Sonya Kleywegt

Ontario Ministry of the Environment, Toronto, Ontario, Canada

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Publications (26)64.65 Total impact

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    ABSTRACT: Digestion of municipal wastewater biosolids is a necessary prerequisite to their beneficial use in land application, in order to protect public health and the receiving environment. In this study, 13 pharmaceuticals and personal care products (PPCPs), 11 musks, and 17 polybrominated diphenyl ethers were analyzed in 84 samples including primary sludge, waste activated sludge, digested biosolids, dewatered biosolids, and dewatering centrate or filtrate collected from five wastewater treatment plants with aerobic or anaerobic digestion. Aerobic digestion processes were sampled during both warm and cold temperatures to analyze seasonal differences. Among the studied compounds, triclosan, triclocarban, galaxolide, and BDE-209 were the substances most frequently detected under different treatment processes at levels up to 30,000 ng/g dry weight. Comparing aerobic and anaerobic digestion, it was observed that the levels of certain PPCPs and musks were significantly higher in anaerobically digested biosolids, relative to the residues from aerobic digestion. Therefore, aerobic digestion has the potential advantage of reducing levels of PPCPs and musks. On the other hand, anaerobic digestion has the advantage of recovering energy from the biosolids in the form of combustible gases while retaining the nutrient and soil conditioning value of this resource. © 2015 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.
    No preview · Article · Jul 2015 · Journal of Environmental Quality
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    ABSTRACT: Concentrations and percent loadings of pharmaceutically-active compounds (PhACs) and other emerging contaminants (ECs) released from healthcare facilities (2 hospitals and a long-term-care facility) to a sewage treatment plant (STP) in a large urban sewershed was evaluated. An additional hospital outside the sewershed was also monitored. Fourteen of the 24 steroids /hormones and 88 of the 117 PhACs and ECs were detected at least once. Commonly used substances including cotinine, caffeine and its metabolite1,7-dimethylxanthine, ibuprofen and naproxen (analgesics), venlafaxine (antidepressant) and DEET (insect repellant) were detected in all samples at all sites. Concentrations detected in the large specialty hospital outside the sewershed were similar to those within the sewershed. Cytotoxic drugs (tamoxifen and cyclophosphamide) and x-ray contrast media (iopamidol and diatrizoic acid) were infrequently detected in hospital effluents. Analysis for antibiotics indicated that azithromycin, clarithromycin, ciprofloxacin, erythromycin, ofloxacin and sulfamethoxazole were consistently detected in hospital wastewaters as was triclosan (antibacterial agent). Fifteen compounds individually contributed greater than one percent to the total PhAC and EC load to the STP from the 2 hospitals in the sewershed, and nine compounds in the STP effluent exceeded ecotoxicological criteria. This survey demonstrated that point source discharges from healthcare facilities in this sewershed make a small contribution to the overall PhAC and EC loading when compared to the total concentrations entering the receiving STP. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    No preview · Article · Jun 2015 · Environmental Toxicology and Chemistry
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    Ruth N. Hull · Sonya Kleywegt · Julie Schroeder
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    ABSTRACT: A risk-based screening exercise was carried out to evaluate the significance of chemicals of emerging concern measured in water and sediment of the Great Lakes Basin. Chemical classes included pesticides, pharmaceuticals, organic wastewater constituents, nonylphenol ethoxylates, perfluorinated surfactants, chlorinated paraffins, synthetic musks and flame retardants. Maximum measured concentrations were compared to benchmarks selected or developed to reflect a conservative no-effect level and/or the lowest-effect level. These benchmarks reflected traditional effect information such as survival, growth and reproduction. From this analysis, several pesticides, pharmaceuticals, polycyclic aromatic hydrocarbons and nonylphenol ethoxylates were identified as potential concerns and needs for further work were identified. Five of these chemicals (all pesticides) were identified in waters of both the US and Canada (azinphos-methyl, chlorpyrifos, diazinon, malathion and metolachlor). Chlopyrifos, malathion and metolachlor are still registered for use in both jurisdictions; diazinon is registered for use only in the US and azinphos-methyl is not registered for use in either jurisdiction, reflecting the persistence of these chemicals. The results of this screening exercise also were compared to those of several other studies, revealing some common chemicals. Although there are several uncertainties and data gaps in the benchmarks and monitoring data used in the current screening exercise, the results of this risk-based screening can be used by agencies for priority setting, program development, and to support ongoing collaborative research and monitoring programs.
