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Endangered Species

Biological Evaluation Chapters for Chlorpyrifos ESA Assessment

EPA has finalized the Biological Evaluation for chlorpyrifos. The final evaluation is based on interim methods developed in conjunction with Fish and Wildlife Service and National Marine Fisheries Service in response to the National Academy of Science report on assessing risks to threatened and endangered species from pesticides.

Response to Comments on the Biological Evaluations for Chlorpyrifos, Diazinon and Malathion (PDF) (20 pp, 978 K,  About PDF)

On this page:

Chlorpyrifos Executive Summary for ESA Assessment (DOCX)(4 pp, 32 K)

Chapter 1:  Chlorpyrifos Problem Formulation for ESA Assessment (DOCX)(58 pp, 1.21MB)

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Chapter 2: Chlorpyrifos Effects Characterization for ESA Assessment (DOCX)(268 pp, 6.74 MB)

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Chapter 3:  Chlorpyrifos Exposure Characterization for ESA Assessment (DOCX) (53 pp, 1.45 MB)

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Chapter 4: Chlorpyrifos Effects Determinations for ESA Assessment (DOCX)(45 pp, 151 K)

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