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Wastewater Effluent (wastewater + effluent)
Selected AbstractsReproductive health of bass in the Potomac, USA, drainage: Part 2.ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2009Seasonal occurrence of persistent, emerging organic contaminants Abstract The seasonal occurrence of organic contaminants, many of which are potential endocrine disruptors, entering the Potomac River, USA, watershed was investigated using a two-pronged approach during the fall of 2005 and spring of 2006. Passive samplers (semipermeable membrane device and polar organic chemical integrative sampler [POCIS]) were deployed in tandem at sites above and below wastewater treatment plant discharges within the watershed. Analysis of the samplers resulted in detection of 84 of 138 targeted chemicals. The agricultural pesticides atrazine and metolachlor had the greatest seasonal changes in water concentrations, with a 3.1- to 91-fold increase in the spring compared with the level in the previous fall. Coinciding with the elevated concentrations of atrazine in the spring were increasing concentrations of the atrazine degradation products desethylatrazine and desisopropylatrazine in the fall following spring and summer application of the parent compound. Other targeted chemicals (organochlorine pesticides, polycyclic aromatic hydrocarbons, and organic wastewater chemicals) did not indicate seasonal changes in occurrence or concentration; however, the overall concentrations and number of chemicals present were greater at the sites downstream of wastewater treatment plant discharges. Several fragrances and flame retardants were identified in these downstream sites, which are characteristic of wastewater effluent and human activities. The bioluminescent yeast estrogen screen in vitro assay of the POCIS extracts indicated the presence of chemicals that were capable of producing an estrogenic response at all sampling sites. [source] Dissolved fraction of standard laboratory cladoceran food alters toxicity of waterborne silver to Ceriodaphnia dubia,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2008Jason M. Kolts Abstract The biotic ligand model (BLM) for the acute toxicity of cationic metals to aquatic organisms incorporates the toxicity-modifying effects of dissolved organic matter (DOM), but the default parameterization (i.e., assuming 10% of DOM is humic acid) does not differentiate DOM from different sources. We exposed a cladoceran (Ceriodaphnia dubia) to Ag in the presence of DOM from filtered YCT (standard yeast,Cerophyll®,trout chow food recommended by the U.S. Environmental Protection Agency [EPA] for cladocerans), from the Suwannee River (GA, USA; relatively little anthropogenic input), and from the Desjardins Canal in Hamilton (ON, Canada; receives treated municipal wastewater effluent). In all three treatments, the dissolved organic carbon (DOC) concentration was 2 mg/L (the concentration following addition of YCT slurry at the U.S. EPA,recommended volume ratio). The average 48-h median effects concentration (EC50) ratios for dissolved Ag in the presence and absence of DOM [i.e., (EC50 with DOM)/(EC50 without DOM)] were as follows: Suwannee River, 1.6; Desjardins Canal, 2.2; and YCT filtrate, 26.8. Therefore, YCT filtrate provided much more protection against Ag toxicity than that provided by DOM from the surface waters. The major spectral characteristic that differentiated YCT filtrate from the other two types of DOM was a strong tryptophan peak in the excitation,emission matrix for YCT. These results have important implications for interpreting Ag toxicity tests in which organisms are fed YCT, and they suggest BLM-calculated toxicity predictions might be improved by incorporating specific chemical constituents or surrogate indices of DOM. Another component of the protective effect against Ag toxicity, however, might be that the dissolved fraction of YCT served as an energy and/or nutrient source for C. dubia. [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] A Geographic Information Systems,based, weights-of-evidence approach for diagnosing aquatic ecosystem impairmentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2006Katherine E. Kapo Abstract A Geographic Information Systems,based, watershed-level assessment using Bayesian weights of evidence (WOE) and weighted logistic regression (WLR) provides a method to determine and compare potential environmental stressors in lotic ecosystems and to create predictive models of general or species-specific biological impairment across numerous spatial scales based on limited existing sample data. The WOE/WLR technique used in the present study is a data-driven, probabilistic approach