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Science Advisor Programs

Issue Paper on the Bioavailability and Bioaccumulation of Metals

The goal of this paper is to summarize the current and emerging state of the science supporting assessments of metal bioavailability and bioaccumulation in aquatic and terrestrial organisms and, more importantly, to identify the relevance of this science for improving current Agency practices that involve (explicitly or implicitly) metals bioavailability and bioaccumulation.

To accomplish this goal, we first introduce a conceptual model of the bioaccessibility, bioavailability and bioaccumulation processes in relation to the expression of toxicity. Given the complex and overlapping nature of these concepts as well as the different definitions and uses of these terms in scientific literature, we define a number of related terms for the purposes of this paper.

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