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Francis Andreux - One of the best experts on this subject based on the ideXlab platform.
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Interactions of Diuron with dissolved organic matter from organic amendments.
The Science of the total environment, 2009Co-Authors: Mathieu Thevenot, Sylvie Dousset, Norbert Hertkorn, Philippe Schmitt-kopplin, Francis AndreuxAbstract:Diuron is frequently detected in some drinking water reservoirs under the Burgundy vineyards, where organic amendments are applied. The environmental effect of these amendments on pesticide transport is ambiguous: on the one hand it could enhance their retention by increasing soil organic carbon content; on the other hand, dissolved organic matter (DOM) could facilitate their transport. Elutions were performed using columns packed with glass beads in order to investigate DOM–Diuron interactions, and the possible co-transport of Diuron and DOM. Four organic amendments (A, B, C and D) were tested; C and D were sampled at fresh (F) and mature (M) stages. An increase in Diuron leaching was observed only for A and DF amendments (up to 16% compared to the DOM-free blank samples), suggesting a DOM effect on Diuron transport. These results could be explained by the higher DOM leaching for A and DF compared to B, CF, CM and DM increasing Diuron–DOM interactions. These interactions seem to be related to the aromatic and aliphatic content of the DOM, determining formation of hydrogen and non-covalent bonds. The degree of organic matter maturity does not seem to have any effect with amendment C, while a reduction in Diuron leaching is observed between DF and DM. After equilibrium dialysis measurement of Diuron–DOM complexes, it appeared that less than 3% of the Diuron applied corresponded to complexes with a molecular weight > 1000 Da. Complexes < 1000 Da could also take part in this facilitated transport.
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Influence of organic amendments on Diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters.
Environmental Pollution, 2008Co-Authors: Mathieu Thevenot, Sylvie Dousset, S. Rousseaux, Francis AndreuxAbstract:The influence of different organic amendments on Diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (Diuron þ metabolites) in the leachates of the VR soil (0.19e0.71%) was lower than in the Bj soil (4.27e8.23%), which could be explained by stronger Diuron adsorption on VR. An increase in the amount of Diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between Diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between Diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence Diuron leaching.
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Leaching of oryzalin and Diuron through undisturbed vineyard soil columns under outdoor conditions.
Chemosphere, 2006Co-Authors: David Landry, Sylvie Dousset, Francis AndreuxAbstract:Field studies monitoring herbicide pollution in the vineyards of Burgundy (France) have revealed that drinking water reservoirs are contaminated with several pre-emergence herbicides. An assessment of the leaching of two such herbicides, Diuron and oryzalin, was therefore performed using lysimeters, under outdoor conditions, from May 2001 to May 2002. Four vineyard soils from Vosne-Roman?(Burgundy) were chosen along a topolithosequence: a rendosol and three calcosols. After 673 mm of rainfall, greater amounts of Diuron than oryzalin were measured in percolates: respectively 0.10-0.84% and 0.02-0.43% of applied herbicide, depending on soils. Measurements for Diuron metabolites detected greater amounts of DCPMU than DCPU in the percolates: respectively 0.05-0.13% and 0-0.04% of the applied Diuron. At the end of the monitoring period, more residues of Diuron than oryzalin were recovered in the soil profiles: respectively 4.6-9% and 1.4-4.4%. The oryzalin residues were found mainly in the upper 10 cm of soil columns, whereas Diuron residues were present in the whole core. The mobility of both oryzalin and Diuron seems fairly well-related to soil organic carbon content; the mobility of Diuron is also related to soil texture (sand and coarse material contents). Under such experimental conditions, this study confirms that Diuron leaching, and therefore potential groundwater contamination, is greater than that of oryzalin.
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leaching of oryzalin and Diuron through undisturbed vineyard soil columns under outdoor conditions
Chemosphere, 2006Co-Authors: David Landry, Sylvie Dousset, Francis AndreuxAbstract:Field studies monitoring herbicide pollution in the vineyards of Burgundy (France) have revealed that drinking water reservoirs are contaminated with several pre-emergence herbicides. An assessment of the leaching of two such herbicides, Diuron and oryzalin, was therefore performed using lysimeters, under outdoor conditions, from May 2001 to May 2002. Four vineyard soils from Vosne-Romanee (Burgundy) were chosen along a topolithosequence: a rendosol and three calcosols. After 673 mm of rainfall, greater amounts of Diuron than oryzalin were measured in percolates: respectively 0.10-0.84% and 0.02-0.43% of applied herbicide, depending on soils. Measurements for Diuron metabolites detected greater amounts of DCPMU than DCPU in the percolates: respectively 0.05-0.13% and 0-0.04% of the applied Diuron. At the end of the monitoring period, more residues of Diuron than oryzalin were recovered in the soil profiles: respectively 4.6-9% and 1.4-4.4%. The oryzalin residues were found mainly in the upper 10 cm of soil columns, whereas Diuron residues were present in the whole core. The mobility of both oryzalin and Diuron seems fairly well-related to soil organic carbon content; the mobility of Diuron is also related to soil texture (sand and coarse material contents). Under such experimental conditions, this study confirms that Diuron leaching, and therefore potential groundwater contamination, is greater than that of oryzalin.
