Ca(OH)2 were added . In order to evaluate these results in more realistic conditions . 10 L plastic containers were filled with 6 L of OMW, relevant amounts of Ca(OH)2 were added, the mixture was stirred manually and left to settle in the open . Again, 10 g/L of calcium hydroxide produced the best results in odor reduction and wastewater treatment. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(11), 2521 - 35 VOC emission characteristics of petrochemical wastewater treatment facilities in southern Taiwan; Cheng WH et al.; The wastewater treatment plants (WWTPs) of three representative petrochemical plants in southern Taiwan were sampled to investigate their VOC emission characteristics . Generally, emissions decline along the process flow, while the VOC concentration accumulates to as much as around 2400mg/m3 (as total hydrocarbons) at several closed vessel vents during the primary treatment . VOC emission rates (g/s) and fluxes (g/m2 hr) exhibit a similar trend of reducing concentrations in the WWTPs . From the field analysis data . VOC emission potential is best indicated by the concept of emission flux rather than concentration or emission rate . The Water 8 emission model version 4, developed by the U.S . EPA in 1995, was used to simulate the emission rate . The output results were compared to the calculated VOC liquid-gas mass equilibrium based essentially on the saturated gas concentration (Cg*) of the individual VOC components in wastewater . The comparisons clearly identified the proposed mass transfer approach using (Cg* as a reliable timesaving alternative to Water 8, which requires numerous input parameters and water analysis data. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2369 - 79 Anaerobic digestion of municipal sludges with high silt content using granular seed; Atilla B et al.; The performance of anaerobic digestion of municipal sludge having high inorganic solid/silt in Tuzla Wastewater Treatment Plant (TWWTP) in Istanbul was evaluated using granular seed . High silt/solid content is the main problem related to wastewater collection system in TWWTP . Due to high TSS concentration of the influent, inorganic solid ratio reaches to 60-70% in the primary sludge that makes sludge digestion very difficult . The aim of this study was to evaluate the detrimental effects of inorganic silt/clay on anaerobic sludge solubilization of the primary sludge (PS), of the biological sludge (BS), and of the mixed sludge (50%PS + 50%BS) . Anaerobic solubilization was carried out in continuously stirred anaerobic reactors at mesophilic temperature (35 degrees C) . Results indicated significant total biogas productions in all reactors during digestion period . The biogas production of the primary sludge was higher than the biogas productions of the mixed sludge and the biological sludge . The methane contents of the primary, biological . and mixed sludges were found as around 72, 78, and 75%, respectively . When all types of sludges were used as substrates, the reactors removed VSS with a corresponding production of Soluble COD (SCOD) . The greatest degree of hydrolysis/acidogenesis was observed in all types of sludges in about 10 days of operation and became almost stable which indicated that the reactors were still in the hydrolysis/acidogenesis phase . VFAs measurements were well matched with SCOD results . In all reactors, observation of the conversion into methanogenic phase in about 1.5 month was not possible which might be attributed to high inorganic silt/clay and salinity content of TWWTP . High inorganic silt/clay and salinity might have decreased the biodegradability of all sludges and methanogenesis could not operate in early periods of digestion . Higher SCOD decreases might have been possible if longer treatment time and more optimal conditions for anaerobic solubilization were applied . The pH did not fall below the unfavorable range in all reactors during the study. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2339 - 48 Recycling and reuse of wastewater from a new-developed community using sand filtration, ultrafiltration, and ozonation; Ni CH et al.; In this study, the pilot apparatus combined with sand filtration, ozonation and ultrafiltration was established . Wastewater from the secondary treatment effluent in the new-developed community was taken as the sample for looking into the feasibility of domestic wastewater reuse and recycling . The test results by sand filtration, sand filtration/ultrafiltration, sand filtration/ozonation, and sand filtration/ultrafiltration/ozonation were compared for looking for appropriate treatment processes applied in the domestic wastewater reuse and recycling . Finally, cost analysis was carried out and sand filtration/ozonation process was suggested to be one of the best processes . The total cost is about 0.1-0.32 USD dollars per cubic meter of produced water by considering the capital and operation cost for five years in the small domestic wastewater treatment plant (50-750 