Toxicity Testing and Ecological Risk Assessment Guidance for Benthic Invertebrates

Whole sediment toxicity testing is now being routinely required as part of pesticide registration actions (registration review, new pesticide registrations).

The following documents include guidance, a case study and attachments used together as the current guidance to EFED ecological risk assessors on when to require whole sediment toxicity tests and how to integrate sediment toxicity tests results into EFED ecological risk assessments. This guidance document was developed by the EFED sediment toxicity workgroup over the past several years and incorporates input from multiple EFED technical teams, senior scientists and management team briefings. Elements of this guidance have also been presented at international scientific meetings including the Society of Environmental Toxicology and Chemistry (SETAC) and the European Chemicals Agency (ECHA). Importantly, this guidance is intended to support interpretation of the sediment toxicity testing requirements set forth in 40 CFR Part 158 (Subpart G) and is not intended as a replacement or alteration of these regulations.

• Guidance and Signed Memo (pdf) (986.19 KB)
  Guidance document for when and how to integrate sediment toxicity test results in ecological risk assessments.
• Case Study: USEPA Benthic Invertebrate Risk Assessment for Endosulfan (pdf) (1.42 MB)
  The primary purpose of this case study is to illustrate the methods and data considered by the U.S. Environmental Protection Agency’s (USEPA), Office of Pesticide Programs (OPP) in assessing pesticide risks to benthic invertebrates based on its recent environmental fate and ecological risk assessment for the insecticide, endosulfan.
• Attachment 2. How to obtain sediment EECs from pe5 and Validation of Equation 1 and Alternatives to Estimating the Chemical Concentration in Sediment on a Dry Weight Basis (pdf) (595.93 KB)
  Instructions on using PRZM/EXAMs to obtain sediment EECs.
• Attachment 3. Output Files Used in Validation of Equation 1 Sediment Calculations (pdf) (207.01 KB)
  Output files that were used to validate Equation 1 of the Sediment Calculations as mentioned in Attachment 2 on this page.