Mercury in a widely consumed fish Micropogonias furnieri (Demarest, 1823) from four main Brazilian estuaries.

We analyzed mercury levels in the white muscular tissue of a fish (Micropogonias furnieri) originated from four Brazilian estuaries during the period between the summer 1990 and spring 1991. Mercury levels were below the maximum permissible limit established for food by the Brazilian legislation (500.0 ng.g-1 wet wt.). The measured mercury concentrations ranged from 17.4 to 266.0 ng.g-1 (wet wt.), for Guanabara Bay 19.5-252.2 ng.g-1 (wet wt.), for Sepetiba Bay 23.0-433.7 ng.g-1 (wet wt.), for Ilha Grande Bay 13.8-296.3 ng.g-1 (wet wt.) for Conceição Lagoon. Positive relationships were observed between mercury concentration in fish and the length and weight of the fishes. Weight normalized concentration showed Guanabara Bay presented the higher levels and the Conceição Lagoon presented the lowest levels. Ilha Grande Bay presented the second highest levels after Sepetiba Bay, although the former is considered a non-contaminated area.