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Edward Topp - One of the best experts on this subject based on the ideXlab platform.

  • dissipation of triclosan triclocarban carbamazepine and naproxen in agricultural soil following surface or sub surface application of dewatered municipal Biosolids
    Science of The Total Environment, 2015
    Co-Authors: Abdul Jabbar Alrajab, Lyne Sabourin, David R Lapen, Edward Topp
    Abstract:

    In many jurisdictions land application of municipal Biosolids is a valued source of nutrients for crop production. The practice must be managed to ensure that crops and adjacent water are not subject to contamination by pharmaceuticals or other organic contaminants. The broad spectrum antimicrobial agents triclosan (TCS) and triclocarban (TCC), the anti-epileptic drug carbamazepine (CBZ), and the nonsteroidal anti-inflammatory drug naproxen (NAP) are widely used and are carried in Biosolids. In the present study, the effect of Biosolids and depth of placement in the soil profile on the rates of TCS, TCC, CBZ, and NAP dissipation were evaluated under semi-field conditions. Aggregates of dewatered municipal Biosolids (DMBs) supplemented with 14C-labeled residues were applied either on the soil surface or in the subsurface of the soil profile, and incubated over several months under ambient outdoor conditions. The dissipation of TCS, TCC and NAP was significantly faster in sub-surface than surface applied biosolid aggregates. In contrast the dissipation rate for CBZ was the same in surface applied and incorporated aggregates. Overall, the present study has determined a significant effect of depth of placement on the dissipation rate of biodegradable molecules.

  • uptake of pharmaceuticals hormones and parabens into vegetables grown in soil fertilized with municipal Biosolids
    Science of The Total Environment, 2012
    Co-Authors: Lyne Sabourin, David R Lapen, Peter Duenk, Shelly Bontegelok, M Payne, Edward Topp
    Abstract:

    article i nfo Several recent greenhouse studies have established the potential for uptake of human pharmaceuticals from soil fertilized with municipal Biosolids into a variety of crops. In the present study, a field experiment was un- dertaken to evaluate the uptake of organic micropollutants from soil fertilized with municipal Biosolids at a regulated application rate into tomatoes, carrots, potatoes and sweet corn produced under normal farming conditions. The vegetables were grown according to farming practices mandated by the province of Ontario Canada, the key feature being a one-year offset between biosolid application and the harvest of crops for human consumption. Biosolids at application, and crop samples following harvest were analyzed for 118 pharmaceuticals and transformation products, 17 hormones or hormone transformation products, and 6 par- abens. Analyte concentrations in the Biosolids were consistent with those detected in other surveys. Eight of the 141 analytes were detected in one or two crop replicates at concentrations ranging from 0.33 to 6.25 ng/g dry weight, but no analytes were consistently detected above the detection limit in all triplicate treated plots. Overall, this study suggests that the potential for micropollutant uptake into crops under normal farming conditions is low.

  • survey of hormone activities in municipal Biosolids and animal manures
    Environmental Toxicology, 2004
    Co-Authors: Angela Lorenzen, John G Hendel, Allan B Kwabiah, George Lazarovitz, Shabtai Bittman, T A Mcallister, Daniel I Masse, Kenneth L Conn, Edward Topp
    Abstract:

    The potential exists for natural or synthetic hormonal chemicals present in agricultural fertilizers to be transferred to adjacent aquatic environments in order to alter endocrine function in exposed wildlife. Recombinant yeast and mammalian cell line (BG1Luc4E2) assays were used to screen crude organic extracts of municipal Biosolids and animal manures for estrogen-, androgen-, and proges- terone receptor gene transcription activities. Of the biosolid extracts, those samples that had undergone aerobic digestion had no or minimal estrogen- and no androgen receptor gene transcription activities. In contrast, those biosolid samples that had undergone anaerobic digestion had much higher estrogen- and, for all but one site, androgen receptor gene transcription activities. Extracts prepared from animal manure samples had variable levels of androgen- and estrogen receptor gene transcription activities, which may be related to the type, sex, age, and reproductive status of the animals. The diet and treatment of animals with hormone implants also appeared to be factors influencing hormone activity in animal manure. Progesterone receptor gene transcription activity was observed for only one chicken litter sample. Overall, results of this study suggest that in vitro bioassays can be used to survey and detect hormone activity in municipal Biosolids and animal manures. Furthermore, results of these assays can be used to develop

Ines Ahumada - One of the best experts on this subject based on the ideXlab platform.

