PARENT SESSION
WP4b Pesticide Risk Assessment - Perspectives for the Future. - A discussion Session.
4:30 PM to 6:30 PM, Wednesday, 09 May 2001
Session Chair: A. Hart
Room 4

(384) A New Approach to Ecological Risk Assessment in the US EPA's Office of Pesticide Programs.

Gallagher, Kathryn¹, Sunzenauer, Ingrid¹, Fite, Edward¹, Odenkirchen, Edward¹, Touart, Leslie¹, Barry, Timothy¹, Urban, Douglas¹, Rexrode, Miachel¹, Lin, James¹, Irene, Stephanie¹, ¹

ABSTRACT- The EPA's Office of Pesticide Programs is implementing a new tiered process for conducting ecological risk assessments, which will be used under the FIFRA regulatory framework. This approach will include probabilistic tools and methods at the more refined, higher levels (tiers) to provide information regarding the probability and magnitude of potential effects. This new process will be used to quantify and better characterize the impact of pesticides on non-target terrestrial and aquatic organisms. The results of these analyses will be used by risk management divisions in decision-making. Under this new tiered approach, screening level (deterministic) assessments are first conducted and are generally based on conservative assumptions and generic data. More complex probabilistic assessments, representing increasingly realistic biological and exposure scenarios, are performed for those pesticides judged at the screening level to potentially pose the most serious risk and that are believed to require further characterization to determine appropriate regulatory action. Goals for implementation include developing approaches for refined assessments to account for the broad spectrum of responses to pesticide exposure; more realistically reflecting actual use scenarios and field conditions; building upon existing data requirements for registration; utilizing existing databases and if needed, creating new ones from existing data sources; focusing additional data requirements on reducing key areas of uncertainty; and conducting higher level assessments on pesticides posing the greatest concern. Implementation of this approach to higher level assessments has begun on a case-by-case basis, concurrent with the development of higher level tools and methods for use in future risk assessments.

Key words: Pesticides, Probabilistic Assessment, US EPA