Biota−Sediment Accumulation Factors for Polychlorinated Biphenyls

Sep 17, 2004 - (24) have determined, by radionuclide dating techniques, sedimentation rates for the Lake Michigan ecosystem using sediments taken conc...
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Environ. Sci. Technol. 2004, 38, 5297-5305

Biota-Sediment Accumulation Factors for Polychlorinated Biphenyls, Dibenzo-p-dioxins, and Dibenzofurans in Southern Lake Michigan Lake Trout (Salvelinus namaycush) LAWRENCE P. BURKHARD,* PHILIP M. COOK, AND MARTA T. LUKASEWYCZ Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, U.S. Environmental Protection Agency, 6201 Congdon Boulevard, Duluth, Minnesota 55804

quality criteria and standards for the protection of human health (8), and (v) assessing relative bioaccumulation differences among individual chemicals (9). There are some distinct advantages of using BSAFs (in comparison to BAFs) for predicting chemical residues in fish. Measurement of concentrations of most highly hydrophobic nonionic organic chemicals in sediment can be performed fairly easily. Consequently, with an appropriate BSAF, chemical residues in fish can be readily predicted from a measured or predicted chemical concentration in the reference sediment. In contrast, measurements in water can be difficult due to temporal fluctuations of the chemical concentrations, which are also often below method detection limits. Because concentrations of highly hydrophobic nonionic organic chemicals are temporally more stable in both fish and sediments, BSAFs for fish better integrate fluctuating exposure conditions than do BAFs (10). The BSAF has been defined (11) as

BSAF )

A set of high-quality, age-specific biota-sediment accumulation factors (BSAFs) for polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) have been determined from concentrations measured with high-resolution gas chromatography/high-resolution mass spectrometry, by use of the 13C isotopic dilution technique, in lake trout and surficial (0-2 cm) sediment samples from southern Lake Michigan. BSAFs ranged from