Determinação de metais no sedimento da foz do rio Ocoy - tributário do Lago de Itaipu - PR

Abstract

In this study, the concentration of metals, together with analysis of physical and chemical parameters in sediment from the mouth of the River Ocoy, tributary of Lake Itaipu, and the identification of possible sources of contamination. Samples were collected at three points along the six km upstream the river mouth Ocoy, in São Miguel do Iguacu. Parameters such as pH, total phosphate, total carbon and total organic matter. Measurements of Cu, Mn and Zn were performed by FAAS and Fe gravimetrically. The results showed a small spatial variation in metal concentrations were between t 422 and 474 for Cu; 867 and 130 for Mn and Zn between 930 and 1650 (in mg.Kg-1). The iron levels are near the limit of AET (220,000 in mg.Kg-1). As the international criteria for sediment quality adopted by NOAA, in all points the levels of these ions are above the PEL, probable effects levels, indicating anthropogenic contributions. The concentrations of total phosphate link to anthropogenic sources such as sewage and agriculture, however, based on CONAMA 344, the figures do not indicate a high trophic level to the environment.