Cadmium and lead in tissues of scallops from Port Phillip Bay, Australia

Levels of Cd and Pb in adductor muscle, gonad and other tissues (i.e. viscera, mantle and gill) of the scallop (Pecten alba) collected from four sites of Port Phillip Bay, Australia were determined. Cd in gonad and other tissues (3.8 ± 0.1 and 3.76 ± 0.69 μg/g dry wt. respectively) were similar but significantly higher than that in the adductor muscle (2.71 ± 0.3 μg/g dry wt.). Pb in gonad and other tissues (18.75 ± 3.88, 14.06 ± 0.72 μg/g dry wt. respectively) were also significantly higher than that in the adductor muscle (5.54 ± 0.78 μg/g dry wt.). The results indicated that Cd and Pb are mainly sequestered in gonads and other tissues but not adductor muscle. The mean concentration of Cd in all tissues from all sites were under the Australian statutory limit. Although levels of Pb in adductor muscle from all sites were also below the limit, levels of Pb in edible parts (gonads and adductor muscle) of scallops from Williamstown and Frankston were over the Australian health standard. The level of Pb was 2.5 to 4.5 times higher than that of Cd in the same tissue type. Concentrations of both metals in scallops tend to decrease from north to south and east-west, and correlated with known point source discharges in the catchment area of the Bay.