Avaliação da contaminação de cádmo e chumbo em águas, sedimentos e peixes: estudo de caso: rio Apucaraninha na terra indígena Apucarana - Pr

Abstract

The Apucarana Indigene Land (T.I.), localized on northern of Parana state, face the situation in its territories about the environmental impacts resulting from the restraining Apucaraninha river, with the Fiú reservoir building for the electric power generation. The drainage basin of the reservoir covers urban and rural areas outside the boundaries of T.I. The environmental quality of the reservoir has been questioned and a priority needs is to assess the levels of trace elements in fish routinely consumed by Indians, as these items shows hazards associated with toxic and bioaccumulative potential. In this study we carried out a preliminary assessment of the concentration of cadmium (Cd) and lead (Pb) in water and sediment samples collected in the Fiú reservoir, and the liver and muscle samples of fish species Astyanax altiparanae from stretches of the river Apucaraninha. The determination of the elements in the water samples was performed in Flame Atomic Absorption Spectrophotometer (FAAS). The Electrothermal Atomic Absorption Spectrometry (ET AAS) was used for the sediment samples, liver and muscle of fish. The results have showed water levels for Cd and Pb below the detection limit of the technique. The average concentration for Cd and Pb in sediments has presented below the level established by CONAMA Resolution No. 334/2004, where the probability is low for adverse effects to biota. In the fish sample, Cd showed higher accumulation in the liver than in muscle, whereas the greatest accumulation for Pb was found in the muscle, where the concentration found was around five times the allowed limit in fish and fish products, according to Decree No. 685/1998 of the Secretary of Health Surveillance of the Brazilian Ministry of Health. These results are worrying as the ingestion of food contaminated with these elements needs further investigations.