Abstract
The objective of this work was to evaluate the effects of chlorpyrifos on earthworms and on soil functional parameters. An integrated laboratory-field study was performed in a wheat field in Argentina, sprayed with chlorpyrifos at two recommended application rates (240 or 960 g ha-1 style='vertical-align:baseline'> a.i.). Laboratory tests included neutral red retention time, comet assay (single cell gel electrophoresis), and avoidance behavior, each using the earthworm Eisenia andrei exposed in soil collected 1 or 14 days after pesticide application, and the bait-lamina test. Field tests assessed organic matter breakdown using the litterbag and bait-lamina assays. Earthworm populations in the field were assessed using formalin application and hand-sorting. The neutral red retention time and comet assays were sensitive biomarkers to the effects of chlorpyrifos on the earthworm E. andrei; however, the earthworm avoidance test was not sufficiently robust to assess these effects. Feeding activity of soil biota, assessed by the bait lamina test, was significantly inhibited by chlorpyrifos after 97 days, but recovered by the 118th day of the test. Litterbag test showed no significant differences in comparison to controls. Earthworm abundance in the field was too low to adequately test the sensitivity of this assessment endpoint.
Highlights
It is increasingly recognized that the protection of soils and their inherent communities must become a primary goal of environmental policy worldwide (Römbke et al, 2005; Filser et al, 2008).Chlorpyrifos (O,O-diethyl-O-3,5,6-trichloro-2-pyridyl phosphorothioate), a broad spectrum systemic organophosphorus anticholinesterase insecticide, is widely used in Argentina in direct soil application for the control of agricultural pests.Pesq. agropec. bras., Brasília, v.44, n.8, p.874-880, ago. 2009The toxicity of pesticides to soil organisms depends on the compound bioavailability, which is affected by the physicochemical properties of the compound and the soil, and by the uptake routes of exposed organisms
Laboratory tests included neutral red retention time, comet assay, and avoidance behavior, each using the earthworm Eisenia andrei exposed in soil collected 1 or 14 days after pesticide application, and the bait-lamina test
Litterbag test showed no significant differences in comparison to controls
Summary
It is increasingly recognized that the protection of soils and their inherent communities must become a primary goal of environmental policy worldwide (Römbke et al, 2005; Filser et al, 2008).Chlorpyrifos (O,O-diethyl-O-3,5,6-trichloro-2-pyridyl phosphorothioate), a broad spectrum systemic organophosphorus anticholinesterase insecticide, is widely used in Argentina in direct soil application for the control of agricultural pests.Pesq. agropec. bras., Brasília, v.44, n.8, p.874-880, ago. 2009The toxicity of pesticides to soil organisms depends on the compound bioavailability, which is affected by the physicochemical properties of the compound and the soil, and by the uptake routes of exposed organisms. It is increasingly recognized that the protection of soils and their inherent communities must become a primary goal of environmental policy worldwide (Römbke et al, 2005; Filser et al, 2008). Ecotoxicity studies can benefit from using experimental designs that improve data relevance for local exposure conditions in the field (Yu et al, 2006; Filser et al, 2008). Due to this complexity, assessment of the risks for soil organisms cannot rely exclusively on chemical analysis. In-vivo assays using sentinel species provide a more reliable assessment of toxicity because they are more representative of the natural soil conditions
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
