HEAVY-METAL POLLUTION ASSESSMENT IN THE COASTAL LAGOONS OF JACAREPAGUA, RIO-DE-JANEIRO, BRAZIL

The Jacarepagua lagoon receives the waste from 239 industries and dome stic sewage. Bottom sediment analysis revealed that metal pollution is not spread over the lagoons but restricted to the discharge areas of the main metal-carrier rivers. Metal concentrations in superficial wat er showed the following concentrations values in ng/ml: Zn, 9.63 +/- 3 .59; Pb, 0.61 +/- 0.43; Cu, 0.94 +/- 0.45; Mn, 12.7 +/- 8.0. Metal con centration in fish (average of seven different species) presented the following results, in mg/kg wet weight: Cr, 0.08 +/- 0.01; Cu, 0.4 +/- 0.15; Zn, 4.6 +/- 3.4; Fe, 2.4 +/- 1.3; Mn, 0.4 +/- 0.3. These result s imply, considering fish consumption rate and the RfD (USEPA Referenc e Dose), that the local population is not exposed to undue health risk s. Metal concentrations in the water may, however, increase due to the ir dissolution induced by pH and redox changes in the sediments.