CMD). J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2329 - 38 Operational strategies for a small wastewater treatment plant using OUR, microscopic analysis, and toxicity test; Meric S et al.; This study was focused on determining the optimal operational conditions of a small domestic wastewater treatment plant (SWP) with a flow rate of 1000 m3 d(-1) using oxygen uptake rate (OUR) data, microscopic analyses, and effluent toxicity testing with Daphnia magna in parallel to wastewater characterization . Chemical analyses of nine samples, taken from different points of the treatment plant over a nine months period, presented strong domestic wastewater characteristics . The plant performance for meeting discharge standards was not sufficient enough for TP parameter . Aeration capacity and sludge recycle ratio were adjusted to improve the performance of the system and to prevent any operational problems, such as bulking . Although the inflow was 100% toxic, effluent toxicity following treatment was decreased to 5% . Filamentous bacteria were in "excessive" amount . The dominant filamentous bacteria species were determined as Nostocoioda limicola II . Reevaluation of the discharge limits with respect to nutrient removal, geographic location, and receiving water quality subject to treatment effluent discharges. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2301 - 15 Aromatic amine degradation in a UASB/CSTR sequential system treating Congo Red dye; Isik M et al.; In this study an anaerobic (upflow anaerobic sludge blanket reactor)/aerobic (completely stirred tank reactor) sequential system was used to treat a synthetic wastewater with minerals and co-substrate together with 100-4000 mg L(-1) of Congo Red dye (Direct red 28) (CR), which is a banned azo dye in Turkey . The effect of hydraulic retention time (HRT) on the decolorization and the COD removal efficiency was investigated at constant 100 mg L(-1) Congo Red concentration . 77% of COD and 95% of color was removed at a HRT of 0.486 days and a maximum organic loading rate of 6.656 kg COD m(-3) day(-1) in the anaerobic/aerobic stage . In the continuous operations, 88% of COD, 99% of color and 91% of total aromatic amine (TAA) were removed at a HRT of 3.60 days and at a CR concentration of 4000 mg L(-1) . This corresponds to an organic loading rate of 1.81 kg COD m(-3) day(-1), and a CR dye loading rate of 46.37 g dye m(-3) h(-1), respectively, in the whole system . The TAA produced under anaerobic conditions was ultimately removed in the aerobic stage, resulting in very low aromatic amine recoveries (5-18%) in the last one . Therefore the aerobic effluents exhibited higher IC50 and specific methanogenic activities (SMA) compared to anaerobic and dye containing samples, indicating the reduced toxicity. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2251 - 8 Clay mineral batch process for color removal of textile wastewaters; Armagan B et al.; Textile industry effluents exhibit large amounts of dye chemicals, which create severe water pollution . It is therefore important to reduce the dye concentration in the wastewater before discharging into the environment . In this study, the ability of sepiolite to uptake different reactive dyes is investigated . The dyes used in the experiments are Everzol Black B, Everzol Yellow 3RS H/C, and Everzol Red 3BS . A number of parameters on adsorption has been investigated in order to establish the adsorption pattern of sepiolite . The effect of conditioning time, solid/liquid ratio, pH, temperature, and dye concentrations on adsorption are studied . Adsorption isotherms for different reactive dyes have been obtained using both natural and modified sepiolites . The maximum capacity of natural sepiolite for the reactive dyes occurs at around 0.1-1 mg/g . Therefore, the natural sepiolite appears to have a little capacity for reactive dyes . The zeta potential profiles of natural and modified sepiolites against pH are also examined . The modified sepiolite exhibited ten times higher performance than the natural sepiolite. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2219 - 28 Treatment of Cr(VI) and phenol by illuminated TiO2; Lee SM et al.; Industrial wastewater from organic chemical manufacturing and metal plating industries may contain significant amounts of refractory organic matter and heavy metals . Heavy metals such as Cr(VI) and refractory organic matter like phenol were simultaneously removed by reduction and mineralization, respectively, during photocatalytic process . Therefore, this study was carried out to evaluate the effects of phenol on the removal of Cr(VI) in several environmental conditions . Cr(VI) and phenol were more effectively eliminated in UV/TiO2 condition than either by UV or TiO2-alone . The removal efficiencies of Cr(VI) increased as the pH of the TiO2 slurry decreased, the concentration of phenol increased up to 10 mg L(-1), and nitrogen gas was used . Otherwise, the removal efficiencies of phenol were higher at O2-purged system and neutral pH . Without regard to purging gases, complete Cr(VI) removal was observed at pH 4 after 80 min while 90% phenol destruction and 60% mineralization were found after 120 min . It wasfound that application of photocatalytic reaction by using illuminated TiO2 to treat wastewater containing both Cr(VI) and phenol was possible. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2209 - 18 Comparative evaluation of the results for the synthetic and actual reactive dye bath effluent treatment by nanofiltration membranes; Koyuncu I et al.; In this study, the results of nanofiltration experiments carried out on reactive dye house wastewaters are presented . The experiments were performed using lab-scale membrane system . Permeate quality was appropriate to reuse permeate in dyeing process again . Pretreatment and neutralization were the parameters which are very important for the recovery of high amounts of salt and water at the permeate stream . In addition, use of HCl instead of H2SO4 for neutralization increased the NaCl recovery. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2125 - 34 Design of sequencing batch reactors for biological nitrogen removal from high strength wastewaters; Artan N et al.; This paper covers an evaluation of more than twenty full-scale industrial wastewater treatment plants employing sequencing batch reactor (SBR) process mainly for carbon removal and a pilot-scale SBR designed for carbon and nitrogen removal from tannery effluent . The study highlights the major features of the SBR technology and proposes a rational dimensioning approach for carbon and nitrogen removal SBRs treating high strength industrial wastewaters based on scientific information on process stoichiometry and modeling, also emphasizing practical constraints in design and operation. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2101 - 11 Treatment of mixed pharmaceutical industry and domestic wastewater by sequencing batch reactor; Ileri R et al.; Raw mixed pharmaceutical industry and domestic wastewater characteristics are such as BOD5 = 90-130 mg L(-1), COD = 200-300 mg L(-1), SS = 900 mg L(-1), pH = 6.4-6.8, T = 20 degrees C, NH3 = 26 mg L(-1), PO4(3-) = 8.5 mg L(-1) . In treatment plant, the parameters such as BOD5, NH3, PO4(3-), SS, MLVSS, pH, temperature, sludge volume and microorganisms predominance are studied, under constant sedimentation time (30 min) against variable aeration times . As a second step, the same parameters are studied under the constant aeration time (4 h) against variable sedimentation times . Effluent concentrations from sequencing batch reactor (SBR) are determined BOD5 = 13-18 mg L(-1), COD = 25-37 mg L(-1), SS= 9-21 mg L(-1), pH = 7.3-7.6, TDF = 1-2, T = 23 degrees C, NH3 = 1 mg L(-1), PO4(3-) = 8.1 mg L(-1) . At the end of 6 h of aeration time, the efficiency of BOD5 reaches to 83% . The efficiency of BOD5 reaches to 81% under a 4 h aeration time and at 90 min sedimentation time . As a result, the optimum treatment efficiency has been taken under 4 h of aeration time and of 60 min of sedimentation time. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2069 - 76 A dynamic model for anaerobic filter; Cakir FY et al.; Anaerobic filters are frequently used to treat medium to high strength wastewater (2000-20000 mg/L COD), but have fewer applications to low strength wastewater (< 1000 mg/L COD) . In order to understand the applicability of anaerobic treatment for low strength wastewater, such as domestic sewage, a dynamic mathematical model was developed . This Monod-type kinetic model, which predicts treatment efficiency and gas production, was used to describe literature observations and is offered as a predictive tool. J Environ Sci Health A Tox Hazard Subst Environ Eng, 2003, 38(10), 2019 - 28 Degradation of organic substances and reactive dye in an immobilized-cell sequencing batch reactor operation on simulated textile wastewater; Pasukphun N et al.; Textile wastewater generally consists of high organic substances and is strongly colored . Reactive dye has been used extensively in the textile industries . It is water soluble and difficult to remove by chemical coagulation . Removal of organic substances simultaneously with dye can be achieved by a biological process . This study aims to investigate the treatability of the organic substances and reactive dye in immobilized-cell sequencing batch reactors (SBR) . Three different supporting medias namely activated carbon, steel slag and plastic were used . The performance of each reactor was compared with a conventional sequencing batch reactor . The simulated textile wastewater containing the reactive azo dye Procion Red H-E7B of a concentration of 40 mg/L and COD 300 mg/L, was fed into the reactors . The supporting media in the SBR system, it will enhance the capability of COD and dye operating of the SBRs consisted of 5 periods; Fill 1.5 h, React (anoxic:oxic) 20 (14:6) h, Settle 1.5 h, Draw 0.5 h and Idle 0.5 h . The results revealed that by adding removal . During a steady state of operation, the COD and dye concentrations of each period were investigated . In addition, the prolonged anoxic period brought about better decolorization efficiency. Environ Sci Technol, 2003 Sep 15, 37(18), 4281 - 7 Co-removal of hexavalent chromium through copper precipitation in synthetic wastewater; Sun JM et al.; The mechanisms of hexavalent chromium {Cr(VI)} co-removal with copper {Cu(II)} during homogeneous precipitation were studied with batch tests using a synthetic solution containing Cr(VI) and Cu(II) . Metal precipitation was induced by adding Na2CO3 stepwise to different pH, and the respective removals of Cu(II) and Cr(VI) were measured . At the same time, the relative quantities of Cu(II) and Cr(VI) in the precipitates were also analyzed to establish their stoichiometric relationship . The results indicated that, in a solution containing 150 mg/L Cu(II) and 60 mg/L Cr(VI), the initial co-removal of Cr(VII with Cu(II) began at pH 5.0 and completed at pH 6.2 . At pH 5.0-5.2, coprecipitation took place through the formation of copper-chromium-bearing solids {such as CuCrO4 and/or CuCrO4 x 2Cu(OH)2} . Thereafter, the remaining soluble copper started to react with carbonate in a heterogeneous environment to form the negatively charged basic copper carbonate precipitates {CuCO3 x Cu(OH)2}, which subsequently adsorbed additional Cr(VI) (or HCrO4-) at pH 5.2-6.2 . The maximum Cr(VI) co-removal took place at pH 6.2 . Between the two mechanisms, co-precipitation accounted for about 29% of the total chromium's co-removal while the remaining 71% was attributed to surface adsorption, mainly through electrostatic attraction and ligand exchange . When the solution pH was increased to beyond 7.5, a surface charge reversal took place on the basic copper carbonate solids, and this led to some Cr(VI) desorption . Thus, the extent of Cr(VI) adsorption is highly pH dependent. Environ Sci Technol, 2003 Sep 15, 37(18), 4269 - 73 Use of copper shavings to remove mercury from contaminated groundwater or wastewater by amalgamation; Huttenloch P et al.; The efficacy of copper shavings (Cu(0)) for the removal of Hg2+ from aqueous solution by amalgamation is demonstrated . Two kinds of copper shavings were investigated: (a) chemically processed shavings (Fluka) and (b) recycled shavings from scrap metal . Batch sorption experiments yielded very high retardation coefficients of 28 850-82 830 for the concentration range studied (1-10 000 microg/L Hg2+ dissolved in distilled water or in a 0.01 M CaCl2 matrix solution) . Sorption data were well-described bythe Freundlich isotherm equation . Kinetic batch sorption experiments showed that 96-98% of Hg2+ was removed within 2 h . Column experiments were performed with a mercury solution containing 1000 microg/L Hg in a 0.01 M CaCl2 matrix with a flow rate of 0.5 m/d . No mercury breakthrough (c/c(0) = 0.5) could be detected after more than 2300 percolated pore volumes, and the high retardation coefficients determined in the batch studies could be confirmed . Copper was released from the shavings due to the amalgamation process and to copper corrosion by oxygen, resulting in concentrations of mobilized copper of 0.2-0.6 mg/L . Due to their high efficiency in removing Hg2+ from aqueous solution, the use of copper shavings for the removal of mercury from contaminated water is suggested, employing a sequential system of mercury amalgamation followed by the removal of mobilized copper by an ion exchanger such as zeolites . Possible applications could be in environmental technologies such as wastewater treatment or permeable reactive barriers for in situ groundwater remediation. Waste Manag, 2003, 23(8), 709 - 17 Technical assessment of fuel cell operation on anaerobic digester gas at the Yonkers, NY, wastewater treatment plant; Spiegel RJ et al.; This paper summarizes the results of a 2-year field test to assess the performance of a specially modified commercial phosphoric acid 200-kW fuel cell power plant to recover energy from anaerobic digester gas (ADG) which has been cleansed of contaminants (sulfur and halide compounds) using a patented gas pretreatment unit (GPU) . Specific project goals include characterization of the fuel cell power plant emissions and verification of the GPU performance for removing sulfur contaminants . To remove halide contaminants from the ADG, a halide guard, consisting of a vessel with a metal oxide supported on alumina, was incorporated into the fuel cell reactant supply . This first-of-a-kind demonstration was conducted at the Yonkers, NY, wastewater treatment plant, a sewage processing facility owned and operated by Westchester County . Results have demonstrated that the ADG fuel cell power plant can produce electrical output levels close to full power (200 kW) with negligible air emissions of CO, NO(x), and SO(2) . The GPU removed virtually 100% of H(2)S and 88% of organic sulfur, bringing the overall sulfur removal efficiency of the GPU to over 99% . The halide guard