Sylvie Dousset - One of the best experts on this subject based on the ideXlab platform.
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Interactions of Diuron with dissolved organic matter from organic amendments.
The Science of the total environment, 2009Co-Authors: Mathieu Thevenot, Sylvie Dousset, Norbert Hertkorn, Philippe Schmitt-kopplin, Francis AndreuxAbstract:Diuron is frequently detected in some drinking water reservoirs under the Burgundy vineyards, where organic amendments are applied. The environmental effect of these amendments on pesticide transport is ambiguous: on the one hand it could enhance their retention by increasing soil organic carbon content; on the other hand, dissolved organic matter (DOM) could facilitate their transport. Elutions were performed using columns packed with glass beads in order to investigate DOM–Diuron interactions, and the possible co-transport of Diuron and DOM. Four organic amendments (A, B, C and D) were tested; C and D were sampled at fresh (F) and mature (M) stages. An increase in Diuron leaching was observed only for A and DF amendments (up to 16% compared to the DOM-free blank samples), suggesting a DOM effect on Diuron transport. These results could be explained by the higher DOM leaching for A and DF compared to B, CF, CM and DM increasing Diuron–DOM interactions. These interactions seem to be related to the aromatic and aliphatic content of the DOM, determining formation of hydrogen and non-covalent bonds. The degree of organic matter maturity does not seem to have any effect with amendment C, while a reduction in Diuron leaching is observed between DF and DM. After equilibrium dialysis measurement of Diuron–DOM complexes, it appeared that less than 3% of the Diuron applied corresponded to complexes with a molecular weight > 1000 Da. Complexes < 1000 Da could also take part in this facilitated transport.
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Influence of organic amendments on Diuron leaching through an acidic and a calcareous vineyard soil using undisturbed lysimeters.
Environmental Pollution, 2008Co-Authors: Mathieu Thevenot, Sylvie Dousset, S. Rousseaux, Francis AndreuxAbstract:The influence of different organic amendments on Diuron leaching was studied through undisturbed vineyard soil columns. Two composts (A and D), the second at two stages of maturity, and two soils (VR and Bj) were sampled. After 1 year, the amount of residues (Diuron þ metabolites) in the leachates of the VR soil (0.19e0.71%) was lower than in the Bj soil (4.27e8.23%), which could be explained by stronger Diuron adsorption on VR. An increase in the amount of Diuron leached through the amended soil columns, compared to the blank, was observed for the Bj soil only. This result may be explained by the formation of mobile complexes between Diuron and water-extractable organic matter (WEOM) through the Bj soil, or by competition between Diuron and WEOM for the adsorption sites in the soil. For both soils, the nature of the composts and their degree of maturity did not significantly influence Diuron leaching.
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Leaching of oryzalin and Diuron through undisturbed vineyard soil columns under outdoor conditions.
Chemosphere, 2006Co-Authors: David Landry, Sylvie Dousset, Francis AndreuxAbstract:Field studies monitoring herbicide pollution in the vineyards of Burgundy (France) have revealed that drinking water reservoirs are contaminated with several pre-emergence herbicides. An assessment of the leaching of two such herbicides, Diuron and oryzalin, was therefore performed using lysimeters, under outdoor conditions, from May 2001 to May 2002. Four vineyard soils from Vosne-Roman?(Burgundy) were chosen along a topolithosequence: a rendosol and three calcosols. After 673 mm of rainfall, greater amounts of Diuron than oryzalin were measured in percolates: respectively 0.10-0.84% and 0.02-0.43% of applied herbicide, depending on soils. Measurements for Diuron metabolites detected greater amounts of DCPMU than DCPU in the percolates: respectively 0.05-0.13% and 0-0.04% of the applied Diuron. At the end of the monitoring period, more residues of Diuron than oryzalin were recovered in the soil profiles: respectively 4.6-9% and 1.4-4.4%. The oryzalin residues were found mainly in the upper 10 cm of soil columns, whereas Diuron residues were present in the whole core. The mobility of both oryzalin and Diuron seems fairly well-related to soil organic carbon content; the mobility of Diuron is also related to soil texture (sand and coarse material contents). Under such experimental conditions, this study confirms that Diuron leaching, and therefore potential groundwater contamination, is greater than that of oryzalin.
