PARENT SESSION
IP01 - Sediment Quality Guidelines
Chair: Pawlisz, Andrew1, 1 The Cadmus Group, Ottawa, ON
8:00 AM to 12:00 PM - Sunday, 17 November 2002
Room Room 150 G
(IP10) A Framework for Development of Tissue Residue Benchmarks for Estimating Risk Associated with Contaminated Sediments .
Pawlisz, Andrew*,1, Steevens, Jeffery2, Reiss, Mark3, 1 The Cadmus Group, Ottawa, Ontario, Canada2 ERDC-EL, U.S. Army Corps of Engineers, Vicksburg, MS3 Division of Environmental Planning and Protection, U.S. EPA, Region 2, New York, NY, USA
ABSTRACT- The tissue residue-based approach for evaluating the potential for adverse effects of pollutants in aquatic biota has become a reality for many ecorisk, policy, and contaminated site remediation practitioners. This is because an internal dose of a contaminant is a much better surrogate for the dose at the toxicological site of action than the external or the ambient dose. The decision of whether a tissue residue of a contaminant has the potential to have an adverse effect must be based on data that link adverse effects to certain residue levels. Traditional benchmarks serve that purpose. However, they are no more than single point estimates. Our framework proposes to report benchmarks as distributions rather than as single point estimates. The main advantage of having distributions of effect-based tissue residues is that the user will be able to determine the probabilities of a particular adverse effect occurring. As a result, the user will have a much more powerful way for judging risk than the current bimodal exceedance or non-exceedance model with an unknown likelihood of occurence. Our framework makes use of information contained in existing literature to present effects-based tissue residues as point estimates and statistical distributions. This transformation increases the utility of the presented information by allowing explicit statements of probability of an adverse effect occurring, reporting of multiple effects endpoints, addressing mixture toxicity, and species or chemical-group specific analysis of tissue residue data.
Key words: Tissue Residue, Benchmarks, Framework, Contaminated Sediments