Dredging Research. Volume 6, Number 3. September 2003, Rapid, Sediment- Specific Indicators of Hydrophobic Organic Contaminants Bioavailability Proposed

摘要

Approximately 400 million cubic yards of sediments is dredged from U.S. ports, harbors, and waterways each year to maintain the nation's navigation system. Approximately 10 to 20 percent of this material is impacted with organic contaminants. Much of this dredged material is placed in diked confined disposal facilities. The U.S. Army Corps of Engineers would like to recycle this material for beneficial uses, and the Corps is required by the Clean Water Act to assess the potential for these contaminants to accumulate in biota. Simple models based on fugacity (e.g., the organic carbon normalized partitioning coefficient (Koc)) have been developed and are widely used to predict the partitioning of hydrophobic organic contaminants (HOC) between organic matter and organism lipid. Commonly used fugacity models assume HOC partitioning behavior is dictated by the amount of organic carbon in sediments and is independent of the quality of this organic matter. However, many publications have shown that the quality of organic carbon can greatly affect the bioavailability of HOC. Koc-based predictions of HOC partitioning behavior were compared to directly measured HOC partitioning to solid phase extraction (SPE) materials using sediments from on-going Corps dredging operations.