Total Mercury in Three Fish Species Sold in a Metro Manila Public Market: Monitoring and Health Risk Assessment

The total mercury concentrations in bangus or milkfish (Chanos chanos Forskal), tilapia (Oreochromis niloticus) and galunggong or round scad (Decapterus spp.) purchased from a local market in Metro Manila from 5 August to 20 October 2004 were determined by cold vapor atomic absorption spectrophotometry. The ranges of total mercury concentrations observed from about 30 composite test samples for each fish species were 0.0060 to 0.015 mg kg-1 (wet weight) for bangus, 0.0041 to 0.017 mg kg-1 (wet weight) for tilapia and 0.014 to 0.05 mg kg-1 (wet weight) for galunggong. Risk assessment for neurological effects associated with the consumption of the fish species with the highest concentration of mercury (0.05 mg kg-1 for galunggong) was done. The calculated daily dose of total mercury of 0.06 µg d-1 kg-1 body weight indicates that consumption of any one or any combination of bangus, tilapia, and galunggong sold in Nepa-Q-Mart from August 5 to October 20 in 2004 does not entail risk of adverse neurological effects