Freshwater Mussel,Lamellidens Marginalis(Lamarck) (Mollusca: Bivalvia: Unionidae) As an Indicator of River Pollution

Abstract

Abstract Analyses were made of heavy metals, manganese, nickel, copper, zinc and lead in water samples and soft body, shell and different tissues (gills, digestive glands, mantle and viscera) of the Unionid mussel, Lamellidens marginalis collected from two tributaries of the Cauvery river. Water samples from Station I contained higher concentrations of the metals than those from Station II. the concentration of metals in water at both stations were in the descending order: Mn > Zn > Pb > Ni > Cu. However, the concentrations of metals in the soft body were in the descending order: Zn > Mn > Pb > Ni > Cu at both stations in all size groups of mussels tested. the concentration of zinc maintained a linear relationship with the size of the mussels, but manganese showed a reverse trend. Small size (4-5 cm) mussels accumulated more manganese (105.5 μg.g−1 dry wt.) than larger ones (7-8 cm; 6.5 μg.g−1 dry wt.). Both young and old is accumulate the same level of lead, copper and nickel in the soft body. the order ...