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Sewage Treatment Plants (sewage + treatment_plant)
Selected AbstractsImpact of five selected xenobiotics on isolated ammonium oxidizers and on nitrifying activated sludgeENVIRONMENTAL TOXICOLOGY, Issue 4 2006S. N. Dokianakis Abstract Sewage treatment plants (STPs) are usual receptors of xenobiotic compounds that have to be cotreated with municipal wastewaters before being discharged to the water environment. The presence of organic contaminants, such as surfactants, polycyclic aromatic hydrocarbons (PAHs), phthalates, and their primary degradation products in the influents of STPs may inhibit irreversibly sensitive biological processes, such as nitrification. The first step of nitrification, i.e., the oxidation of ammonium to nitrite (nitritification), is particularly sensitive. Inhibition of this step under uncontrolled conditions may completely inhibit biological nitrogen removal. The aim of this work was to study the possible inhibitory effect of five selected xenobiotics on (a) a mixed culture of ammonium-oxidizing bacteria isolated from activated sludge and (b) nitrifying activated sludge directly. The xenobiotics that were tested include nonylphenols (NP), nonylphenolethoxylates (NPEO), linear alkylbenzene sulfonates (LAS), di(2-ethylhexyl) phthalate (DEHP), as a representative phthalate ester, and the PAH phenanthrene. Remarkable inhibitory effects for all tested compounds were observed in this study even at xenobiotic concentrations as low as 1 mg/L. The observed inhibition of xenobiotics on nitrifying activated sludge was less pronounced, because of the masking effect exerted by the sludge flocs, but was still significant for many of the tested substances at concentrations up to 10 mg/L. © 2006 Wiley Periodicals, Inc. Environ Toxicol 21: 310,316, 2006. [source] Seasonality effects on pharmaceuticals and s -triazine herbicides in wastewater effluent and surface water from the Canadian side of the upper Detroit RiverENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2006Wen Yi Hua Abstract The influence of seasonal changes in water conditions and parameters on several major pharmacologically active compounds (PhACs) and s -triazine herbicides was assessed in the wastewater and sewage treatment plant (WSTP) effluent as well as the downstream surface water from sites on the Canadian side of the upper Detroit River, between the Little River WSTP and near the water intake of a major drinking water treatment facility for the City of Windsor (ON, Canada). The assessed PhACs were of neutral (carbamazepine, cotinine, caffeine, cyclophosphamide, fluoxetine, norfluoxetine, pentoxifylline, and trimethoprim) and acidic (ibuprofen, bezafibrate, clofibric acid, diclofenac, fenoprofen, gemfibrozil, indomethacin, naproxen, and ketoprofen) varieties. The major assessed s -triazine herbicides were atrazine, simazine, propazine, prometon, ametryn, prometryn, and terbutryn. At sampling times from September 2002 to June 2003, 15 PhACs were detected in the WSTP effluent at concentrations ranging from 1.7 to 1,244 ng/L. The PhAC concentrations decreased by as much 92 to 100% at the Little River/Detroit River confluence because of the river dilution effect, with further continual decreases at sites downstream from the WSTP. The only quantifiable s -triazine in WSTP effluent, atrazine, ranged from 6.7 to 200 ng/L and was higher in Detroit River surface waters than in WSTP effluent. Only carbamazepine, cotinine, and atrazine were detectable at the low-nanogram and subnanogram levels in surface waters near a drinking water intake site. Unlike the PhACs, atrazine in the Detroit River is not attributable to point sources, and it is heavily influenced by seasonal agricultural usage and runoff. Detroit River surface water concentrations of carbamazepine, cotinine, and atrazine may present a health concern to aquatic wildlife and to humans via the consumption of drinking water. [source] Evaluation of the ishikawa cell line bioassay for the detection of estrogenic substances from sediment extractsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2005Shinya Hashimoto Abstract This study examines the application of Ishikawa human endometrial adenocarcinoma cells to measure the estrogenic activity of fractionated extracts of sediments from Tokyo Bay, Japan. Estrogen stimulates alkaline phosphatase activity in this cell line. The results of these assays were compared with those of a yeast estrogen screen (YES) assay. The Ishikawa cell line bioassay showed higher sensitivity to 17,-estradiol (median effective concentration [EC50], 10.7 pM) than did the YES assay (EC50, 480 pM). Fractionation of sediment extracts (all samples collected from 5 sites) showed that the nonpolar fraction was poisonous to yeast cells; the estrogenic activity of this fraction, therefore, could not be measured by YES. However, the nonpolar fraction did not kill the Ishikawa cells. The 17,-estradiol-equivalent values of 15 extracts (3 fractions from each of 5 sediment samples) ranged from 5.7 to 697 pg/g dry weight according to the Ishikawa cell line bioassay. Chemical analysis using gas chromatography-mass spectrometry revealed that the highest concentrations of