Lead Accumulation in Soft Tissues and Shells of Asiatic Clams (Corbicula fluminea)

Proceedings of the 1999 Georgia Water Resources Conference, March 30 and 31, Athens, Georgia.Bivalves bioaccumulate metals and are useful as sentinel organisms for assessing the bioavailability of metal contaminants in aquatic ecosystems. Frequently, tissue metal concentrations are used by environmental monitoring studies to evaluate potential exposure and effects scenarios. However, bivalves may accumulate certain metals, such as lead, to a significant extent in shells. The purpose of this study was to evaluate the uptake and distribution of lead in the Asiatic clam (Corbicula fluminea) to determine the utility of using shell lead concentrations in environmental monitoring studies. Clams were exposed to lead (5 and 10 mg/L) in a static-renewal system for three weeks. Tissue (adductor muscle and foot) and shell lead concentrations were quantified by atomic absorption spectroscopy after three weeks of exposure and one week post-exposure. Lead accumulation in shells and tissues increased with increasing exposure concentrations. Lead accumulation in shells was approximately 76 to 89% greater than accumulation in adductor muscle tissue and 48 to 70% greater than accumulation in foot tissue. Furthermore, shell lead concentrations were not altered in depurated clams. Together, these data indicate that shells represent a primary storage site for lead in Asiatic clams and suggest that shells may represent a valuable biological material to sample in environmental monitoring studies when lead is a contaminant of concern.Sponsored and Organized by: U.S. Geological Survey, Georgia Department of Natural Resources, The University of Georgia, Georgia State University, Georgia Institute of TechnologyThis book was published by the Institute of Ecology, The University of Georgia, Athens, Georgia 30602-2202 with partial funding provided by the U.S. Department of Interior, geological Survey, through the Georgia Water Research Insttitute as authorized by the Water Research Institutes Authorization Act of 1990 (P.L. 101-397). The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of the University of Georgia or the U.S. Geological Survey or the conference sponsors