Heavy metals (Cd, Pb, Cu, Zn) concentrations in edible bivalves harvested from Northern Coast of Central Java, Indonesia

This study measured the concentration of Cd, Pb, Cu and Zn in bivalves captured from the northern coast of Central Java, Indonesia. We also evaluated the hazard level posed by the metals in relation to the maximum acceptable limit (MAL) for human consumption and to estimate the weekly intake and compare it with the provisional tolerable weekly intake. The highest Cd levels were recorded in Amusium pleuronectes (16.32 mg Cd/kg) and the lowest levels of Cd were observed in Perna viridis (0.18 mg Cd/kg). A. granosa contained the highest level of Pb (9.050 mg Pb/kg) and P. viridis contained the lowest level of Pb (1.07mg Pb/kg). The lowest Cu level was observed in A. granosa (1.49 mg Cu/kg) and the highest Cu level was noted in C. gigas (86.21 mg Cu/kg). The levels of Zn in all species were relatively higher compared to other metals, ranged from 33.56 to 846.81 mg Zn/kg. The Cd level in bivalves was below the MAL of WHO and FAO (2 mg/kg), except in A. pleuronectes from Tegal city. The level of Pb in bivalves was exceeded the MAL value of the various existing authorities. Cu level in C. gigas (59.2 mg Cu/kg) exceeded the MAL of Indonesian authority and WHO. Zn levels in C. gigas, A. pleuronectes and A. granosa exceeded the MAL of various authorities. In order to avoid the impact of metals on people health, then safely weight of bivalves were allowed to be consumed were 0.10 kg/week for A. granosa, 0.10 kg/week for C. gigas, 0.16 kg/week for M. lyrata, 0.36 kg.week for P. viridis and 0.03 kg/week for A. pleuronectes.