Estimating the Bioaccumulation of Dioxin and Related Compounds in Aquatic Life and Associated Wildlife.

Objective/Intended Use

This project will prepare an issue paper on methods for estimating the bioaccumulation of dioxin and related compounds in aquatic life and associated wildlife, which will provide a general support document for risk assessors.

Abstract

This project will prepare an issue paper on methods for estimating the bioaccumulation of dioxin and related compounds in aquatic life and associated wildlife, which will provide a general support document for risk assessors. Risk assessors are often required to quantify or review calculations which describe the uptake of dioxins and dioxin-like compounds in plants and animals living or feeding in an aquatic environment. Such determinations become an issue at sites for which a link can be established between the concentration of one or more of these compounds in a contaminated water body and the potentially harmful amounts of these same substances taken up by members of a food chain. The issue is especially important for dioxins and dioxin-like compounds because of their capacity to increase in concentration (bioaccumulate) as they pass from one trophic level to another. This report presents information for the physical-chemical characteristics of dioxin such as hydrophobicity, lipophilicity, affinity for the aryl hydrocarbon receptor and the environmental fate of the dioxins and dioxin-like compounds. The report also contains a summary of the methodological approaches available for estimating bioconcentration factors, biota-sediment accumulation factors, and bioaccumulation factors, demonstrates the application of selected methods to dioxins and dioxin-like substances through the use of some well-known and high quality data sets, calculates BAFs and related indices from information reported in some recently published experimental studies and environmental surveys, and defines commonly used bioaccumulation terms. The information in the report should be useful to assessors seeking to evaluate the bioaccumulation of dioxins and related compounds in aquatic life.

Project Status

An external review draft has been completed. The final report will be submitted for clearance in June 2003.

Project Start Date

10/01/1999

Project Completion Date (Actual/Projected)

09/30/2003