Análise de elementos potencialmente tóxicos em ambientes aquáticos da Floresta Nacional de Ipanema

Abstract

Potentially toxic elements (PTEs) constitute a class of elements composed of metals, semimetals and a non-metal. Contamination of water resources by PTEs is one of the main concerns regarding water quality and its multiple uses, due to its toxicity, persistence in the environment and potential for bioaccumulation and biomagnification at high concentrations. The Ipanema National Forest, located in the the state of São Paulo, is a Sustainable Use Conservation Unit where there was intense modification and reduction of vegetation cover, with changes in water courses and intensive use of the soil. Therefore, the present study aimed to analyze the potentially toxic elements in aquatic environments of the Ipanema National Forest. The Systematic Literature Review, presented in Chapter 1, was carried out with the objective of identifying the sources, natural and anthropogenic, of PTEs for the aquatic environment, highlighting important sources of elements of great environmental concern worldwide and highlighting the importance of attention immediate response from the government to these sources of contamination. In Chapter 2, the environmental characterization of the study area was carried out to support and understand the concentrations found and the analysis of potentially toxic elements and physicochemical parameters in the waters of the Ipanema river and Ferro brook. Total metals (TM) and dissolved metals (DM) in the water samples were analyzed. In general, when they presented significant differences, the contents of total metals were higher than those of dissolved metals, as expected, in view of the release of metals previously bound to organic matter in the quantification of total contents. However, for most elements, there were no differences between total and dissolved metals, since the samples were clear, indicating a low content of organic matter, which may have greater or lesser affinity with the analyzed elements. Aluminum, barium, iron and manganese showed differences in terms of spatial distribution. Aluminum, iron, manganese and lead presented values above the established in the legislation among all points and treatments analyzed. The quantified values did not indicate a relationship with anthropic sources, being mainly associated with the decomposition of organic matter, low water fluidity, rock and sediment composition, soil erosion on the banks, pH and redox potential.