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leaching of oryzalin and Diuron through undisturbed vineyard soil columns under outdoor conditions
Chemosphere, 2006Co-Authors: David Landry, Sylvie Dousset, Francis AndreuxAbstract:Field studies monitoring herbicide pollution in the vineyards of Burgundy (France) have revealed that drinking water reservoirs are contaminated with several pre-emergence herbicides. An assessment of the leaching of two such herbicides, Diuron and oryzalin, was therefore performed using lysimeters, under outdoor conditions, from May 2001 to May 2002. Four vineyard soils from Vosne-Romanee (Burgundy) were chosen along a topolithosequence: a rendosol and three calcosols. After 673 mm of rainfall, greater amounts of Diuron than oryzalin were measured in percolates: respectively 0.10-0.84% and 0.02-0.43% of applied herbicide, depending on soils. Measurements for Diuron metabolites detected greater amounts of DCPMU than DCPU in the percolates: respectively 0.05-0.13% and 0-0.04% of the applied Diuron. At the end of the monitoring period, more residues of Diuron than oryzalin were recovered in the soil profiles: respectively 4.6-9% and 1.4-4.4%. The oryzalin residues were found mainly in the upper 10 cm of soil columns, whereas Diuron residues were present in the whole core. The mobility of both oryzalin and Diuron seems fairly well-related to soil organic carbon content; the mobility of Diuron is also related to soil texture (sand and coarse material contents). Under such experimental conditions, this study confirms that Diuron leaching, and therefore potential groundwater contamination, is greater than that of oryzalin.
Joao Lauro Viana De Camargo - One of the best experts on this subject based on the ideXlab platform.
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transcriptional profile of Diuron induced toxicity on the urinary bladder of male wistar rats to inform mode of action
Toxicological Sciences, 2011Co-Authors: Shadia Muhammad Ihlaseh, Ana Paula Ferragut Cardoso, Maria Luiza Cotrim Sartor De Oliveira, Kathryn A Bailey, Susan D Hester, Carlton P Jones, Hongzu Ren, Douglas C Wolf, Joao Lauro Viana De CamargoAbstract:Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a substituted urea herbicide that induces rat urinary bladder urothelial tumors at high dietary levels (2500 ppm). The specific mode of action and molecular alterations triggered by Diuron, however, have not been clarified. The present study evaluated the dose-dependent effects of mucosal alterations and transcriptional changes in the urinary bladder of rats exposed to Diuron. Six-week-old male Wistar rats were treated with 0, 60, 125, 1250, and 2500 ppm of Diuron in the diet for 20 weeks. Histologic examination showed urothelial hyperplasia present in rats treated with either 1250 or 2500 ppm of Diuron but not 60 or 125 ppm. Comprehensive gene expression analyses of urothelial cell RNA were conducted using Affymetrix microarrays. The numbers of differentially expressed transcripts between each treatment group and control increased with Diuron dose. Based on similar histology and gene expression responses, the treatment groups were regrouped into a high-dose (1250 and 2500 ppm) and low-dose group (60 and 125 ppm). These data suggest that persistent exposure to high dietary concentrations of Diuron induces oxidative stress, increases cellular metabolism, and enhances cell death that is associated with sustained urothelial hyperplasia.
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cytotoxicity and regenerative proliferation as the mode of action for Diuron induced urothelial carcinogenesis in the rat
Toxicological Sciences, 2010Co-Authors: Mitscheli Sanches Da Rocha, Merielen Garcia Nascimento, Ana Paula Ferragut Cardoso, Patricia Lepage Alves De Lima, Edneia Aparecida Zelandi, Joao Lauro Viana De Camargo, Maria Luiza Cotrim Sartor De OliveiraAbstract:Diuron, a substituted urea herbicide, is carcinogenic to the urinary bladder of rats at high dietary levels. Its proposed carcinogenic mode of action (MOA) includes urothelial cytotoxicity and necrosis followed by regenerative cell proliferation and sustained urothelial hyperplasia. Cytotoxicity could be induced either by urinary solids or by chemical toxicity by Diuron and/or metabolites excreted in the urine. Diuron was not genotoxic in a previous single-cell gel (comet) assay, but possible cross-linking activity remained to be evaluated. The present study explored the MOA of Diuron and the effect of urinary acidification on the development of urothelial lesions. Male Wistar rats were fed Diuron (2500 ppm, about 130 mg/kg of body weight) either with or without NH 4 Cl 10,000 ppm to acidify the urine. Reversibility of urothelial changes was also examined. The animals were euthanized after 15, 25, or 30 weeks. Diuron-fed rats had urinary amorphous precipitate and magnesium ammonium phosphate crystals similar to control animals. Groups treated with Diuron + NH 4 Cl showed decreased urinary pH and reduced amounts of urinary crystals and precipitate. Urothelial necrosis and simple hyperplasia were observed by light microscopy and scanning electron microscopy both in Diuron- and in Diuron + NH 4 Cl-treated groups. Cytotoxicity and proliferative changes were mostly reversible. A modified comet assay developed in vitro with Chinese hamster ovary cells showed that Diuron did not induce DNA cross-links. These data suggest that cytotoxicity with consequent regenerative cell proliferation is the predominant MOA for Diuron rat urothelial carcinogenesis, the cytotoxicity being chemically induced and not due to urinary solids.
