BIOACCUMULATION OF HEAVY-METALS IN FLORA AND FAUNA OF HOOGHLY ESTUARY, EAST-COAST OF INDIA

Spectroscopic determinations of Fe, Zn, Mn, Cu, Co and Ni were carried out in 23 organisms including seaweeds, zooplankters, molluscs and fi shes from Hooghly estuary at the confluence of Bay of Bengal. Seaweeds and gastropods were more efficient in accumulating levels while zoopl ankters bivalves and fishes showed intermediate levels. Analyses were performed on the sediment, water and on the individual dissected organ s of a mussel, oyster and teleost fish. Bioaccumulation of Fe, Zn, Mn and Cu in the soft body parts (gills, mantle, liver etc.) of the three species showed a high degree of organ specificity in some cases. Majo r sources of the micropollutants include natural weathering, catchment runoff, urban and industrial discharges that may pose an ecological r isk to the local estuarine ecosystem.