Framework for Application of the Toxicity Equivalence Methodology for Polychlorinated Dioxins, Furans and Biphenyls in Ecological Risk Assessment (External Review Draft)
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Polychlorinated dioxins (PCDDs), furans (PCDFs), and biphenyls (PCBs) are persistent contaminants found widely in the environment. Several of these compounds bioaccumulate in the tissues of fish, birds, and mammals, where they have been demonstrated to cause mortality and adverse effects on reproduction, development, and the immune system. This Framework is intended to assist EPA scientists in using a method known as the toxicity equivalence methodology to assess ecological risks from mixtures of these compounds. The Framework also informs EPA decision makers, other agencies, and the public about this methodology.
This framework is not a regulation nor is it intended to substitute for federal regulations.
As a service to reviewers, the 1997 World Health Organization database on relative potencies for PCDDs, PCDFs, and PCBs cited in the draft Framework is also provided below under Downloads. Please note that this is not an EPA database.
This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.