The Environmental Protection Agency Thursday released for public comment two draft guidance documents regarding pesticide spray drift.
The two documents are posted on the Federal Register under Docket EPA-HQ-OPP-2013-0676-0001.
"EPA is seeking to strengthen its protections for people and the environment from exposure to pesticides that drift from fields to nearby areas, including homes, schools and playgrounds," the agency wrote in an announcement.
Together, the two documents describe how off-site spray drift will be evaluated for ecological and human health risk assessments for pesticides.
The first draft document, Ecological and Drinking Water Assessment Guidance, provides information on estimating spray drift fractions of liquid sprays in ecological or drinking water settings.
It will also provide guidance for estimating distances from the treated field where adverse effects may be observed due to exposure to spray drift. The draft guidance also provides default assumptions for modeling inputs to use when estimating spray drift in land or water assessments.
The Residential Exposure document describes a screening approach for defining when assessments are needed and the methodology for estimating risks for indirect exposures to pesticide drift.
An example of indirect exposure could be children playing on a lawn that has pesticide residues that drifted from a nearby treated field, EPA said. The draft guidance describes when risk assessments for spray drift are generally needed, and also provides the modeling inputs needed to complete the exposure and risk assessments.
EPA expects the values for spray drift fractions to provide "realistic exposure and risk estimates" for both ecological and human health testing.
The agency said the new guidance will improve consistency within EPA, as well as with other federal agencies and international regulatory partners that rely on predicted spray drift values. They will also add to routine assessments that evaluate risk on workers who apply pesticides, risks from treated food and consumers who use pesticides, EPA added.
The 60-day public comment period will close on March 31, 2014. Following the public comment period, EPA will analyze the comments, make appropriate modifications to these policies and finalize them, a statement said.