conceptualized in epidemiological research and both developed for and currently used in minerals exploration. Extrapolation of this methodology to a case-study watershed assessment of the Great and Little Miami watersheds (OH, USA) using archival data yielded baseline results consistent with previous assessments. The method additionally produced a quantitative determination of physical and chemical watershed stressor associations with biological impairment and a predicted comparative probability (i.e., favorability) of biological impairment at a spatial resolution of 0.5 km2 over the watershed study region. Habitat stressors showed the greatest spatial association with biological impairment in low-order streams (on average, 56% of total spatial association), whereas water chemistry, particularly that of wastewater effluent, was associated most strongly with biological impairment in high-order reaches (on average, 79% of total spatial association, 28% of which was attributed to effluent). Significant potential stressors varied by land-use and stream order as well as by species. This WOE/WLR method provides a highly useful "tier 1" watershed risk assessment product through the integration of various existing data sources, and it produces a clear visual communication of areas favorable for biological impairment and a quantitative ranking of candidate stressors and associated uncertainty. [source] Implication of polymer toxicity in a municipal wastewater effluentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2000Carolyn D. Rowland Abstract The use of cationic polymers as flocculants and coagulant aids to control suspended solid levels in the water and wastewater treatment industry is widespread in most developed countries. Today, the most frequently used clarification polymers, polyacrylamides, are often proprietary, and little information exists on the ecological impacts of these products. Following standard U.S. Environmental Protection Agency (U.S. EPA) whole effluent toxicity testing (WET) protocols, effluent toxicity can be detected via organism response, yet methods to positively characterize cationic polymers in effluents are not provided in U.S. EPA Phase I toxicity identification evaluation (TIE) protocols. Implication of cationic polymer toxicity in a municipal wastewater effluent was achieved through a series of Ceriodaphnia dubia toxicity testing with toxicant elimination steps that included extensive effluent characterization and effluent manipulation. Key in the identification was a discrepancy in effluent toxicity with respect to the type of container in which the effluents were stored. All effluent toxicity was lost within 48 h of storage in plastic containers, while on the contrary, effluent toxicity persisted in glass-contained samples for up to 4 weeks of 4°C storage. A weight-of-evidence approach suggested that the cationic polyacrilamide polymer, Hyperfloc®, was the primary source of acute toxicity in the effluent. Removal of this polymer significantly reduced effluent toxicity. This study suggests that cationic polymer-related toxicity might not be detected if effluent samples are stored in plastic containers. [source] Competition between two nitrite-oxidizing bacterial populations: a model for studying the impact of wastewater treatment plant discharge on nitrification in sedimentFEMS MICROBIOLOGY ECOLOGY, Issue 1 2002Christine Féray Abstract Nitrobacter, a ubiquitous nitrite oxidizer in natural and anthropized environments, is commonly studied as the model genus performing the second stage of nitrification. In rivers, wastewater treatment plant discharges may affect the nitrite-oxidizing activity and the responsible genera that are largely associated with sediment. We used a laboratory batch culture approach with Nitrobacter wynogradskyi ssp. agilis strain AG and Nitrobacter hamburgensis strain X14 to characterize the possible stress effect of wastewater effluent on these populations and to study the possible competition between an effluent strain (X14) and a sediment strain (AG) over a 42-day incubation time. Immunofluorescence enumerations of each strain showed that they both survived and settled in the sediment, indicating that there was no significant stress effect due to chemical changes caused by the effluent. The development of the strains' density and activity was directly correlated with the available nitrite concentration. Nevertheless, the potential specific activity was not constant along the so-called mixotrophic (non-limiting nitrite concentration) and heterotrophic (nitrite depletion) conditions. This illustrates the inducibility of the nitrite oxidoreductase and indicates the metabolic versatility of the strains. In our experimental