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effects of Diuron 3 3 4 dichlorophenyl 1 1 dimethylurea on the urinary bladder of male wistar rats
Toxicology, 2006Co-Authors: Merielen Garcia Nascimento, Maria Luiza Cotrim Sartor De Oliveira, Adriano Silva Lima, Joao Lauro Viana De CamargoAbstract:Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a substituted urea herbicide widely used on agricultural crops such as soy, cotton and sugar cane. In a previous long-term study this herbicide exerted carcinogenic activity on the urinary bladder mucosa of male Wistar rats. In general, the genotoxic and mutagenic potentials of Diuron are considered to be negative. The present study aimed to evaluate the mode of action of Diuron on the urinary bladder mucosa of male Wistar rats. Six-week old male Wistar rats were fed pelleted Nuvilab diet mixed with Diuron at 125, 500 and 2500 ppm. As a positive control, 8.3% sodium saccharin (NaS) was fed in the diet. Preceding the sacrifice of the animals at the 20th week, urinary pH was measured and the genotoxic potential of Diuron was evaluated by the comet assay. Histological urothelial lesions in the urinary bladder and in the renal pelvis mucosa, cell proliferation/apoptosis evaluations, and scanning electron microscopy (SEM) of the urinary bladder mucosa were also performed. No DNA changes were found in urothelial or peripheral blood cells, and urinary pH was comparable to controls in all Diuron groups. In the urinary bladder urothelium, the incidence of simple hyperplasia (SH) by light microscopy was significantly increased (7/10; p < 0.005) in the 2500 ppm Diuron group but not at the lower doses. By SEM, three of five animals treated with 2500 ppm Diuron showed urothelial cell necrosis and hyperplasia. In the renal pelvis, the incidence of SH was significantly increased in the Diuron 500 and 2500 ppm and in the NaS 8.3% groups. Cell proliferation was significantly increased in the Diuron 2500 ppm (p < 0.05) and NaS 8.3% (p < 0.05) groups. The results indicate that a high dietary concentration of Diuron is associated with urothelial necrosis and continuous regenerative cell proliferation that leads to urothelial hyperplasia.
David Landry - One of the best experts on this subject based on the ideXlab platform.
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Leaching of oryzalin and Diuron through undisturbed vineyard soil columns under outdoor conditions.
Chemosphere, 2006Co-Authors: David Landry, Sylvie Dousset, Francis AndreuxAbstract:Field studies monitoring herbicide pollution in the vineyards of Burgundy (France) have revealed that drinking water reservoirs are contaminated with several pre-emergence herbicides. An assessment of the leaching of two such herbicides, Diuron and oryzalin, was therefore performed using lysimeters, under outdoor conditions, from May 2001 to May 2002. Four vineyard soils from Vosne-Roman?(Burgundy) were chosen along a topolithosequence: a rendosol and three calcosols. After 673 mm of rainfall, greater amounts of Diuron than oryzalin were measured in percolates: respectively 0.10-0.84% and 0.02-0.43% of applied herbicide, depending on soils. Measurements for Diuron metabolites detected greater amounts of DCPMU than DCPU in the percolates: respectively 0.05-0.13% and 0-0.04% of the applied Diuron. At the end of the monitoring period, more residues of Diuron than oryzalin were recovered in the soil profiles: respectively 4.6-9% and 1.4-4.4%. The oryzalin residues were found mainly in the upper 10 cm of soil columns, whereas Diuron residues were present in the whole core. The mobility of both oryzalin and Diuron seems fairly well-related to soil organic carbon content; the mobility of Diuron is also related to soil texture (sand and coarse material contents). Under such experimental conditions, this study confirms that Diuron leaching, and therefore potential groundwater contamination, is greater than that of oryzalin.