    Full-text · Article · Dec 2014 · Journal of Great Lakes Research
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    ABSTRACT: Contaminants of emerging concern (CEC) have been detected in drinking water world-wide. The source of most of these compounds is generally attributed to contamination from municipal wastewater. Traditional water sampling methods (grab or composite) often require the concentration of large amounts of water in order to detect trace levels of these contaminants. The Polar Organic Compounds Integrative Sampler (POCIS) is a passive sampling technology that has been developed to concentrate trace levels of CEC to provide time-weighted average concentrations for individual compounds in water. However, few studies to date have evaluated whether POCIS is suitable for monitoring contaminants in drinking water. In this study, the POCIS was evaluated as a monitoring tool for CEC in drinking water over a period of 2 and 4 weeks with comparisons to typical grab samples. Seven "indicator compounds" which included carbamazepine, trimethoprim, sulfamethoxazole, ibuprofen, gemfibrozil, estrone and sucralose, were monitored in five drinking water treatment plants (DWTPs) in Ontario. All indicator compounds were detected in raw water samples from the POCIS in comparison to six from grab samples. Similarly, four compounds were detected in grab samples of treated drinking water, whereas six were detected in the POCIS. Sucralose was the only compound that was detected consistently at all five plants. The POCIS technique provided integrative exposures of CECs in drinking water at lower detection limits, while episodic events were captured via traditional sampling methods. There was evidence that the accumulation of target compounds by POCIS is a dynamic process, with adsorption and desorption on the sorbent occurring in response to ambient levels of the target compounds in water. CECs in treated drinking water were present at low ng L(-1) concentrations, which are not considered to be a threat to human health.
    Full-text · Article · Feb 2014 · Environmental Sciences: Processes and Impacts
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    ABSTRACT: This study investigated the changes of conventional parameters, metals, volatile organic compounds (VOCs), acid-base-neutral extractables (ABNs) and selected microcontaminants (MCs) in effluents from three activated sludge (AS) systems including conventional AS (CAS), nitrifying AS (NAS) and biological nutrient removal (BNR) processes at pilot scale under simulated winter (12 o C) and summer (18 o C) wastewater temperatures typical of southern Ontario, Canada. The reductions in the conventional parameters within and between seasons was comparable for COD (77-86%), CBOD 5 (91-96%), TAN (22-43% CAS and 99% for NAS and BNR) and TP (25 to 49% CAS and NAS; and >90% in BNR). For the 18 metals considered, the percent reduction for most metals was better in the NAS and BNR plants for Phase 1 (12 o C) when compared to the CAS pilot plant. In Phase 2 (18 o C) the percent reduction between the CAS, NAS and BNR pilot plants was mostly comparable except for Ba, Pb, Mn, Mo and Ni with a lower reduction in the BNR pilot plant. A suite of 52 volatile organic compounds (VOCs) and 60 acid-base-neutral extractables (ABNs) were monitored in the common primary effluent (PE) and the three effluents. In all cases the monitored VOCs and ABNs were found to be below the detection limits (DL) of 4 and 0.2 μg/L, respectively. A suite of 47 MCs covering various therapeutic classes of pharmaceuticals, surfactants and a plasticizer were analyzed. A substantial number of samples were at or below DL which ranged from 1 to 20 ng/L and the percent detection varied by phase and MC. Significant variability, characteristic of MC concentrations in complex matrices, was evident within and between treatments in each phase. A distributional statistical analysis for left censored data was used along with other semi-quantitative approaches to better understand the treatment performance of the pilot plants with respect to MCs.