conditions, the preferentially autotrophic AG strain appeared more competitive than the preferentially mixo- or heterotrophic X14 strain, including in heterotrophic environment. [source] Influence of a Trout Farm on Water Quality and Macrozoobenthos Communities of the Receiving Stream (Tre,njica River, Serbia)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 6 2009Ivana Abstract Trout farming is constantly increasing and poses a serious threat to water quality of clean highland streams. In the present work, we investigated the influence of the farm with the highest trout production in Serbia on water quality and macrozoobenthos communities of the receiving stream, the Tre,njica River. Our study revealed that changes of water chemistry parameters downstream from the trout farm were moderate and mainly confined to the part of the watercourse closest to the wastewater outlet. Moreover, use of food with 0.8% phosphorus content was sufficient to completely eliminate soluble phosphates from water samples of the Tre,njica River. However, the changes in water chemistry were sufficient to cause significant changes in the macrozoobenthos community. These changes remained statistically significant even 500 m downstream and were lost about 3.5 km from the trout farm wastewater effluent. The trout biomass on the farm is a parameter that adequately defines the magnitude of its impact, above all the intensity of its influence on the zoobenthos community structure. The most informative parameters for estimating that influence were the Baetidae/Ephemeroptera ratio, Margelef's index and the Modified biotic index. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Life-cycle exposure of fathead minnows (Pimephales promelas) to an ethinylestradiol concentration below 1 ng/L reduces egg fertilization success and demasculinizes malesENVIRONMENTAL TOXICOLOGY, Issue 2 2005Joanne L. Parrott Abstract Forty-eight hours after fertilization, fathead minnow (Pimephales promelas) eggs were exposed to the synthetic estrogen 17,-ethinylestradiol (EE2) at nominal concentrations of 0.32 and 0.96 ng/L and measured concentrations of 3.5, 9.6, and 23 ng/L. The fish were observed through the larval, juvenile, and adult stages. Growth, secondary sex characteristics, the liver somatic index, the gonadosomatic index, and fecundity were examined after several lengths of exposure. No significant changes were seen in fry or juvenile growth from 8 to 30 days posthatch (dph). An increase in the ovipositor index (a female secondary sex characteristic) was the most sensitive early response at 60 dph and was seen in fish exposed to EE2 concentrations , 3.5 ng/L. Continuation of the EE2 exposure until 150 dph, through maturation and reproduction, allowed measurement of two sensitive end points: decreased egg fertilization and sex ratio (skewed toward females), both of which were significantly affected at the lowest EE2 concentration tested, 0.32 ng/L. The next most sensitive end point was demasculinization (decreased male secondary sex characteristic index) of males exposed to an EE2 concentration of 0.96 ng/L. The effects of low concentrations of EE2 (0.32 and 0.96 ng/L) were manifested in male fish (decreased male sex characteristics and reduced egg fertilization success), whereas female fish showed no changes in the gonadosomatic index. Exposure to higher EE2 concentrations negatively affected females, as shown by a reduced gonadosomatic index at 150 dph in fish exposed to ,3.5 ng/L EE2. Although there were some end points that showed changes at 60 dph, the reproductive end points and external sex characteristics measured in mature fish at 150 dph were more sensitive, with response thresholds of EE2 ranging from 0.32 to 0.96 ng/L. The concentrations of EE2 that negatively affected fathead minnows were similar to or lower than those detected in many municipal wastewater effluents. In conclusion, life-cycle exposure of fathead minnows proved to be a very sensitive bioassay, and responses were seen at concentrations of less than 1 ng/L, which are environmentally relevant concentrations of EE2. © 2005 Government of Canada. Exclusive worldwide publication rights in the article have been transferred to John Wiley & Sons, Inc. Environ Toxicol 20: 131,141, 2005. [source] Presence of natural and anthropogenic organic contaminants and potential fish health impacts along two river gradients in Alberta, CanadaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2010Ken M. Jeffries Abstract In the current study, 28 organic contaminants were measured, many with estrogen-like activity, in water collected from 16 sites on two rivers in the South Saskatchewan River Basin, Alberta, Canada. The compounds detected included synthetic estrogens (birth control pill compounds and hormone therapy drugs) downstream of municipal wastewater effluents and natural hormones downstream of municipal wastewater effluents and in agricultural areas. Greater concentrations of cholesterol and derivatives, phytosterols, and fecal sterols were measured at the most downstream sites, which indicates cumulative inputs of such compounds in these rivers. A native minnow (longnose dace, Rhinichthys cataractae) was sampled to assess pathophysiological responses to exposure to compounds with estrogen-like activity. Hepatic vitellogenin protein was detected in at least one adult male longnose dace from 14 of 15 sites sampled for fish. Vitellogenin was negatively correlated with hepatosomatic (r,=,,0.47, p,<,0.001) and gonadosomatic (r,=,,0.44, p,<,0.003) indices, which suggests potential health impacts in male longnose dace in the South Saskatchewan River Basin. The current study demonstrates that organic contaminants, many with estrogen-like activity, are distributed over hundreds of kilometers throughout the South Saskatchewan River Basin and not just downstream of major point-sources. Therefore, many activities within these basins impact water quality in the South Saskatchewan River Basin and affect endemic longnose dace populations. Environ. Toxicol. Chem. 2010;29:2379,2387. © 2010 SETAC [source] Die-off of Cryptosporidium parvum in soil and wastewater effluentsJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2007A.M. Nasser Abstract Aims:, To determine the effect of biotic and abiotic components of soil on the viability and infectivity of Cryptosporidium parvum, and evaluate the suitability of viability tests as a surrogate for oocyst infectivity under various environmental settings. Methods and Results:, The die-off of C. parvum in saturated and dry loamy soil was monitored over time by immunofluorescence assay (IFA) and PCR to estimate oocysts viability and by cell culture to estimate oocysts infectivity. Pseudomonas aeruginosa activity resulted in digestion of the outer layer of the oocysts, as demonstrated by loss of the ability to react in IFA. Whereas, P. aeruginosa activity did not affect the DNA amplification by PCR. A 1-log reduction in the oocysts infectivity was observed at 30 °C in distilled water and in saturated soil while oocysts viability was unchanged. Incubation for 10 days in dry loamy soil at 32 °C resulted in a 3-log10 reduction in their infectivity while no change of oocysts viability was recorded. Conclusions:, Under low temperature, C. parvum oocysts may retain their infectivity for a long time. Soil desiccation and high temperatures enhance the die-off rate of C. parvum. Significance and Impact of the Study:, Previous die-off studies of C. parvum used viability tests that do not necessarily reflect the oocyst infectivity. Under low temperatures, there was an agreement observed between viability and infectivity tests and oocysts retained their infectivity for a long time. Desiccation and high temperatures enhance the loss of infectivity of C. parvum. The presented die-off data have significant implications on the management of wastewater reuse in warm environments. [source] Acinetobacter bioreporter assessing heavy metals toxicityJOURNAL OF BASIC MICROBIOLOGY, Issue 5 2006Desouky Abd-El-Haleem Dr. This work was conducted to employ a whole cell-based biosensor to monitor toxicity of heavy metals in water and wastewater. An isolate of industrial wastewater bacterium, Acinetobacter sp. DF4, was genetically modified with lux reporter gene to create a novel bioluminescent bacterial strain, designated as DF4/PUTK2. This bioreporter can investigate the toxicity through light inhibition due to cell death or metabolic burden and the specific stress effects of the tested soluble materials simultaneously. The use of Acinetobacter DF4/PUTK2 as a bioluminescent reporter for heavy metal toxicity testing and for the application of wastewater treatment influent toxicity screening is presented in this study. Among eight heavy metals tested, the bioluminescence of DF4/PUTK2 was most sensitive to Zn, Cd, Fe, Co, Cr followed by Cu in order of decreasing sensitivity. The same pattern of sensitivity was observed when several contaminated water and wastewater effluents were assayed. This work suggested that luxCDABE -marked Acinetobacter bacterium DF4/PUTK2 can be used to bioassay the ecotoxicity of wastewater and effluent samples contaminated with heavy metals. Using this assay, it is possible to pre-select the more toxic samples for further chemical analysis and to discard wastewater samples with low or no inhibition because they are not toxic to the environment. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | ||||||||||