An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Risk Assessment

Ecotox Thresholds 1996

This bulletin provides an overview of the development and use of Ecotox Threshold (ET) benchmark values in Superfund ecological risk assessments (ERAs)

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.

Ecotox Thresholds 1996 (PDF)(12 pp, 131 K)
This bulletin provides an overview of the development and use of Ecotox Threshold (ET) benchmark values in Superfund ecological risk assessments (ERAs)