CONCENTRATION DISTRIBUTION OF HEAVY METALS IN MANILA CLAM (RUDITAPES PHILIPPINARUM) AND POTENTIAL HEALTH RISK IN THE COASTAL AREAS OF LIAODONG BAY, CHINA

Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), and Zinc (Zn) concentrations in Manila clam from Liaodong Bay (China) were determined by inductively coupled plasma mass spectrometry. Tissue-specific bioaccumulation, geographical variability (using metal pollution indices) and health risks (using target hazard quotients and maximum daily consumption values) were assessed. Cd concentrations were high at all sampling sites, particularly S6 and S7, where it reached Category III. Other metal concentrations were high at S7 (As), S1 (Cr), S5 (Pb), and S5 and S7 (Zn). As, Cr and Cu accumulated to a higher degree in the viscera than muscles, but Cd accumulated more in muscles than viscera. Heavy metal (HM) contamination was worse in the west than that in the east. The Cd target hazard quotients were greater than 1, but the other HM target hazard quotients were less than 1 at all sites, indicating Cd posed the greatest health risks to humans The maximum daily consumption values also indicated Cd poses health risks.