    Full-text · Conference Paper · Oct 2013
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    ABSTRACT: Environmental agencies must monitor an ever increasing range of contaminants of emerging concern, including endocrine disrupting compounds (EDCs). An alternative to using ultra-trace chemical analysis of samples for EDCs is to test for biological activity using in vitro screening assays, then use these assay results to direct analytical chemistry approaches. In this study, we used both analytical approaches and in vitro bioassays to characterize the EDCs present in treated wastewater from four wastewater treatment plants (WWTPs) in Ontario, Canada. Estrogen-mediated activity was assessed using a yeast estrogenicity screening (YES) assay. An in vitro competitive binding assay was used to assess capacity to interfere with binding of the thyroid hormone, thyroxine (T4) to the recombinant human thyroid hormone transport protein, transthyretin (i.e. hTTR). An in vitro binding assay with a rat peroxisome proliferator responsive element transfected into a rainbow trout gill cell line was used to evaluate binding and subsequent gene expression via the peroxisome proliferator activated receptor (PPAR). Analyses of a suite of contaminants known to be EDCs in extracts from treated wastewater were conducted using either gas chromatography with mass spectrometry (GC-MS) or liquid chromatography with tandem mass spectrometry (LC-MS/MS). Estrogenic activity was detected in the YES assay only in those extracts that contained detectable amounts of estradiol (E2). There was a positive relationship between the degree of response in the T4-hTTR assay and the amounts of polybrominated diphenyl ether (PBDE) congeners 47 and 99, triclosan and the PBDE metabolite, 4-OH-BDE17. Several wastewater extracts gave a positive response in the PPAR assay, but these responses were not correlated with the amounts of any of the EDCs analyzed by LC-MS/MS. Overall, these data indicate that a step-wise approach is feasible using a combination of in vitro testing and instrumental analysis to monitor for EDCs in wastewater and other environmental matrixes.
    Full-text · Article · Mar 2013 · Science of The Total Environment
  • N Gottschall · E Topp · M Edwards · M Payne · S Kleywegt · P Russell · D.R. Lapen
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    ABSTRACT: A land application of dewatered municipal biosolids (DMB) was conducted on an agricultural field in fall 2008 at a rate of 22Mg dry weight (dw) ha(-1). Pre- and post- application, hormone, sterol and fecal indicator bacteria concentrations were measured in tile drainage water, groundwater (2, 4, 6m depth), surface soil cores, and DMB aggregates incorporated in the soil (∼0.2m depth) for a period of roughly 1year post-application. Hormones and sterols were detected up to 1year post-application in soil and in DMB aggregates. Hormone (androsterone, desogestrel, estrone) contamination was detected briefly in tile water samples (22d and ∼2months post-app), at lowngL(-1) concentrations (2-34ngL(-1)). Hormones were not detected in groundwater. Sterols were detected in tile water throughout the study period post-application, and multiple fecal sterol ratios suggested biosolids as the source. Coprostanol concentrations in tile water peaked at >1000ngL(-1) (22d post-app) and were still >100ngL(-1) at 6months post-application. Fecal indicator bacteria were detected throughout the study period in tile water, groundwater (⩽2m depth), soil and DMB aggregate samples. These bacteria were strongly linearly related to coprostanol in tile water (R(2)>0.92, p<0.05). The limited transport of hormones and sterols to tile drainage networks may be attributed to a combination of the hydrophobicity of these compounds and limited macroporosity of the field soil. This transitory contamination from hormones and sterols is unlikely to result in any significant pulse exposure risk in subsurface drainage and groundwater.
