A Model for Bioaccumulation of Metals in Crassostrea virginica from Apalachicola Bay, Florida

Abstract

Kinetics of bioaccumulation of the trace metals (Cd and Zn) by C. virginica were investigated in this study. A computer program, Oyster Bioaccumulation Model (OBM), was developed to simulate the accumulation of the metals from both dissolved (water column) and particulate (food) phases by C. virginica. The model is based on two main attributes: (1) the oyster biological characteristics such as gill morphometry, feeding growth rate, respiration rate and lipid composition and (2) the physicochemical properties of metals, which include aqueous diffusivity and partition coefficients. For some data from Chesapeake bay, simulation results compared well with field results. Predicted Bioaccumulation Factor (BAF) parameters (1.5 x 10⁴ for Cd and 6.6 x 10⁴ for Zn) for Apalachicola Bay show that elemental concentrations in C. virginica are up to 4 orders of magnitude greater that that of the water column. Furthermore, the model is shown to be flexible enough to be utilized in other estuaries.