Biomixtures constitute the biologically active part of biopurification systems（BPS）, which are used to treat pesticide-containing wastewater. The aim of this work was to determine whether co-application of chlorpyri...Biomixtures constitute the biologically active part of biopurification systems（BPS）, which are used to treat pesticide-containing wastewater. The aim of this work was to determine whether co-application of chlorpyrifos（CLP） affects the removal of carbofuran（CFN）（both insecticide/nematicides） in a coconut fiber–compost–soil biomixture（FCS biomixture）, after aging or previous exposure to CFN. Removal of CFN and two of its transformation products（3-hydroxycarbofuran and 3-ketocarbofuran） was enhanced in pre-exposed biomixtures in comparison to aged biomixtures. The co-application of CLP did not affect CFN removal, which suggests that CLP does not inhibit microbial populations in charge of CFN transformation.Contrary to the removal behavior, mineralization of radiolabeled14C-pesticides showed higher mineralization rates of CFN in aged biomixtures（with respect to freshly prepared or pre-exposed biomixtures）. In the case of CLP, mineralization was favored in freshly prepared biomixtures, which could be ascribed to high sorption during aging and microbial inhibition by CFN in pre-exposure. Regardless of removal and mineralization results, toxicological assays revealed a steep decrease in the acute toxicity of the matrix on the microcrustacean Daphnia magna（over 97%） after 8 days of treatment of individual pesticides or the mixture CFN/CLP.Results suggest that FCS biomixtures are suitable to be used in BPS for the treatment of wastewater in fields where both pesticides are employed.展开更多
基金supported by the Vicerectorship of Research,University of Costa Rica(projects 802-B2-046 and 802-B4-503)the Costa Rican Ministry of Science,Technology and Telecommunications,MICITT(project FI-093-13)the Joint FAO/IAEA project TC COS5/029
文摘Biomixtures constitute the biologically active part of biopurification systems（BPS）, which are used to treat pesticide-containing wastewater. The aim of this work was to determine whether co-application of chlorpyrifos（CLP） affects the removal of carbofuran（CFN）（both insecticide/nematicides） in a coconut fiber–compost–soil biomixture（FCS biomixture）, after aging or previous exposure to CFN. Removal of CFN and two of its transformation products（3-hydroxycarbofuran and 3-ketocarbofuran） was enhanced in pre-exposed biomixtures in comparison to aged biomixtures. The co-application of CLP did not affect CFN removal, which suggests that CLP does not inhibit microbial populations in charge of CFN transformation.Contrary to the removal behavior, mineralization of radiolabeled14C-pesticides showed higher mineralization rates of CFN in aged biomixtures（with respect to freshly prepared or pre-exposed biomixtures）. In the case of CLP, mineralization was favored in freshly prepared biomixtures, which could be ascribed to high sorption during aging and microbial inhibition by CFN in pre-exposure. Regardless of removal and mineralization results, toxicological assays revealed a steep decrease in the acute toxicity of the matrix on the microcrustacean Daphnia magna（over 97%） after 8 days of treatment of individual pesticides or the mixture CFN/CLP.Results suggest that FCS biomixtures are suitable to be used in BPS for the treatment of wastewater in fields where both pesticides are employed.