    No preview · Article · Jan 2013 · Chemosphere
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    ABSTRACT: Dewatered municipal biosolids (DMBs) were applied to a field at a rate of ~22 Mg dw ha(-1) in October 2008. Pharmaceuticals and personal care products (PPCPs) were monitored in groundwater, tile drainage, soil, DMB aggregates incorporated into the soil post-land application, and in the grain of wheat grown on the field for a period of ~1 year following application. Over 80 PPCPs were analyzed in the source DMB. PPCPs selected for in-depth monitoring included: antibiotics (tetracyclines, fluoroquinolones), bacteriocides (triclosan, triclocarban), beta-blockers (atenolol, propranolol, metaprolol), antidepressants (fluoxetine, citalopram, venlafaxine, sertraline), antifungals (miconazole), analgesics (acetaminophen, ibuprofen) and anticonvulsants (carbamazepine). PPCPs in tile were observed twice, ~3 weeks and 2 months post-application. Of all PPCPs measured in tile drainage, only carbamazepine, ibuprofen, acetaminophen, triclosan, triclocarban, venlafaxine, and citalopram were detected (5-74 ng L(-1)). PPCPs were not detected in groundwater >2 m depth below the soil surface, and concentrations above detection limits at 2 m depth were only observed once just after the first rain event post-application. In groundwater, all compounds found in tile, except carbamazepine, acetaminophen and citalopram, were detected (10-19 ng L(-1)). PPCPs were detected in DMB aggregates incorporated in soil up to 1 year post-application, with miconazole and fluoxetine having the lowest percent reductions over 1 year (~50%). For several compounds in these aggregates, concentration declines were of exponential decay form. No PPCPs were detected in the grain of wheat planted post-application on the field. No PPCPs were ever detected in water, soil or grain samples from the reference plot, where no DMB was applied.
    Full-text · Article · Apr 2012 · Chemosphere
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    ABSTRACT: The Ontario Ministry of the Environment (MOE) conducted a survey in 2006 on emerging organic contaminants (EOCs) which included pharmaceuticals, hormones and bisphenol A (BPA). The survey collected 258 samples over a 16 month period from selected source waters and 17 drinking water systems (DWSs), and analyzed them for 48 EOCs using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and isotope dilution mass spectrometry (IDMS) for the highest precision and accuracy of analytical data possible. 27 of the 48 target EOCs were detected in source water, finished drinking water, or both. DWSs using river and lake source water accounted for>90% detections. Of the 27 EOCs found, we also reported the first detection of two antibiotics roxithromycin and enrofloxacin in environmental samples. The most frequently detected compounds (≥ 10%) in finished drinking water were carbamazepine (CBZ), gemfibrozil (GFB), ibuprofen (IBU), and BPA; with their concentrations accurately determined by using IDMS and calculated to be 4 to 10 times lower than those measured in the source water. Comparison of plant specific data allowed us to determine removal efficiency (RE) of these four most frequently detected compounds in Ontario DWSs. The RE of CBZ was determined to be from 71 to 93% for DWSs using granulated activated carbon (GAC); and was 75% for DWSs using GAC followed by ultraviolet irradiation (UV). The observed RE of GFB was between 44 and 55% in DWSs using GAC and increased to 82% when GAC was followed by UV. The use of GAC or GAC followed by UV provided an RE improvement of BPA from 80 to 99%. These detected concentration levels are well below the predicted no effect concentration or total allowable concentration reported in the literature. Additional targeted, site specific comparative research is required to fully assess the effectiveness of Ontario DWSs to remove particular compounds of concern.
    No preview · Article · Feb 2011 · Science of The Total Environment
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    ABSTRACT: This study investigated the changes of conventional parameters and selected microcontaminants (MCs) in effluents from three activated sludge (AS) systems including conventional AS (CAS), nitrifying AS (CAS-N) and biological nutrient removal (CAS-BNR) processes at pilot scale. The effluents were also characterized with a suite of biological assays and lifecycle investigations. The biological assays tests included rainbow trout acute lethality (96-h), Daphnia magna acute lethality (48-h), fathead minnow survival and growth (7-d), Ceriodaphnia dubia survival and reproduction (7-d), duckweed growth inhibition (7-d) and algal growth inhibition (72-h). Other tests included receptor binding tests (yeast estrogenic screening (YES), yeast androgenic screening (YAS) and thyroid transport receptor (T4/hTTR)) and whole organism tests (fathead minnow lifecycle exposure test, zebrafish reproduction test). For most chemistry endpoints and long-term fish health endpoints, the CAS-BNR process was the most effective in reducing contaminant concentration levels and toxic effects.