endocrine-disrupting chemicals were observed at the sampling station near the sewage treatment plant. The results support that the Ishikawa cell line bioassay is suitable for measuring the estrogenic activity of sediment samples. [source] Identification of chlorfenvinphos toxicity in a municipal effluent in Sydney, New South Wales, AustraliaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2005Howard C. Bailey Abstract Acute toxicity in a municipal sewage treatment plant in Sydney, New South Wales, Australia, was traced to chlorfenvinphos, an organophosphorous pesticide. Toxicity identification evaluation procedures led to the tentative identification of chlorfenvinphos as the toxic contaminant in the sample. Subsequent analytical verification revealed 0.95 ,g/L of chlorfenvinphos in the effluent sample, and spiking studies confirmed that it accounted for the observed toxicity. The 48-h median lethal concentration of chlorfenvinphos to Ceriodaphnia dubia averaged 0.28 ,g/L (n = 4). Source-control measures were effective at eliminating chlorfenvinphos and associated toxicity from the discharge. [source] Development of a fish reporter gene system for the assessment of estrogenic compounds and sewage treatment plant effluentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2002Gabriele E. Ackermann Abstract This study reports on the development and application of a fish-specific estrogen-responsive reporter gene assay. The assay is based on the rainbow trout (Oncorhynchus mykiss) gonad cell line RTG-2 in which an acute estrogenic response is created by cotransfecting cultures with an expression vector containing rainbow trout estrogen receptor a complementary DNA (rtER, cDNA) in the presence of an estrogen-dependent reporter plasmid and an estrogen receptor (ER) agonist. In a further approach, RTG-2 cells were stably transfected with the rtER, cDNA expression vector, and clones responsive to 17,-estradiol (E2) were selected. The estrogenic activity of E2, 17,-ethinylestradiol, 4-nonylphenol, nonylphenoxy acetic acid, 4- tert -octylphenol, bisphenol A, o,p,-DDT, p,p,-DDT, o,p,-2,2-bis(chlorophenyl)-1,1-dichloroethylene (o,p,-DDE), p,p,-DDE, o,p,-2,2-bis(chlorophenyl)-1,1-di-chloroethane (o,p,-DDD), p,p,-DDD, and p,p,-2,2-bis(chlorophenyl)acetic acid (p,p,-DDA) was assessed at increasing concentrations. All compounds except o,p,-DDT, p,p,-DDE, and p,p,-DDA showed logistic dose-response curves, which allowed the calculation of lowest-observed-effect concentrations and the concentrations at which half-maximal reporter gene activities were reached. To check whether estrogen-responsive RTG-2 cells may be used to detect the estrogenic activity of environmental samples, an extract from a sewage treatment plant (STP) effluent was assessed and found to have estrogenic activity corresponding to the transcriptional activity elicited by 0.05 nM of E2. Dose-response curves of nonylphenol, octylphenol, bisphenol A, and o,p,-DDD revealed that the RTG-2 reporter gene assay is more sensitive for these compounds when compared to transfection systems recombinant for mammalian ERs. These differences may have an effect on the calculation of E2 equivalents when estrogenic mixtures of known constitution, or environmental samples, such as STP effluents, are assessed. [source] Biodegradation and transport of benzene, toluene, and xylenes in a simulated aquifer: comparison of modelled and experimental resultsHYDROLOGICAL PROCESSES, Issue 16 2002Jiin-Shuh Jean Abstract Both laboratory experiments and numerical modelling were conducted to study the biodegradation and transport of benzene,toluene,xylenes (BTX) in a simulated semi-confined aquifer. The factors incorporated into the numerical model include advection, hydrodynamic dispersion, adsorption, and biodegradation. The various physico-chemical parameters required by the numerical model were measured experimentally. In the experimental portion of the study, BTX compounds were introduced into the aquifer sand. After the contaminants had been transported through the system, BTX concentrations were measured at 12 equally spaced wells. Subsequently, microorganisms obtained from the activated sludge of a sewage treatment plant and cultured in BTX mixtures were introduced into the aquifer through the 12 sampling wells. The distribution data for BTX adsorption by the aquifer sand form a nonlinear isotherm. The degree of adsorption by the sand varies, depending on the composition of the solute. The degradation time, measured from the time since the bacteria were added to the aquifer until a specific contaminant was no longer detectable, was 35,42 h for BTX. The dissolved oxygen, after degradation by BTX compounds and bacteria, was consumed by about 40,60% in the entire simulated aquifer; thus the aerobic conditions were maintained. This study provides insights for the biodegradation and transport of BTX in aquifers by numerical modelling and laboratory experiments. Experimental and numerical comparisons indicate that the results by Monod degradation kinetics are more accurate than those by the first-order degradation kinetics. Copyright © 2002 John Wiley & Sons, Ltd. [source] Peracetic acid as an alternative wastewater disinfectant to chlorine dioxideJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002S. Stampi Aims: The aim of this study was to compare the efficiency of peracetic acid with that of chlorine dioxide in the disinfection of wastewater from a sewage treatment plant (serving about 650 000 inhabitants) that has been using peracetic acid as a disinfectant since 1998. Methods and Results: A total of 23 samplings were made, each consisting of three samples: from secondary effluent, effluent disinfected with 2 mg l,1 of peracetic acid and effluent disinfected with 2·2 mg l,1 of chlorine dioxide (contact time 20 min). For each sample, measurements were made of the heterotrophic plate count at 36°C, total and faecal coliforms, Escherichia coli, enterococci, pH, suspended solids and chemical oxygen demand (COD). During the first phase of the experiment the peracetic acid was seen to be less efficient than chlorine dioxide. To improve the disinfectant action a system of mechanical agitation was added which led to a greater efficiency in the inactivation of bacteria of faecal origin. Conclusions: Both products were found to be influenced by the level of microbial contamination, the amount of suspended solids and COD but not by the pH of the effluent before disinfection. The immediate mixing of the wastewater and disinfectant caused a greater reduction in enterococci. Significance and Impact of the Study: Since peracetic acid was seen to produce a high abatement of micro-organisms, it can be considered as a valid alternative to chlorine dioxide in the disinfection of wastewaters. [source] Life-Cycle Assessment of Biosolids Processing OptionsJOURNAL OF INDUSTRIAL ECOLOGY, Issue 2 2001Gregory M. Peters Summary Biosolids, also known as sewage sludge, are reusable organic materials separated from sewage during treatment. They can be managed in a variety of ways. Different options for biosolids handling in Sydney, Australia, are compared in this study using life-cycle assessment. Two key comparisons are made: of system scenarios (scenario 1 is local dewatering and lime amendment; scenario 2 is a centralized drying system) and of technologies (thermal drying versus lime amendment). The environmental issues addressed are energy consumption, global warming potential (GWP), and human toxicity potential (HTP). Scenario 2 would consume 24% more energy than scenario 1. This is due to the additional electricity for pumping and particularly the petrochemical methane that supplements biogas in the drier. A centralized system using the same technologies as scenario 1 has approximately the same impacts. The GWP and HTP of the different scenarios do not differ significantly. The assessment of technology choices shows significant differences. The ample supply of endogenous biogas at North Head sewage treatment plant for the drying option allows reductions, relative to the lime-amendment option, of 68% in energy consumption, 45% in GWP, and 23% in HTP. Technology choices have more significant influence on the environmental profile of biosolids processing than does the choice of system configurations. Controlling variables for environmental improvement are the selection of biogas fuel, avoidance of coalsourced electrical energy, minimization of trucking distances, and raising the solids content of biosolids products. [source] Correlation between rotavirus A genotypes detected in hospitalized children and sewage samples in 2006, Córdoba, ArgentinaJOURNAL OF MEDICAL VIROLOGY, Issue 7 2010P.A. Barril Abstract Routine rotavirus A (RV-A) surveillance is based on clinical cases, so only symptomatic infections are reported. The objective of this study was to determine whether the RV-A genotypes and cold seasonal pattern described in patients with diarrhea is reflected by sewage surveillance, which could be representative of the RV-A genotypes circulating in the population. The genotype distribution of RV-A in effluent samples from a local sewage treatment plant was compared to those from local clinical cases. A total of 52 sewage samples and 70 stool specimens from children with acute non-bacterial diarrhea were collected from January to December 2006. The effluent specimens were concentrated and RNA extracts from concentrated sewage and clinical samples were genotyped for the rotavirus VP7 gene. The proportional distribution of the RV-A G-genotypes in sewage and clinical samples during the cold season was similar: G1 accounted for 26.6% of the typed sewage isolates and 28.8% of the clinical infections; G3 type accounted for 21.9% and 25.8%; G2 type 15.6% and 10.6%; G4 type 17.2% and 21.2%; G8 type 1.6% and 0%; and the G9 type 17.2% and 13.6%, respectively. A similar picture of RV-A genotype detection was obtained in sewage samples collected during the cold and warm seasons. The results indicate that there is a correlation between genotypes of RV-A isolates from human diarrheic patients and of those from sewage samples. In addition, sewage monitoring highlighted the uniform all-year RV-A circulation, which was in contrast to the peak incidence of RV-A infection in the community. J. Med. Virol. 