Using enriched stable isotope technique to study Cu bioaccumulation and bioavailability in Corbicula fluminea from Taihu Lake, China

In this study, we measured trace metals (Cd, Cr, Cu, Ni, Pb, and Zn) in water and sediment from representative sites of Taihu Lake, with focus on the analysis of trace metal accumulation in Corbicula fluminea (bivalve). The results showed that the quality of water in Taihu Lake was generally good and the correlation was not found between Cu bioaccumulation in C. fluminea and the concentration in water and sediment. Thus, using the stable isotope tracer method, we studied Cu uptake from the water phase, the assimilation of Cu from the food phase, and the efflux of Cu in vivo by C. fluminea. The result revealed that this species exhibited a relatively lower efflux rate constant of Cu compared with other zoobenthos species. Using a simple bioenergetics-based kinetic model, Cu concentrations in the C. fluminea were calculated with the measured efflux rate. We put forward a novel method, which was taking the influence of biological kinetic on metal bioaccumulation into account to explain the field survey data.