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Endangered Species

Ecological Risk Assessment Process under the Endangered Species Act

This document provides an overview of the Environmental Protection Agency’s (EPA) ecological risk assessment process for the evaluation of potential risk to endangered and threatened (listed) species from exposure to pesticides. The assessments described in this document are conducted by the Office of Pesticide Programs (OPP).

Organized into eight sections and two appendices, this document begins with a description of the purpose and organization of the document (Section I).

It continues with a brief overview of the statutory framework under which OPP operates (Section II), followed by a discussion of OPP’s mission and organizational structure, and basic information about OPP’s regulatory processes (Section III).

Section III also acknowledges the importance of evaluating regulatory actions for their potential impact to listed species and briefly describes the steps being taken to ensure that listed species concerns are addressed.

Section IV provides an overview of the Environmental Fate and Effects Division (EFED), which conducts most of the initial screening-level assessments to evaluate the potential impact of pesticides on non-target species, including listed species. This section addresses EFED’s procedures, data requirements, and processes to support the development of ecological assessments based on sound science.

Section V provides a comprehensive review of EFED’s screening-level assessment process, which is based on risk assessment procedures outlined in guidance documents and standard evaluation procedures.

If a pesticide is determined to potentially impact listed species, a species-specific assessment is conducted, which is described in Section VI.  Sections V and VI summarize the screening-level and species-specific assessments that are generally conducted in OPP. It should be noted, however, that the ecological risk assessment process within OPP may, on a case-by-case basis, incorporate additional methodologies, models, and lines of evidence that are technically appropriate for risk management objectives. Examples of additional information and methodologies include monitoring and incident data and evaluation of routes of exposure not routinely considered, but suggested by other lines of evidence.

Finally, the document concludes with a list of support documents (Section VII), references (Section VIII), and appendices. 

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