82: 1277,1281, 2010. © 2010 Wiley-Liss, Inc. [source] Detection of extended-spectrum ,-lactamase-producing Klebsiella pneumoniae in effluents and sludge of a hospital sewage treatment plantLETTERS IN APPLIED MICROBIOLOGY, Issue 1 2008T. Prado Abstract Aims:, To detect ESBL (extended-spectrum ,-lactamase)-producing Klebsiella pneumoniae present in the effluents and sludge of a hospital sewage treatment plant, evaluating the treatment plant's potential to remove these micro-organisms. Methods and Results:, Twenty samples (crude sewage, UASB reactor effluent, filtered effluent and sludge) were collected in the period from May to December 2006, in order to analyse antimicrobial susceptibility and to check ESBL production, the disc-diffusion and the combined disc methods were used. Total and faecal coliform concentrations were also determined. ESBL-producing K. pneumoniae were detected in all samples analysed, representing 46·5% of the total strains isolated. Among the non-ESBL-producing strains, 26% were multiresistant and one strain resistant to eight of the nine antimicrobials tested was detected in the treated effluent. Conclusions:, The hospital wastewater treatment plant did not show a satisfactory efficacy in removing pathogenic micro-organisms, allowing for the dissemination of multiresistant bacteria into the environment. Significance and Impact of the Study:, The inefficacy of hospital wastewater treatment plants can result in routes of dissemination of multiresistant bacteria and their genes of resistance into the environment, thus contaminating water resources, and having serious negative impact on public health. [source] Occurrence of pharmaceuticals and hormones in sewage sludgeENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2010Antonio Nieto Abstract The present study evaluates the presence of nine hormones and their conjugates and 20 pharmaceuticals such as anti-inflammatories, lipid regulators, and antibiotics among others in sewage sludge from two sewage treatment plants (STPs) in the Tarragona area (Spain) for the period March 2007 until March 2008. Target analytes have been determined using different methods involving pressurized liquid extraction and liquid chromatography (electrospray ionization) tandem mass spectrometry (MS-MS). Most of the pharmaceuticals and hormones were found at low micrograms per kilogram dry weight levels in the sewage sludge samples analyzed. Some compounds were present in all samples, such as acetaminophen, caffeine, carbamazepine, and ibuprofen, among others. Other compounds, such as estriol, were found only in the STP of Reus. The compounds that showed the highest concentration in both STPs were roxithromycin and tylosin (1,446 and 1,958,µg/kg dry wt, respectively). The presence of these compounds in sewage sludge demonstrated that they are partially or totally removed from the influent wastewater by sorption into the sewage sludge. Environ. Toxicol. Chem. 2010;29:1484,1489. © 2010 SETAC [source] Identifying the nonpoint source of perfluorinated compounds using a geographic information system based approachENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2009Yasuyuki Zushi Abstract Perfluorinated compounds (PFCs) have been detected in a wide range of places. They have also been reported to come from nonpoint sources, but the origin of these sources has not been identified. In the present study, we attempted to characterize the nonpoint source of PFCs in the Hayabuchi River, Japan, which runs through an urban area, using a geographic information system (GIS) and statistical analysis. We also estimated annual PFC loads from nonpoint sources in Japan as a whole, determining a magnitude comparable to that from sewage treatment plants (STPs); the range was a few tons per year for each PFC. Perfluorinated compound pollution in river water was found to increase when the river received drainage from an area with a high proportion of commercial and/or transportation land use. It was also found that more PFCs were discharged from the watersheds where train stations are located. This result could be interpreted as the use of land for commercial and transportation purposes is prevalent in close proximity to train stations, and that the effluents from those areas contain high concentrations of PFCs. These findings suggested that train stations could be indicators of nonpoint sources of PFCs. [source] Modeling the environmental fate of perfluorooctanoate and its precursors from global fluorotelomer acrylate polymer useENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2008Rosalie van Zelm Abstract The environment contains various direct and indirect sources of perfluorooctanoic acid (PFOA). The present study uses a dynamic multispecies environmental fate model to analyze the potential formation of perfluorooctanoate (PFO), the anion of PFOA, in the environment from fluorotelomer acrylate polymer (FTacrylate) emitted to landfills and wastewater, residual fluorotelomer alcohol (8:2 FTOH) in FTacrylate, and residual PFOA in FTacrylate. A multispecies version of the SimpleBox model, which is capable of determining the fate of a chemical and its degradation products, was developed for this purpose. An uncertainty analysis on the chemical-specific input parameters was performed to examine for uncertainty in modeled concentrations. In 2005, residual 8:2 FTOH made up 80% of the total contribution