Methylmercury in Predatory and Non-predatory Fish Species Marketed in the Amazon Triple Frontier

This study assessed if the concentrations of methylmercury (MeHg) in predatory and non-predatory fish caught in the Upper Solimões River are safe for human consumption, according to the reference values established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). MeHg concentrations were evaluated in muscle of 5 predatory and 4 non-predatory fish species by gas chromatography with electron capture detector (GC-ECD). MeHg concentrations in predatory (0.09 mg kg^-1) and non-predatory (0.04 mg kg^-1) fish were under the safe upper limit for human consumption. The general average concentration of MeHg in these fish were 0.05 mg kg^-1. The Estimated Weekly Intake of MeHg was higher than the provisional tolerable weekly intake in both predatory and non-predatory fish, especially for women. Due to the high rates of fish consumption in the Amazon, the risk assessment based only on the concentration of MeHg in fish may not be accurate.