  • determination of the bioavailable fraction of triclosan in biosolid treated soils using a predictive method and wheat plant bioassays
    Journal of Soils and Sediments, 2016
    Co-Authors: Yanina Corrotea, Pablo Richter, Sally Brown, Betsabet Sepulveda, Loreto Ascar, Ines Ahumada
    Abstract:

    Purpose Triclosan (TCS, 5-chloro-2-(2,4-dichlorophenoxy) phenol) an antimicrobial compound used in a range of household products, is an emerging hydrophobic organic contaminant, that may be incorporated into soil through the application of Biosolids. The present study assessed the bioavailable fraction of TCS in a soil-biosolid system using wheat (Triticum aestivum) plant assays and a predictive extraction method using a solution of hydroxypropyl-β-cyclodextrin (HPCD) to determine if it was a reliable surrogate for this bioassay.

  • determination of lindane leachability in soil biosolid systems and its bioavailability in wheat plants
    Chemosphere, 2011
    Co-Authors: Pamela Caicedo, Andrea Schroder, Nadin Ulrich, Uwe Schroter, Albrecht Paschke, Gerrit Schuurmann, Ines Ahumada, Pablo Richter
    Abstract:

    Abstract The leachability of lindane from different biosolid amended soils was determined and compared to its bioavailability. Sand, soil, and a mixture of soil–sand (1:1 w/w) were spiked with lindane, blended with different amounts of Biosolids, and subjected to a leaching process with water that lasted for 1–28 d. This procedure is in accordance with ISO/TS 21268-1: 2007 . After these batch tests, lindane was extracted from the leachates using three different solvent-free microextraction techniques, including solid phase microextraction (SPME), stir-bar sorptive extraction (SBSE), and silicone rod extraction (SRE). The amount of lindane was determined with thermal desorption and gas chromatography coupled to mass spectrometry (GC–MS). The efficiencies of the three microextraction techniques were statistically different, and the efficiency could be related to the amount of polydimethylsiloxane (PDMS) in each extraction device. However, all of the techniques provide data that shows that the leachability of lindane is dependent on the amount of organic matter contained in the matrix. The results of the lindane leachability assay were compared to the bioavailability of lindane, which was determined by measuring the amount of lindane that accumulated in the roots of wheat plants grown in similar soil–biosolid systems. It was confirmed that the amount of organic matter in the matrix is a determining factor for lindane immobilization. The presence of Biosolids decreases the mobility of lindane in all of the systems under study. Similarly, increasing biosolid concentrations in the soil significantly decreased the bioavailability of lindane and, consequently, plant absorption. The good correlation ( R 2  = 0.997) between the leachability of lindane from the matrix and plant absorption of lindane indicates that the proposed biomimetic methodology can predict the bioavailability of lindane in a time period as short as 7 d. The results of this work confirm that amending contaminated soils with Biosolids is beneficial for immobilizing lindane and helps prevent the percolation of lindane through the soil profile and into groundwater.

  • Polychlorinated biphenyl behavior in soils amended with Biosolids
    Chemosphere, 2010
    Co-Authors: Claudio Leiva, Ines Ahumada, Betsabet Sepulveda, Pablo Richter
    Abstract:

    Abstract Assessment of the mobility of polychlorinated biphenyls (PCBs) in soils, amended with Biosolids at a rate of 30 Mg ha −1 , was performed using an incubation process and leaching columns. The incubation process was carried out for 0, 30, and 60 d under field capacity conditions at 25 °C. The mobility of PCBs was assessed using solutions of 0.5 mol L −1 CaCl 2 and 25 mg L −1 linear alkylbenzenes sulfonate (LAS). Ultrasound-assisted pressurized solvent extraction (US-PSE) was utilized for compound separation from the solid matrix. Compounds were determined by gas chromatography coupled to mass spectrometry. The Biosolids, containing a background PCB concentration about 300 μg kg −1 , were spiked with the analytes at 300 mg kg −1 to obtain a clearer determination of their behavior when the biosolid was mixed with soil. In biosolid-amended soils, an increase was observed in the extractability of PCBs with increasing incubation time, which may be attributed to organic matter breakdown. The leaching column study showed that CaCl 2 was unable to mobilize the PCBs from the biosolid to the soil, whereas LAS mobilized these compounds within the time scale implicit in the experiment (30 d). The most mobilized congeners in the columns corresponded to those with the greatest molecular weight (hexa- and heptachlorinated), probably due to the higher hydrophobicity of these compounds. Results indicate that the presence of important concentrations of LAS in Biosolids could mobilize PCBs from soil to the freatic level.

Ian L Pepper - One of the best experts on this subject based on the ideXlab platform.

  • Comparative Assessment of BGM and PLC/PRF/5 Cell Lines for Enteric Virus Detection in Biosolids
    Food and Environmental Virology, 2019
    Co-Authors: Sherif Abd-elmaksoud, N. Castro-del Campo, Charles P Gerba, Ian L Pepper, Kelly R. Bright
    Abstract:

    The buffalo green monkey (BGM) cell line is required for the detection of enteric viruses in Biosolids through a total culturable viral assay (TCVA) by the United States Environmental Protection Agency. In the present study, BGM and PLC/PRF/5 cell lines were evaluated for TCVA and for their use in determining the incidence of adenoviruses and enteroviruses in raw sludge and Class B Biosolids. Six raw sludge and 17 Class B biosolid samples were collected from 13 wastewater treatment plants from seven U.S. states. Samples were processed via organic flocculation and concentrate volumes equivalent to 4 g total solids were assayed on BGM and PLC/PRF/5 cells. Cell monolayers were observed for cytopathic effect (CPE) after two 14-days passages. Cell lysates were tested for the presence of adenoviruses and enteroviruses by PCR or RT-PCR. The PLC/PRF/5 cells detected more culturable viruses than the BGM cells by CPE (73.9% vs. 56.5%, respectively). 52% of the samples were positive for CPE using both cell lines. No viruses were detected in either cell line by PCR in flasks in which CPE was not observed. No adenoviruses were detected in 13 CPE-positive samples from BGM lysates. In contrast, of the 17 samples exhibiting CPE on PLC/PRF/5 cells, 14 were positive for adenoviruses (82.4%). In conclusion, PLC/PRF/5 cells were superior for the detection of adenoviruses in both raw sludge and Class B Biosolids. Thus, the use of BGM cells alone for TCVA may underestimate the viral concentration in sludge/biosolid samples.

  • long term effects of land application of class b Biosolids on the soil microbial populations pathogens and activity
    Journal of Environmental Quality, 2010
    Co-Authors: Huruy Zerzghi, John P Brooks, Charles P Gerba, Ian L Pepper
    Abstract:

    This study evaluated the influence of 20 annual land applications of Class B Biosolids on the soil microbial community. The potential benefits and hazards of land application were evaluated by analysis of surface soil samples collected following the 20th land application of Biosolids. The study was initiated in 1986 at the University of Arizona Marana Agricultural Center, 21 miles north of Tucson, AZ. The final application of Biosolids was in March 2005, followed by growth of cotton (Gossypium hirsutum L.) from April through November 2005. Surface soil samples (0—30 cm) were collected monthly from March 2005, 2 wk after the final Biosolids application, through December 2005, and analyzed for soil microbial numbers. December samples were analyzed for additional soil microbial properties. Data show that land application of Class B Biosolids had no significant long-term effect on indigenous soil microbial numbers including bacteria, actinomycetes, and fungi compared to unamended control plots. Importantly, no bacterial or viral pathogens were detected in soil samples collected from biosolid amended plots in December (10 mo after the last land application) demonstrating that pathogens introduced via Class B Biosolids only survived in soil transiently. However, plots that received Biosolids had significantly higher microbial activity or potential for microbial transformations, including nitrification, sulfur oxidation, and dehydrogenase activity, than control plots and plots receiving inorganic fertilizers. Overall, the 20 annual land applications showed no long-term adverse effects, and therefore, this study documents that land application of Biosolids at this particular site was sustainable throughout the 20-yr period, with respect to soil microbial properties.