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leaching of oryzalin and Diuron through undisturbed vineyard soil columns under outdoor conditions
Chemosphere, 2006Co-Authors: David Landry, Sylvie Dousset, Francis AndreuxAbstract:Field studies monitoring herbicide pollution in the vineyards of Burgundy (France) have revealed that drinking water reservoirs are contaminated with several pre-emergence herbicides. An assessment of the leaching of two such herbicides, Diuron and oryzalin, was therefore performed using lysimeters, under outdoor conditions, from May 2001 to May 2002. Four vineyard soils from Vosne-Romanee (Burgundy) were chosen along a topolithosequence: a rendosol and three calcosols. After 673 mm of rainfall, greater amounts of Diuron than oryzalin were measured in percolates: respectively 0.10-0.84% and 0.02-0.43% of applied herbicide, depending on soils. Measurements for Diuron metabolites detected greater amounts of DCPMU than DCPU in the percolates: respectively 0.05-0.13% and 0-0.04% of the applied Diuron. At the end of the monitoring period, more residues of Diuron than oryzalin were recovered in the soil profiles: respectively 4.6-9% and 1.4-4.4%. The oryzalin residues were found mainly in the upper 10 cm of soil columns, whereas Diuron residues were present in the whole core. The mobility of both oryzalin and Diuron seems fairly well-related to soil organic carbon content; the mobility of Diuron is also related to soil texture (sand and coarse material contents). Under such experimental conditions, this study confirms that Diuron leaching, and therefore potential groundwater contamination, is greater than that of oryzalin.
Esperanza Romero - One of the best experts on this subject based on the ideXlab platform.
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Multidisciplinary assessment of pesticide mitigation in soil amended with vermicomposted agroindustrial wastes
Journal of Hazardous Materials, 2016Co-Authors: Jean Manuel Castillo, Fabrice Martin-laurent, Jérémie Béguet, Esperanza RomeroAbstract:Soil organic amendment affects biotic and abiotic processes that control the fate of pesticides, but the treatment history of the soil is also relevant. These processes were assessed in a multidisciplinary study with the aim of optimizing pesticide mitigation in soils. Soil microcosms pre-treated (E2) or not with Diuron (E1) were amended with either winery (W) or olive waste (0) vermicomposts. Herbicide dissipation followed a double first-order model in El microcosms, but a single first-order model in E2. Also, Diuron persistence was longer in El than in E2 (E1-DT50 > 200 day(-1), E2-DT50 < 16 day(-1)). The genetic structure of the bacterial community was modified by both Diuron exposure and amendment. O-vermicompost increased enzymatic activities in both experiments, but Diuron-degrading genetic potential (puhB) was quantified only in E2 microcosms in accordance with reduced Diuron persistence. Therefore, O-vermicompost addition favoured the proliferation of Diuron degraders, increasing the soil Diuron-depuration capability.
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enzyme activities and Diuron persistence in soil amended with vermicompost derived from spent grape marc and treated with urea
Applied Soil Ecology, 2010Co-Authors: Esperanza Romero, Jesus D Fernandezbayo, Jean Manuel Castillo Diaz, Rogelio NogalesAbstract:Abstract Mineral fertilizers, organic amendments, and pesticides are inputs commonly used in conventional farming practices. The aim of this study was to evaluate the effects of single or combined applications of spent grape marc-vermicompost, urea, and/or Diuron on soil-enzyme activities and the persistence of this herbicide in soils with low organic carbon content. The application of vermicompost enhanced dehydrogenase (DHase) enzyme activity over time but altered soil urease activity to a very limited extent. The reduction in Diuron concentrations and the increase in DHase activity indicated that the soil microorganisms were capable of degrading the ureic herbicide. Treatment with vermicompost and Diuron had a stimulatory effect on soil microbial activity. On the whole, the application of Diuron and urea to the vermicompost-amended soil raised DHase and urease activity to maximum levels (>3 μg INTF g −1 h −1 and >47 μg NH 4 + g −1 h −1 , respectively). The application of urea to the unamended and vermicompost-amended soil decreased Diuron persistence from 18.8 and 33 d to 12.5 and 15 d, respectively. Our findings show that although vermicompost additions reduce Diuron availability, this boosts Diuron degradation when combined with urea. These additions, under different soil management conditions, minimize the bioavailability and persistence of Diuron and consequently the risk of leaching and seepage into aquifers. Compared with untreated soils, these types of treated soils could also improve agricultural sustainability and the quality of the environment.