of FTacrylate use to PFO concentrations in global oceans, and residual PFOA in FTacrylate contributed 15% to PFO concentrations from FTacrylate use in global oceans. After hundreds of years, however, the main source of PFO from total historical FTacrylate production is predicted to be FTacrylate degrading in soil following land application of sludge from sewage treatment plants, followed by FTacrylate still present in landfills. Uncertainty in modeled PFO concentrations was up to a factor of 3.3. Current FTacrylate use contributes less than 1% of the PFO in seawater, but because direct PFOA emission sources are reduced and PFOA continues to be formed from FTacrylate in soil and in landfills, this fraction grows over time. [source] Fate of estrogens and xenoestrogens in four sewage treatment plants with different technologies,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2008Guang-Guo Ying Abstract The fate and removal of the estrogens 17,-estradiol (E2), estrone (E1), and 17,-ethynylestradiol (EE2) and of the xenoestrogens bisphenol A (BPA), 4- tert -octylphenol (4- t -OP), 4-nonylphenol (4-NP), and nonylphenol mono- and diethoxylate (NPEO1 and NPEO2, respectively) were investigated in four South Australian sewage treatment plants (STPs; plants A,D) with different treatment technologies. The concentrations in the effluent from the two-year survey were similar to those reported in other studies. In the effluent, 4-NP, NPEO1, and NPEO2 had total concentrations up to 8 ,g/L, which were much higher than those of BPA and 4-t-OP. Estrone had the highest concentrations among the three estrogens, ranging between 13.3 and 39.3 ng/L, whereas the concentrations for E2 and EE2 varied between 1.0 and 4.2 ng/L and between 0.1 and 1.3 ng/L, respectively. The removal rates for the estrogens and xenoestrogens were variable but consistent with the plant performance parameters (biochemical oxygen demand, suspended solids, and ammonia). Considering all the estrogenic compounds analyzed in the present study, plant D, with a series of anaerobic and aerobic lagoons, was the least efficient of the four STPs in the removal of these compounds. The removal rates for 4-NP, NPEO1, and NPEO2 within the plants were 92% for plant A, with conventional activated sludge treatment; 80% for plant B, with two oxidation ditches; 70% for plant C, with three bioreactors; and 64% for plant D, with 10 lagoons in series. Comparatively, the removal of estrogens was lower, with rates ranging between 47 and 68% for E2 at the four plants. Both E1 and EE2 were more persistent during treatment, especially in plants C and D. [source] Estrogenicity in bile of juvenile rainbow trout as measure of exposure and potential effects of endocrine disruptorsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2004Ann-Sofie Allard Abstract Estrogenicity in the bile of juvenile rainbow trout exposed to effluents from municipal sewage treatment plants and various industries was assayed by using a recombinant yeast strain containing the human estrogen receptor , gene. Estrogenicity in bile also was measured after deconjugation of steroids to provide an estimate of the exposure and as an endpoint for potential effects on the organism. In unexposed fish or fish exposed for three weeks at control localities, 0.5 to 9 ng of estradiol equivalents (EEq) were found per gram of bile (ng EEq/g bile). Fish exposed for three weeks in cages placed in the receiving waters near outlets of municipal effluent had an average activity of 26 ng EEq/g bile. Fish exposed to undiluted sewage water in aquaria had a bile estrogenicity of 51 to 87,000 ng EEq/g bile. Unconjugated estrogens contributed only 8% or less to the estrogenicity in bile of fish exposed to municipal effluents. Municipal sewage effluents were more estrogenic than the industrial effluents that were investigated. Estrogenicity in bile was compared to that in extracts of wastewater by using the same receptor assay, and to vitellogenin induction in the plasma of the same fish. Bile estrogenicity proved to be a useful and sensitive (internal) measure of exposure and indicated its potential for the display of biological effects as a complement or replacement of more laborious assays. [source] Substances with estrogenic activity in effluents of sewage treatment plants in southwestern Germany.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2001Abstract A gas chromatography/mass spectrometry method for the simultaneous quantitative determination of natural and synthetic estrogens (17,-estradiol, estrone, 17,-ethinylestradiol, and mestranol), phytoestrogens (genistein and ,-sitosterol), and xenoestrogens (benzyl butyl phthalate, dibutyl phthalate, bisphenol A, 4-nonylphenol [NP], 4-nonylphenoxyacetic acid [NP1EC], 4-nonyl-phenol diethoxylate [NP2EO], and ,-endosulfan) in effluents of sewage treatment plants (STPs) was developed. Identification and quantification were carried out with the standard addition method using analyte-specific and, in some cases, deuterium-labeled internal standards. The effluents of 18 STPs were investigated. Apart from ,-endosulfan and mestranol, all selected substances were detected in the majority of samples. The median concentrations of steroidal estrogens were between 0.4 ng/L (17,-ethiny-lestradiol) and 1.6 ng/L (17,-estradiol). The metabolites of the nonylphenol polyethoxylates, NP, NP1EC, and NP2EO were found in concentrations ranging from the upper-ng/L-range (NP) to the lower-,g/L range (NP1EC). For all substances except mestranol and ,-endosulfan, median values were calculated and compared to the results of other investigations in Europe and the United States. Possible dependencies of measured concentrations on the geographical location, the capacity, the influent composition, and the technical fitting of the STPs are discussed. [source] Substances with estrogenic activity in effluents of sewage treatment plants in southwestern Germany.