  • Potential Regrowth and Recolonization of Salmonellae and Indicators in Biosolids and Biosolid-Amended Soil
    Applied and Environmental Microbiology, 2005
    Co-Authors: Kathleen J. Zaleski, Charles P Gerba, K. L. Josephson, Ian L Pepper
    Abstract:

    This study evaluated the potential for conversion of Class B to Class A Biosolids with respect to salmonellae and fecal coliforms during solar drying in concrete lined drying beds. Anaerobically (8% solids) and aerobically (2% solids) digested Class B Biosolids were pumped into field-scale drying beds, and microbial populations and environmental conditions were monitored. Numbers of fecal coliforms and salmonellae decreased as temperature and rate of desiccation increased. After 3 to 4 weeks, Class A requirements were achieved in both Biosolids for the pathogens and the indicators. However, following rainfall events, significant increase in numbers was observed for both fecal coliforms and salmonellae. In laboratory studies, regrowth of fecal coliforms was observed in both Biosolids and biosolid-amended soil, but the regrowth of salmonellae observed in the concrete-lined drying beds did not occur. These laboratory studies demonstrated that pathogens decreased in numbers when soil was amended with Biosolids. Based on serotyping, the increased numbers of salmonellae seen in the concrete lined drying beds following rainfall events was most likely due to recolonization due to contamination from fecal matter introduced by animals and not from regrowth of salmonellae indigenous to Biosolids. Overall, we conclude that the use of concrete-lined beds created a situation in which moisture added as rainfall accumulated in the beds, promoting the growth of fecal coliforms and salmonellae added from external sources.

  • Evidence for the absence of Staphylococcus aureus in land applied Biosolids
    Environmental Science & Technology, 2003
    Co-Authors: Patricia A. Rusin, Sheri L. Maxwell, John P Brooks, Charles P Gerba, Ian L Pepper
    Abstract:

    Staphylococcus aureus is an important human pathogen both within the hospital setting and as a community-acquired infection. Recently there has been concern that land applied Biosolids may transmit S. aureus. However, no scientific data are available to document whether Biosolids are a source of S. aureus. To determine if S. aureus is present in Biosolids, we collected samples from 15 sites across the United States. Samples analyzed were as follows: 3 raw untreated sewage samples and 2 undigested primary sewage sludge samples; 23 different biosolid samples; and 27 aerosols obtained during biosolid land application (biosolid aerosols). Although S. aureus were detected in raw sewage samples, none were found in any of the treated Biosolids nor in any biosolid aerosol samples. These results suggest that Biosolids are not a likely source of S. aureus human exposure or infection.

  • bioaerosol transport modeling and risk assessment in relation to biosolid placement
    Journal of Environmental Quality, 2000
    Co-Authors: Scot E Dowd, Charles P Gerba, Ian L Pepper, Suresh D Pillai
    Abstract:

    A field study was performed in which bioaerosols were sampled at a field site undergoing land placement of anaerobically digested, de-watered biosolid material. The data from these field studies were then used to generate microbial release rates from the Biosolids for use in modeling bioaerosol transport. Continuous-point sources represented by large biosolid piles (temporary storage before placement) in the field, and continuous-area sources represented by large fields upon which Biosolids were placed by spraying, were modeled using microbial transport models; and downwind microbial concentrations were generated. These quantified transport data were then entered into microbial dose-response models in an attempt to characterize the risk of pathogenic bacteria and viruses infecting workers and nearby population centers. The risk of viral and bacterial infection to workers at biosolid land application sites is 3:100 and 2:100, respectively, under 2-m/s wind conditions and 1 hr of exposure. The route of exposure proposed in this modelis the transport, inhalation, deposition, and swallowing of bacterial or viral pathogens. Note that these risk models by nature would tend to overestimate the actual risk to populations (wastewater workers) consisting primarily of immunocompetent individuals. Under these low-wind conditions, nearby population centers where such immunocompetent populations may exist (here considered to be 10000 m from the land application sites) are predicted to be at little risk (1.95 x 10 -2 :100) of infection from aerosolized bacteria and at no risk from aerosolized viruses.