    Full-text · Article · Jan 2011
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    Full-text · Article · Apr 2010 · Science of The Total Environment
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    ABSTRACT: Polybrominated diphenyl ethers (PBDEs), perfluorinated alkylated substances (PFAS), and metals were monitored in tile drainage and groundwater following liquid (LMB) and dewatered municipal biosolid (DMB) applications to silty-clay loam agricultural field plots. LMB was applied (93,500 Lha(-1)) in late fall 2005 via surface spreading on un-tilled soil (SS(LMB)), and a one-pass aerator-based pre-tillage prior to surface spreading (Aerway SSD) (A). The DMB was applied (8 Mg dw ha(-1)) in early summer 2006 on the same plots by injecting DMB beneath the soil surface (DI), and surface spreading on un-tilled soil (SS(DMB)). Key PBDE congeners (BDE-47, -99, -100, -153, -154, -183, -209) comprising 97% of total PBDE in LMB, had maximum tile effluent concentrations ranging from 6 to 320 ng L(-1) during application-induced tile flow. SS(LMB) application-induced tile mass loads for these PBDE congeners were significantly higher than those for control
    No preview · Article · Dec 2009 · Science of The Total Environment
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    Full-text · Article · Nov 2009 · Science of The Total Environment
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    ABSTRACT: Municipal biosolids are a useful source of nutrients for crop production, and commonly used in agriculture. In this field study, we applied dewatered municipal biosolids at a commercial rate using broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 21 and 34 days following the application on 2 m(2) microplots to evaluate surface runoff of various pharmaceuticals and personal care products (PPCPs), namely atenolol, carbamazepine, cotinine, caffeine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole, triclosan and triclocarban. There was little temporal coherence in the detection of PPCPs in runoff, various compounds being detected maximally on days 1, 3, 7 or 36. Maximum concentrations in runoff ranged from below detection limit (gemfibrozil) to 109.7 ng L(-1) (triclosan). Expressing the total mass exported as a percentage of that applied, some analytes revealed little transport potential (<1% exported; triclocarban, triclosan, sulfamethoxazole, ibuprofen, naproxen and gemfibrozil) whereas others were readily exported (>1% exported; acetaminophen, carbamazepine, caffeine, cotinine, atenolol). Those compounds with little transport potential had log K(ow) values of 3.18 or greater, whereas those that were readily mobilized had K(ow) values of 2.45 or less. Maximal concentrations of all analytes were below toxic concentrations using a variety of endpoints available in the literature. In summary, this study has quantified the transport potential in surface runoff of PPCPs from land receiving biosolids, identified that log K(ow) may be a determinant of runoff transport potential of these analytes, and found maximal concentrations of all chemicals tested to be below toxic concentrations using a variety of endpoints.
