Analysis of Chlorpyrifos Agricultural Use in Regions of Frequent Surface Water Detections in California, USA
- 506 Downloads
Chlorpyrifos is a common surface water contaminant in California, USA. We evaluated five years of chlorpyrifos use and surface water monitoring data in California’s principal agricultural regions. Imperial County and three central coastal regions accounted for only 10 % of chlorpyrifos statewide use, but displayed consistently high aquatic benchmark exceedances (13.2 %–57.1 %). In contrast, 90 % of use occurred in Central Valley regions where only 0.6 %–6.5 % of samples exceeded aquatic benchmarks. Differences among regions are attributable to crop type, use intensity, irrigation practices and monthly application patterns. Application method did not appear to be a factor.
KeywordsChlorpyrifos Pesticide use Runoff Monitoring
The authors would like to thank Kean Goh, Sheryl Gill, David Duncan, John Sanders and Charles Andrews for their support and guidance on the work.
- California Department of Pesticide Regulation (DPR) (2005) Text of final regulations. Available online via: http://www.cdpr.ca.gov/docs/emon/dormspray/05_004final.pdf. Accessed 9 May 2012
- California Department of Pesticide Regulation (DPR) (2012a) Surface Water Protection Program Database. http://www.cdpr.ca.gov/docs/emon/surfwtr/surfdata.htm. Accessed 9 May 2012
- California Department of Pesticide Regulation (DPR) (2012b) Pesticide information portal, pesticide use report (PUR) data. Available via CDPR website: http://calpip.cdpr.ca.gov/main.cfm. Accessed 9 May 2012
- Corbin M, Daiss R, Judkins DR (2009) Risks of chlorpyrifos use to federally threatened & endangered species. USEPA office of pesticide program. Available online via: http://www.epa.gov/espp/litstatus/effects/redleg-frog/chlorpyrifos/analysis.pdf. Accessed 9 May 2012
- Larson J, Capel PD, Majewski MS (1991) Pesticides in the Hydrologic System. Ann Arbor Press, Inc. Chelsea, MIGoogle Scholar
- Spurlock, F. (2004) Analysis of recent chlorpyrifos use and surface water monitoring data. Memorandum Report California department of pesticide regulation. Environmental Monitoring Branch, Sacramento, California. Available online via: http://www.cdpr.ca.gov/docs/emon/pubs/ehapreps/fnl_chlor_analysis.pdf. Accessed 9 May 2012
- U.S. EPA (2012) Office of pesticide program’s aquatic life benchmarks. Available online via: http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_benchmark.htm#benchmarks. Accessed 9 May 2012
- USDA (2009) USDA natural resources conservation service. Available via NRCS website: http://www.ca.nrcs.usda.gov/features/calwater/. Accessed 9 May 2012