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2001Abstract The proliferation test with human estrogen receptor-positive MCF-7 breast cancer cells (E-Screen assay) was applied for quantitative determination of total estrogenic activity in 24-h composite effluent samples from 16 municipal and two industrial sewage treatment plants (STPs) in the state of Baden-Württemberg, southwestern Germany. The estrogenic efficacy relative to the positive control, 17,-estradiol, was between 26 and 74% (median, 48%) for the 16 municipal STPs. Estradiol equivalent concentrations (EEQs) were between 0.2 and 7.8 ng/L (median, 1.6 ng/L) and, thereby, were lower than those found in a pilot study, which revealed EEQs of greater than 10 ng/L in the effluents of two other STPs. The EEQs in 14 of the 16 effluent samples were very similar (0.9,3.3 ng/L), indicating a rather constant input of estrogenic substances via STPs into rivers. Additional activated charcoal filtration turned out to be very efficient in further eliminating estrogenic activity from effluents. The EEQs of the E-Screen assay and those calculated from the results of extensive chemical analysis using the estradiol equivalency factors determined for 13 natural and synthetic estrogenic substances were comparable for most of the effluent samples. 17,-Estradiol, 17,-ethinylestradiol, and, to a lesser extent, estrone contributed to 90% or more of the EEQ value. [source] Distribution of degradation products of alkylphenol ethoxylates near sewage treatment plants in the lower Great Lakes, North AmericaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2000Erin R. Bennett Abstract Degradation of alkylphenol ethoxylate (APEO) surfactants in the environment leads to the formation of relatively hydrophobic compounds such as nonylphenol (NP), octylphenol (OP), nonylphenol monoethoxylate (NP1EO), and nonylphenol diethoxylate (NP2EO) that have been shown to have estrogenic activity. Previous studies have shown that sewage treatment plants (STPs) are point sources for these compounds in the aquatic environment. We collected sediment samples at several sites in the vicinity of STPs in Hamilton Harbour and in the Detroit River to determine the spatial distribution of the degradation products of APEOs. In addition, we deployed semipermeable membrane devices (SPMDs) and caged freshwater mussels (Elliptio complanata) at these locations to determine the distribution of these compounds in the dissolved phase and their potential to bioaccumulate in aquatic organisms. The NP, OP, NP1EO, and NP2EO were found at ,g/g (dry wt.) concentrations in sediments and accumulated to ng/g (wet wt.) concentrations in caged mussels near the STPs. However, in the Detroit River, the concentrations of these compounds declined to near background levels in the sediments, water column (i.e., SPMDs), and biota at stations about 1 km downstream from STPs. At stations in Hamilton Harbour, concentrations of APEO degradation products also declined markedly in sediments and SPMDs located a few hundred meters from the STP. These data indicate that degradation products of APEOs can be accumulated by biota near STPs. However, the environmental distribution of these compounds is localized to areas close to the point of discharge. [source] Nonylphenols in sediments and effluents associated with diverse wastewater outfalls,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2000Robert C. Hale Abstract Nonylphenols (NPs) have been reported to disrupt endocrine function and sexual development in aquatic organisms at low concentrations. Environmental NP burdens are predominantly derived from degradation of nonylphenol polyethoxylate surfactants. We detected NPs in discharge-associated riverine sediments adjacent to 11 of 20 active sewage treatment plants (STPs) at concentrations up to 12,400 ,g/kg. While most previous studies have focused on STPs, nonylphenols were observed in association with a variety of outfall types. The highest sediment burden, 14,100 ,g/kg, was detected near a federal facility's stormwater discharge. Of 75 sediments examined from 67 sites, 45% contained NP concentrations >5 ,g/kg; median concentration in these NP-positive sediments was 369 ,g/kg. Other surfactant-derived alkylphenolic compounds, specifically 4- tert -octylphenol and 4-cumylphenol, were observed in two sediments at 8,220 and 70,000 ,g/kg, respectively. The maximum NP concentration detected in an effluent, 6,300 ,g/L, was from a shipyard oil/water separator. Nonylphenols were detected (> 1.0 ,g/L) in 20% of