    Full-text · Article · Aug 2009 · Science of The Total Environment
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    ABSTRACT: Land application of municipal biosolids can be a source of environmental contamination by pharmaceutical and personal care products (PPCPs). This study examined PPCP concentrations/temporally discrete mass loads in agricultural tile drainage systems where two applications of biosolids had previously taken place. The field plots received liquid municipal biosolids (LMB) in the fall of 2005 at an application rate of approximately 93,500 L ha (-1), and a second land application was conducted using dewatered municipal biosolids (DMB) applied at a rate of approximately 8Mg dw ha (-1) in the summer of 2006 [corrected].The DMB land application treatments consisted of direct injection (DI) of the DMB beneath the soil surface at a nominal depth of approximately 0.11 m, and surface spreading (SS) plus subsequent tillage incorporation of DMB in the topsoil (approximately 0.10 m depth). The PPCPs examined included eight pharmaceuticals (acetaminophen, fluoxetine, ibuprofen, gemfibrozil, naproxen, carbamazepine, atenolol, sulfamethoxazole), the nicotine metabolite cotinine, and two antibacterial personal care products triclosan and triclocarban. Residues of naproxen, cotinine, atenolol and triclosan originating from the fall 2005 LMB application were detected in tile water nearly nine months after application (triclocarban was not measured in 2005). There were no significant differences (p>0.05) in PPCP mass loads among the two DMB land application treatments (i.e., SS vs. DI); although, average PPCP mass loads late in the study season (>100 days after application) were consistently higher for the DI treatment relative to the SS treatment. While the concentration of triclosan (approximately 14,000 ng g(-1) dw) in DMB was about twice that of triclocarban (approximately 8000 ng g(-1) dw), the average tile water concentrations for triclosan were much higher (43+/-5 ng L(-1)) than they were for triclocarban (0.73+/-0.14 ng L(-1)). Triclosan concentrations (maximum observed in 2006 approximately 235 ng L(-1)) in tile water resulting from land applications may warrant attention from a toxicological perspective.
    Full-text · Article · Apr 2009 · Science of The Total Environment
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    ABSTRACT: Municipal biosolids are a source of nutrients for crop production. Beneficial Management Practices (BMPs) can be used to minimize the risk of contamination of adjacent water resources with chemical or microbial agents that are of public or environmental health concern. In this field study, we applied biosolids slurry at a commercial rate using either subsurface injection or broadcast application followed by incorporation. Precipitation was simulated at 1, 3, 7, 22, 36 and 266 days post-application on 2 m(2) microplots to evaluate surface runoff of 9 model pharmaceuticals and personal care products (PPCPs), atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, ibuprofen, acetaminophen, sulfamethoxazole and triclosan. In runoff from the injected plots, concentrations of the model PPCPs were generally below the limits of quantitation. In contrast, in the broadcast application treatment, the concentrations of atenolol, carbamazepine, cotinine, gemfibrozil, naproxen, sulfamethoxazole and triclosan on the day following application ranged from 70-1477 ng L(-1) in runoff and generally declined thereafter with first order kinetics. The total mass of PPCPs mobilized in surface runoff per m(2) of the field ranged from 0.63 microg for atenolol to 21.1 microg for ibuprofen. For ibuprofen and acetaminophen, concentrations in runoff first decreased and then increased, suggesting that these drugs were initially chemically or physically sequestered in the biosolids slurry, and subsequently released in the soil. Carbamazepine and triclosan were detected at low concentrations in a runoff event 266 days after broadcast application. Overall, this study showed that injection of biosolids slurry below the soil surface could effectively eliminate surface runoff of PPCPs.
    Full-text · Article · Jul 2008 · Science of The Total Environment
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    ABSTRACT: Polycyclic and nitro musk (PNM) fragrances in personal care products persist and bioaccumulate in the environment following wastewater discharges and land application of biosolids. Influent and effluent concentrations, seasonal variations, and process removal efficiencies of 11 PNMs were investigated at six wastewater treatment plants representing four typical Canadian treatment processes: lagoon, oxidation ditch, extended aeration, and conventional activated sludge. Influent concentrations were as high as 40 000 ng/L for polycyclic musks and 400 ng/L for nitro musks, and showed some seasonal fluctuation. Effluent concentrations were as high as 4000 ng/L and 150 ng/L for polycyclic and nitro musks, respectively. Lagoon treatment produced the highest percent removal (> 95%) and the lowest effluent concentrations of PNMs, with process temperature exerting some influence on removal. Results indicate that simple hydraulic or solids retention time are not strong predictors of PNM removals from wastewater. Effluent PNM concentrations were extrapolated to all treatment plants in the watershed to estimate concentrations along the Grand River and its tributaries.
