title: Use of organic amendments as a bioremediation strategy to reduce the bioavailability of chlorpyrifos insecticide in soils. Effects on soil biology.
abstract: The sorption capacity of both an organic municipal solid waste by-product (MSW) and a cow manure (CM) in a soil polluted with chlorpyrifos, as well as its effect on soil microbial activity, and weight, reproductive parameters and glutathione-S-transferase activity of two earthworm species (Eisenia fetida and Lumbricus terrestris) were studied. Chlorpyrifos was added at the recommended application rate (5 L ha(-1); 768 mg chlorpyrifos kg(-1)) and treated with MSW at a rate of 10% and CM at a rate of 5.8% in order to apply the same amount of organic matter to the soil. An unamended polluted soil was used as control. Earthworm cocoon number, average weight of cocoon, and number of juveniles per cocoon were measured after 30 days of incubation, whereas soil enzymatic activities, earthworm weight, and glutathione-S-transferase activity of earthworms were measured after 3, 45 and 90 days. Soil enzymatic activities, reproductive and glutathione-S-transferase activity in both worms decreased in polluted soil. The inhibition percentage of soil enzymatic activities, reproductive and glutathione-S-transferase activity in both worms was lower in MSW-amended soil than for CM-amended soil. The toxic effect of chlorpyrifos on E. fetida was lowest compared to L. terrestris. This suggested that the addition of organic wastes with higher humic than fulvic acid concentration is more beneficial for remediation of soils polluted with chlorpyrifos.
authors.affiliation: Grupo de investigación Edafología Ambiental, Departamento de Cristalografía, Mineralogía y Química Agrícola, ETSIT Universidad de Sevilla, Crta de Utrera km. 1, 41013 Sevilla, Spain. mtmoral@us.es
authors.forename: Manuel
authors.initials: M
authors.lastname: Tejada
authors.forename: Isidoro
authors.initials: I
authors.lastname: Gómez
authors.forename: Marina
authors.initials: M
authors.lastname: Del Toro
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D001682:Biological Availability; D002417:Cattle; D004390:Chlorpyrifos / Q000493:pharmacokinetics*; D004787:Environmental Pollution / Q000032:analysis; D005982:Glutathione Transferase / Q000378:metabolism; D007306:Insecticides / Q000493:pharmacokinetics*; D008372:Manure; D009835:Oligochaeta / Q000187:drug effects* / Q000201:enzymology / Q000502:physiology; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000493:pharmacokinetics*; D018505:Waste Management
chemical_list: D007306:Insecticides; D008372:Manure; D012987:Soil; D012989:Soil Pollutants; D005982:Glutathione Transferase; D004390:Chlorpyrifos