Elevated mercury levels in people from Lake Murray, Western Province.

The people of Lake Murray, Western Province, Papua New Guinea are chronically exposed to methylmercury through fish consumption. In a study of 114 volunteers from the area, the mean methylmercury concentration in hair was 15.5 mg/kg (range 3.2--50.5). The main source of methylmercury is barramundi (Lates calcarifer) caught in the Lake. For nearby control groups having similar and much lower levels of fish consumption, the mean methylmercury levels in hair were 6.4 mg/kg (range 0.62--25.7) and 2.4 mg/kg (range 0.33--9.0) respectively. No significant correlations were found between methylmercury concentrations in hair and age or sex in any of the three populations.