    No preview · Article · Jun 2008 · Journal of Environmental Engineering and Science
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    ABSTRACT: This study examined bacteria and nutrient quality in tile drainage and shallow ground water resulting from a fall land application of liquid municipal biosolids (LMB), at field application rates of 93,500 L ha(-1), to silt-clay loam agricultural field plots using two different land application approaches. The land application methods were a one-pass AerWay SSD approach (A), and surface spreading plus subsequent incorporation (SS). For both treatments, it took between 3 and 39 min for LMB to reach tile drains after land application. The A treatment significantly (p < 0.1) reduced application-induced LMB contamination of tile drains relative to the SS treatment, as shown by mass loads of total Kjeldahl N (TKN), NH(4)-N, Total P (TP), PO(4)-P, E. coli., and Clostridium perfringens. E. coli contamination resulting from application occurred to at least 2.0-m depth in ground water, but was more notable in ground water immediately beneath tile depth (1.2 m). Treatment ground water concentrations of selected nutrients and bacteria for the study period ( approximately 46 d) at 1.2-m depth were significantly higher in the treatment plots, relative to control plots. The TKN and TP ground water concentrations at 1.2-m depth were significantly (p < 0.1) higher for the SS treatment, relative to the A treatment, but there were no significant (p > 0.1) treatment differences for the bacteria. For the macroporous field conditions observed, pre-tillage by equipment such as the AerWay SSD, will reduce LMB-induced tile and shallow ground water contamination compared to surface spreading over non-tilled soil, followed by incorporation.
    No preview · Article · May 2008 · Journal of Environmental Quality
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    ABSTRACT: Pharmaceuticals and personal care products (PPCPs) enter municipal wastewater after use by consumers, and may be degraded during the wastewater treatment process, remain unchanged in effluent, or partition to solids. Their detection in environmental matrices is a result of wastewater effluent discharges and land application of digested biosolids. Results of environmental effects research to date indicate that some PPCPs exhibit detrimental effects such as endocrine disruption or inhibition of an organism's ability to excrete xenobiotics.In 2002 Environment Canada and the Ontario Ministry of Environment embarked on a large-scale research study to generate information for development of risk management strategies to control the release of PPCPs into the Canadian environment. This study included development of analytical methods; surveys of PPCPs in influents, effluents, and solids; and controlled bench-scale studies. This presentation provides an overview of these recent Canadian research activities.
    No preview · Article · Dec 2007
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    ABSTRACT: Analytical technology is continuously improving, developing better methods for isolating and concentrating trace compounds in environmental samples. Polycyclic and nitro musks (PNMs) are one group of emerging trace compounds detected in municipal wastewater. Differences in sample storage, preparation, and extraction methods for their measurement have led to variability in results. We analyzed 11 PNMs by GC/MS and compared the results of different storage times and extraction methods (supercritical fluid (SFE) or microwave-assisted (MAE)) for 202 samples of primary sludge, waste activated sludge (WAS), raw sludge, and aerobically/anaerobically digested biosolids collected from Canadian municipal wastewater treatment plants. Sixty-three air-dried samples were extracted by SFE, and 139 air-dried, centrifuged, or filtered samples were extracted by MAE. The mean surrogate recoveries were 89% (standard deviation (SD)=11%) for d(10)-anthracene by SFE and 88% (SD=14%) for d(10)-phenanthrene by MAE. Storage study results showed that PNM concentrations changed by a mean of 7% and 9% for primary sludge and WAS respectively after four weeks and decreased up to 25% after 13.5 months of storage in amber glass containers at -18 degrees C. Air-drying of sludge at room temperature caused losses of about 50% of PNM concentrations compared to centrifugation. The proportions of PNMs present in the liquid phase of sludge samples were less than 5% compared to proportions in the sludge solids. The most complete liquid-solid separation was achieved by filtration of frozen/thawed sludge samples, producing a liquid phase that contained less than 1% of the total musk content of the sample.
    No preview · Article · Mar 2007 · Chemosphere