the 59 effluents examined; 10% exceeded 10 ,g/L. Sediments sampled near a STP that had ceased treatment operations 20 years prior contained 54,000 ,g/kg, indicative of long-term NP residence. Results indicate that NPs may be released from diverse sources, concentrate in associated sediments, and persist therein for extended periods. [source] Heteroduplex mobility assay for the identification of Listeria sp. and Listeria monocytogenes strains: application to characterisation of strains from sludge and food samplesFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2003N Garrec Abstract One hundred and ten Listeria sp. isolates from sewage sludge were identified according to phenotypic and genotypic methods. The Listeria sp. strains isolated from five types of sludge from three sewage treatment plants in Angers (France) and the surrounding area included L. monocytogenes (55.5%), L. innocua (29.1%), L. seeligeri (13.6%) and L. welshimeri (1.8%). The majority of L. monocytogenes strains belonged to serotypes 4b, 1/2b and 1/2a. Moreover, a heteroduplex mobility assay based on the 16S rRNA sequences was tested for its ability to identify the six species of the genus Listeria. This study, performed on 283 Listeria sp. strains from human, food and sewage sludge samples, showed that all the species were distinguishable from one another. L. innocua and L. seeligeri showed respectively three and two distinct banding patterns. Within L. monocytogenes, four groups (I,IV) were defined. The majority of food and environmental isolates were clustered in group I and it is noteworthy that group IV clustered epidemiologic isolates and strains belonging to serotypes 4b, 1/2a and 1/2b. [source] Occurrence of Cryptosporidium spp. oocysts in raw and treated sewage and river water in north-eastern SpainJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2005M. Montemayor Abstract Aims:, To determine the occurrence and levels of Cryptosporidium parvum oocysts in wastewater and surface waters in north-eastern Spain. Methods and Results:, Samples from five sewage treatment plants were taken monthly and quarterly during 2003. In addition, water was collected monthly from the River Llobregat (NE Spain) during the period from 2001 to 2003. All samples were analysed by filtration on cellulose acetate filters or through EnvirocheckTM using EPA method 1623, followed by immunomagnetic separation and examination by laser scanning cytometry. All raw sewage, secondary effluent and river water samples tested were positive for Cryptosporidium oocysts. Of the tertiary sewage effluents tested, 71% were positive for Cryptosporidium oocysts. The proportion of viable oocysts varied according to the sample. Conclusions:, Two clear maxima were observed during spring and autumn in raw sewage, showing a seasonal distribution and a correlation with the number of cryptosporidiosis cases and rainfall events. Significance and Impact of the Study:, This study provides the first data on the occurrence of Cryptosporidium oocysts in natural waters in north-eastern Spain. [source] Increased incidence of saprophytic bacteria, coliforms and E. coli following severe flooding requires risk assessment for human health: results of the River Elbe flood in August 2002JOURNAL OF FLOOD RISK MANAGEMENT, Issue 1 2009B. Karrasch Abstract In August 2002, flooding in the Elbe valley caused severe damage of sewage treatment plants and networks. We investigated the impact of flooding on the bacteriological water quality (colony-forming units of saprophytic bacteria, coliform bacteria and Escherichia coli) compared with levels from previous and subsequent years. The flood introduced organic matter and elevated saprophytic bacteria levels, and a general increase of coliform bacteria. Markedly high loads of coliforms and E. coli were detected in the water column in areas where damage to sewage treatment plants was rife, exceeding the European Commission's Bathing Water Directive. The rapid disappearance from the water column may partly be caused by sedimentation creating deposits on pasture, farmland and in built-up areas, which could represent a health hazard. Future flood risk reduction should therefore be focused on the protection of sewage systems and hygienic monitoring of floodwater and flood sediments. [source] Molecularly imprinted polymer for selective extraction of endocrine disrupters nonylphenol and its ethoxylated derivates from environmental solidsJOURNAL OF SEPARATION SCIENCE, JSS, Issue 13 2008Laura Núñez Abstract Nonylphenol isomers (NP), linear nonylphenol (4-n-NP) and NP short chain ethoxylated derivates (NPEO1 and NPEO2) are degradation products of nonylphenol polyethoxylates, a worldwide used group of surfactants. All of them are considered endocrine disrupters due to their ability to mimic natural estrogens. In this paper, the preparation and evaluation of several 4-n-NP molecularly imprinted polymers (MIPs) for the selective extraction and clean-up of 4-n-NP, NP, NPEO1 and NPEO2 from complex environmental solid samples is described. Among the different combinations tested, a methacrylic acid-based imprinted polymer prepared in toluene provided the better performance for molecularly imprinted SPE (MISPE). Under optimum MISPE