Pablo Richter - One of the best experts on this subject based on the ideXlab platform.

  • determination of the bioavailable fraction of triclosan in biosolid treated soils using a predictive method and wheat plant bioassays
    Journal of Soils and Sediments, 2016
    Co-Authors: Yanina Corrotea, Pablo Richter, Sally Brown, Betsabet Sepulveda, Loreto Ascar, Ines Ahumada
    Abstract:

    Purpose Triclosan (TCS, 5-chloro-2-(2,4-dichlorophenoxy) phenol) an antimicrobial compound used in a range of household products, is an emerging hydrophobic organic contaminant, that may be incorporated into soil through the application of Biosolids. The present study assessed the bioavailable fraction of TCS in a soil-biosolid system using wheat (Triticum aestivum) plant assays and a predictive extraction method using a solution of hydroxypropyl-β-cyclodextrin (HPCD) to determine if it was a reliable surrogate for this bioassay.

  • determination of lindane leachability in soil biosolid systems and its bioavailability in wheat plants
    Chemosphere, 2011
    Co-Authors: Pamela Caicedo, Andrea Schroder, Nadin Ulrich, Uwe Schroter, Albrecht Paschke, Gerrit Schuurmann, Ines Ahumada, Pablo Richter
    Abstract:

    Abstract The leachability of lindane from different biosolid amended soils was determined and compared to its bioavailability. Sand, soil, and a mixture of soil–sand (1:1 w/w) were spiked with lindane, blended with different amounts of Biosolids, and subjected to a leaching process with water that lasted for 1–28 d. This procedure is in accordance with ISO/TS 21268-1: 2007 . After these batch tests, lindane was extracted from the leachates using three different solvent-free microextraction techniques, including solid phase microextraction (SPME), stir-bar sorptive extraction (SBSE), and silicone rod extraction (SRE). The amount of lindane was determined with thermal desorption and gas chromatography coupled to mass spectrometry (GC–MS). The efficiencies of the three microextraction techniques were statistically different, and the efficiency could be related to the amount of polydimethylsiloxane (PDMS) in each extraction device. However, all of the techniques provide data that shows that the leachability of lindane is dependent on the amount of organic matter contained in the matrix. The results of the lindane leachability assay were compared to the bioavailability of lindane, which was determined by measuring the amount of lindane that accumulated in the roots of wheat plants grown in similar soil–biosolid systems. It was confirmed that the amount of organic matter in the matrix is a determining factor for lindane immobilization. The presence of Biosolids decreases the mobility of lindane in all of the systems under study. Similarly, increasing biosolid concentrations in the soil significantly decreased the bioavailability of lindane and, consequently, plant absorption. The good correlation ( R 2  = 0.997) between the leachability of lindane from the matrix and plant absorption of lindane indicates that the proposed biomimetic methodology can predict the bioavailability of lindane in a time period as short as 7 d. The results of this work confirm that amending contaminated soils with Biosolids is beneficial for immobilizing lindane and helps prevent the percolation of lindane through the soil profile and into groundwater.

  • Polychlorinated biphenyl behavior in soils amended with Biosolids
    Chemosphere, 2010
    Co-Authors: Claudio Leiva, Ines Ahumada, Betsabet Sepulveda, Pablo Richter
    Abstract:

    Abstract Assessment of the mobility of polychlorinated biphenyls (PCBs) in soils, amended with Biosolids at a rate of 30 Mg ha −1 , was performed using an incubation process and leaching columns. The incubation process was carried out for 0, 30, and 60 d under field capacity conditions at 25 °C. The mobility of PCBs was assessed using solutions of 0.5 mol L −1 CaCl 2 and 25 mg L −1 linear alkylbenzenes sulfonate (LAS). Ultrasound-assisted pressurized solvent extraction (US-PSE) was utilized for compound separation from the solid matrix. Compounds were determined by gas chromatography coupled to mass spectrometry. The Biosolids, containing a background PCB concentration about 300 μg kg −1 , were spiked with the analytes at 300 mg kg −1 to obtain a clearer determination of their behavior when the biosolid was mixed with soil. In biosolid-amended soils, an increase was observed in the extractability of PCBs with increasing incubation time, which may be attributed to organic matter breakdown. The leaching column study showed that CaCl 2 was unable to mobilize the PCBs from the biosolid to the soil, whereas LAS mobilized these compounds within the time scale implicit in the experiment (30 d). The most mobilized congeners in the columns corresponded to those with the greatest molecular weight (hexa- and heptachlorinated), probably due to the higher hydrophobicity of these compounds. Results indicate that the presence of important concentrations of LAS in Biosolids could mobilize PCBs from soil to the freatic level.

Qingfu Ye - One of the best experts on this subject based on the ideXlab platform.

  • meta analysis of biosolid effects on persistence of triclosan and triclocarban in soil
    Environmental Pollution, 2016
    Co-Authors: Qiuguo Fu, Edmond Sanganyado, Qingfu Ye
    Abstract:

    Biosolids are extensively used in agriculture as fertilizers while offering a practical solution for waste disposal. Many pharmaceutical and personal care products (PPCPs), such as triclosan and triclocarban, are enriched in Biosolids. Biosolid amendment changes soil physicochemical properties, which may in turn alter the persistence of PPCPs and hence the risk for secondary contamination such as plant uptake. To delineate the effect of Biosolids on PPCPs persistence, triclosan and triclocarban were used as model compounds in this study and their sorption (Kd) and persistence (t1/2) were determined in different soils before and after biosolid amendment. Biosolids consistently increased sorption of triclosan and triclocarban in soil. The Kd of triclosan increased by 3.9-21 times following amendment of a sandy loam soil with Biosolids at 2-10%. The persistence of both compounds was prolonged, with t1/2 of triclosan increasing from 10 d in the unamended soil to 63 d after biosolid amendment at 10%. The relationship between t1/2 and Kd was further examined through a meta-analysis using data from this study and all relevant published studies. A significant linear relationship between t1/2 and Kd was observed for triclosan (r(2) = 0.69, p < 0.01) and triclocarban (r(2) = 0.38, p < 0.05) in biosolid-amended soils. On the average, when biosolid amendment increased by 1%, t1/2 of triclosan was prolonged by 7.5 d, while t1/2 of triclocarban was extended by 4.7 d. Therefore, biosolid amendment greatly enhances persistence of triclosan and triclocarban, likely due to enhanced sorption or decreased chemical bioavailability. This finding highlights the importance to consider the effect of Biosolids when evaluating the environmental risks of these and other biosolid-borne PPCPs.

  • Meta-analysis of biosolid effects on persistence of triclosan and triclocarban in soil.
    Environmental Pollution, 2015
    Co-Authors: Qiuguo Fu, Edmond Sanganyado, Qingfu Ye
    Abstract:

    Biosolids are extensively used in agriculture as fertilizers while offering a practical solution for waste disposal. Many pharmaceutical and personal care products (PPCPs), such as triclosan and triclocarban, are enriched in Biosolids. Biosolid amendment changes soil physicochemical properties, which may in turn alter the persistence of PPCPs and hence the risk for secondary contamination such as plant uptake. To delineate the effect of Biosolids on PPCPs persistence, triclosan and triclocarban were used as model compounds in this study and their sorption (Kd) and persistence (t1/2) were determined in different soils before and after biosolid amendment. Biosolids consistently increased sorption of triclosan and triclocarban in soil. The Kd of triclosan increased by 3.9–21 times following amendment of a sandy loam soil with Biosolids at 2–10%. The persistence of both compounds was prolonged, with t1/2 of triclosan increasing from 10 d in the unamended soil to 63 d after biosolid amendment at 10%. The relationship between t1/2 and Kd was further examined through a meta-analysis using data from this study and all relevant published studies. A significant linear relationship between t1/2 and Kd was observed for triclosan (r2 = 0.69, p