Bioaccumulation of lead (Pb) and remediation by calcium chelation therapy in the gills and mantle of freshwater bivalve, Lamellidens marginalis

The paper aims at bioaccumulation of lead (Pb) and removal of accumulated lead by calcium chelation therapy. This has been studied in the gill and mantle of the freshwater bivalve, Lamellidens marginalis. The bivalves were exposed to 1/10^th of LC₅₀ dose of lead acetate, different doses i.e. as 28, 56 and 84 ppm calcium acetate of and combinations of lead acetate and calcium acetate for 8 days and 16 days period. It was observed that, there was more accumulation of Pb in gills as compared to mantle. In 8 days Pb treated group accumulation of Pb in gill was 3.300 mg/ml and after 16 days exposure it was 4.129 mg/ml. It was observed that this accumulation was decreased at 56 and 84 ppm calcium treated groups for 8 days and 16 days. Similarly, in mantle Pb accumulation was 2.381 and 2.938 mg/ml on 8 days and 16 days respectively. This accumulation was decreased at 56 and 84 ppm calcium treated groups which are 1.870 and 1.581mg/ml for 8 days and 1.20 and 1.225 for 16 days mg/ml. The study also suggests that the accumulation of Pb was directly proportional to the exposure time. With increase in calcium concentration, the concentration of Pb was decreased.