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Common Effects Methodology for Pesticides

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Background on Common Effects Methodology for Pesticides

Both EPA's National Pesticide and National Water Programs assess the effects of pesticides on aquatic ecosystems using approaches that afford a high degree of protection for aquatic life. Both approaches were developed with high quality data using rigorously peer-reviewed assessment methodologies. In characterizing pesticide effects, both programs consider acute effects as well as chronic and sub-lethal effects on growth, survival, and reproduction in their assessments. 

Stakeholders have identified a need for consistent and timely federal input that will allow EPA, states, tribes and the public to gauge whether pesticides represent a concern for aquatic life, for example, based on water monitoring results. In response, EPA has been exploring how to build on the substantial high quality science developed under both programs to develop additional tools and approaches to support a consistent and common set of effects characterization methods using best available information. EPA's goal is to develop tools and approaches that:

  • Continue to be based upon sound science and utilize the best available data
  • Are legally defensible under our statutory mandates
  • Will be based upon methodologies that are as consistent and practical as possible
  • Are implementable at the federal and state level
  • Are developed as quickly and efficiently as possible
  • Reflect stakeholder input and comments

Current Activities for Developing Common Effects Methodology for Pesticides

A FIFRA (Federal insecticide, Fungicide, and Rodenticide Act) Scientific Advisory Panel (SAP) meeting was held in late January 2012.  The FIFRA SAP is composed of biologists, statisticians, toxicologists and other experts who provide independent scientific advice to EPA on a wide-range of health and safety issues related to pesticides. The SAP reviewed EPA analyses regarding potential approaches to develop a Common Effects Methodology. The SAP review was highly favorable, and the SAP made a number of recommendations for EPA to move forward with their approach in a report issued in April 2012. 

The six EPA reports that were discussed at the SAP meeting were developed by EPA's office of Research and Development in conjunction with the Office of Water and Office of Pesticide Programs:

  • White Paper
  • Potential Use of Predictive Toxicology Tools in Characterizing Effects of Chemical Stressors to Aquatic Animals
  • Analysis of Species Sensitivity Distribution (SSDs) for Estimation of Acute Hazrd Concentrations to Aquati Animals
  • Extrapolation Factors (EFs) for Derivation of Acute Aquatic Life hC5s: Emphasis on Acetylcholinesterase Inhibitors
  • Analysis of Chronic Toxicity Data and Acute to chronic Rations (ACRs) in Support of Deriving Chronic HC5s: Acetylcholinesterase Inhibitors
  • Methods for Estimating Aquatic Plan Community Hazard Concentrations for Pesticide Effects

Common Effects Activities: 2009-2011

Regional Stakeholder Meeting January 11 -22, 2010

EPA held six regional public meetings in January 2010 to solicit stakeholder input on its initial thinking regarding a commono effects assessment process and the scoe and content of future white papers.  The meetings were held in the following EPA regions: Regions 2, 4, 5, 7, 9 (Oakland, CA) and 10.

The following five presentations for the regional meetings laid out the need for this effort, the process EPA would use, and the agency’s initial thinking on major issues regarding common effects assessments using available data in an effort to solicit stakeholder input on EPA's initial thinking regarding a common effects assessment process.

National Stakeholder Meeting December 1, 2010

EPA conducted a national stakeholders meeting on December 1, 2010 to solicit input on methods being evaluated by the Water and pesticide Programs with the support of the Office of Research and Development (ORD), to characterize effects from pesticides on fish, other aquatic organisms, and aquatic plants in aquatic ecosystems. This meeting built on the meetings held at EPA Regional Offices around the county in January 2010.  Comments solicited during the comment period were considered by EPA in its development of white papers that expanded on the Agency’s initial thinking. 

At the public meeting in Washington, DC, EPA presented three white papers that explored the following topics:

These white papers also described how the potential new tools, methods, and analytical approaches may be used by the Agency, state pesticide and water quality agencies, and other stakeholders to gauge whether pesticides represent a concern for aquatic life.  Below are copies of the individual white paper presentations from the national stakeholder meeting.

Activities in 2009

OPP-OW Common Effects Assessment Methodology Toward a Common Effects Characterization Methodology Scoping Document (April 2009)

This document provides the background for a proposal to derive a common effects characterization methodology for use in ecological assessments of chemicals by EPA to meet the mandates of the Clean Water Act (CWA) and the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

The resulting framework will integrate the Agency's aquatic effects characterization methods and provide a common basis for achieving the water quality protection goals established under the CWA and FIFRA statutes. The framework will also enable the Agency to more transparently communicate to States, the public and other stakeholders how approaches used by EPA offices to characterize effects in aquatic ecosystems are integrated and implemented.

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