conditions, the polymer was able to selectively retain not only linear NP but also the endocrine disruptors NPEO1, NPEO2 and NP with recoveries ranging from 60 to 100%, depending upon the analyte. The developed MISPE procedure was successfully used for the determination of 4-n-NP, NP, NPEO1 and NPEO2 in sediments and sludge samples at concentration levels according to data reported in the literature for incurred samples. Finally, various sludge samples collected at five different sewage treatment plants from Madrid and commercial sludge for agriculture purposes were analysed. The measured concentrations of the different compounds varied from 3.7 to 107.5 mg/kg depending upon the analyte and the sample. [source] GC-MS analysis of organic compounds in wastewater and sewage sludgeJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1 2008Axel Patrick Ligon Abstract A multimethod based on liquid,liquid extraction and solid,liquid extraction for the analysis of persistent organic pollutants in water and sludge from sewage treatment plants has been established. Traces of 22 organic compounds used in industry and personal care products (PCPs) were analyzed by GC/MS. The LODs for the analytes were less than 2.3 ng/L for wastewater and 31 ,g/kg (dry weight matter) for sewage sludge. Satisfactory recoveries (70,130%) were achieved. The validated method permits the analysis of water and sludge samples at various stages of the treatment from different sewage treatment plants. Thus, the distribution between water and sludge as well as the dissipation of the compounds analyzed were balanced. By this means, the efficiency of different wastewater treatment plants (WWTPs) can be evaluated and measures can be taken to optimize the treatment process at different stages. [source] Partition of metals in the Vistula River and in effluents from sewage treatment plants in the region of Cracow (Poland)LAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 2 2000C. Guéguen Abstract The Vistula River suffers from heavy pollution with multiple origins. In the upper reaches, metallic and chlorine pollution originates from the mining and industrial region of Upper Silesia. Downstream from Upper Silesia, urban and industrial sewage adds more metallic and organic contaminants from the large urban agglomeration of Cracow. Although the river status is monitored routinely, little is known about the partition of metals between particulate and dissolved forms. This study focuses on metal partitioning and on the impact of the two main wastewater treatment plants at Cracow on metal concentrations in the Vistula River. The Cd, Co, Cu, Mn, Pb and Zn content was measured in both dissolved and particulate fractions. High metal concentrations in the Vistula River persist, although current levels seem to be lower than those in the past. Metal concentrations in the Vistula River and effluents from the sewage treatment plants at Cracow are similar, indicating a relatively minor contribution from the treated sewage. However, untreated sewage may be a significant source of contaminants. Despite high anthropogenic metal concentrations, the metal partitioning coefficients (Kd) in the Vistula are similar to these found in unpolluted rivers. Within a narrow pH range, Kd values depend on the metal affinity to particles, but there is no evidence of dependence on particle or chloride concentrations. An important fraction of the toxic metals Pb and Cd is associated with particles, which may decrease their immediate availability to the biota of the river. [source] Clonal groups of high-level gentamicin-resistant Enterococcus faecium isolated from municipal wastewater and clinical samples in Tehran, IranLETTERS IN APPLIED MICROBIOLOGY, Issue 2 2009M. Saifi Abstract Aims:, Clonality among high-level gentamicin-resistant Enterococcus faecium (HLGR-EF) isolates obtained from clinical and sewage treatment plants (STP) were investigated using PhePlate system (PhP), ribotyping and pulsed-field gel electrophoresis (PFGE). Methods and Results:, During 1 year study (September 2005,2006), a total of 106 HLGR-EF isolates were collected from clinical (n = 48) and STP (n = 58) samples in Tehran, Iran. Biochemical fingerprinting of these isolates using the PhP showed the presence of 21 PhP types (diversity index, Di = 0·97) among the clinical and 21 PhP types (Di = 0·91) among the STP isolates. Representative isolates of each PhP type (n = 42) were further characterized by the ribotyping method. Sixteen ribotypes were identified among the isolates with five types shared between the clinical and STP isolates. PFGE recognized 24 clonal types among these isolates with three pulsotypes shared between the clinical and STP isolates. Combination of the two techniques (PFGE and ribotyping) resulted in 24 (Di = 0·96) and 16 (Di = 0·93) types among the strains isolated from clinical and STP samples, respectively. Conclusions:, We concluded that the combination of PhP typing, ribotyping and PFGE could be extremely discriminatory when examining HLGR-EF isolates. Significance and Impact of the Study:, The emergence of highly diverse HLGR-EF population in Iran is of serious concern especially because of their multi-resistances. [source] | ||||||||||||||||