TO STUDY ACCUMULATION OF HEAVY METALS As, Cd, Pb, AND Hg IN BIVALVES FROM NATURAL ENVIRONMENT

Abstract

The aim ofthis study is to assess the relationship between concentration of heavy metals (Cd, Pb, As, Hg) in the soft tissue of mussel and elemental contents in the surroundingenvironment such as water column, suspended solid (SS) , sediment in Can Thanh bay of CanGio province of Ho Chi Minh City.The results indicated heavy metals in the water is lowest with content 5.1 ppb for Pb, 13.6 ppb for As, 1.2 ppb for Cd and Hg not found. Heavy metalsin the suspended solid are higher than heavy metals in the water and especialy of Pb insuspended solid higher than content of Pb in sediment (23.3 ppm for SS and 14.4 ppm forsediment). Bioavailability of heavy metals in sediment also indicated that distribution of heavymetals in organic -sulphide phase higher than other phase (carbonate, water phase). Theseobservations confirmed the fact that metals in the suspended solid and organic - sulfide phaseare more bioavailable to mussels and they more accumulate metals than other species. Howeverthe distribition of metals in body of mussels is not similar, concentrations of Cd and Pb in thedigestive system are higher than those in the soft tissue. Therefore bivalve can be used as good indicators of heavy metals in the aquatic system.