Methyl mercury, total mercury, and selenium in snapper from two areas of the New South Wales coast, Australia

Abstract

The muscle tissue of snapper ( Chrysophrys auratus: Sparidae) from two areas of the New South Wales coast was analysed for methyl mercury, total mercury and selenium concentrations (134 samples from the Sydney area and 186 samples from the Nowra area, about 120 km to the south of Sydney). The Sydney snapper ranged from 0.08 to 1.66 mg kg −1 total mercury (mean 0.32 mg kg −1), while the Nowra snapper ranged from 0.01 to 0.78 mg kg −1 total Hg (mean 0.11 mg kg −1). These latter results appear anomalously low relative to other studies in Australia and New Zealand. Methyl mercury averaged 94.7% of the total mercury content of the Sydney snapper, and 91.3% for the Nowra snapper. The concentrations of selenium in the muscle tissues of snapper from both areas were similar and did not increase with increasing mercury concentrations. The highest selenium concentration was 0.85 mg kg −1.