For many years, Dow AgroSciences has worked with the Environmental Protection Agency (EPA) and other agencies to minimize the effects of its products on wildlife and the environment. All uses of pesticides, including chlorpyrifos, are carefully evaluated prior to initial registration approval and studied and monitored over time as part of the registration review process.
Testing Approaches for Pesticides
Sensitivity of chlorpyrifos to a large variety of aquatic and terrestrial wildlife has been determined under laboratory conditions, including birds, mammals, fish, water fleas, earthworms, and honeybees. For birds and mammals, effect and no effect exposures via food are determined on a short-term and long-term basis For aquatic or soil organisms, concentrations in the surrounding environment resulting in effects and no effects are determined for both short-term and long-term exposures. In addition, laboratory studies determine the ingestion or absorption of chlorpyrifos by test species and subsequent metabolism and detoxification pathways and rates.
Screening-level safety assessments involve comparing worst-case concentrations of chlorpyrifos in food sources or the surrounding environment with levels that may cause effects or no effects in wildlife. Concentrations may be estimated from modeling with laboratory data or taken from field monitoring studies. These simple assessments are often highly conservative in nature and in some cases may flag a concern and lead to the need for further refinement using more realistic but complex assessments, including field studies.
A number of field experiments have been completed to determine the potential impact of chlorpyrifos use and exposures on wildlife safety. These studies are conducted under more realistic conditions of product use and allow assessment of the response of individuals as well as that of wildlife populations and natural communities of species.