Banca de DEFESA: RONISON SANTOS DA CRUZ

Environmental perception of chemical risk and occurrence of toxic metals in Iripixi Lake, Oriximiná-PA

environmental perception, toxic metals, urban lake

One of the central aspects of the discussion of natural resource pollution stems from the increasing exposure of natural and human environments to nonpolar chemical compounds such as toxic metals and pesticides. In the municipality of Oriximiná- PA due to urban expansion and agricultural activities on the shores of Lake Iripixi, ecotoxicological studies can be used as instruments to defend environmental and human health. The objective of this work was to evaluate the environmental perception of the residents around Lake Iripixi regarding pesticide exposure and toxic metal occurrences in relation to the environment and public health. Data collection was done by applying a semi-structured questionnaire, closed and open. For the analysis of toxic metals, in this study we adopted the protocol Sediment Quality Assessment Directive (DAQS). The DAQS evaluated the degree to which the chemical status of the toxicant when associated with sediment adversely affects aquatic organisms. Multivariate analyzes of toxic metal content in sediments were performed. Pearson correlation analysis, factor analysis (FA) and hierarchical cluster analysis were also performed. According to the data, the description of the environmental problems listed by the residents around the Iripixi lake, Oriximiná-PA, were; 50% sewage; silting 26.08%; deforestation 2.17%; pesticide 4.34%; eutrophication 2.17% and another 15.21%. Lack of sanitation is the biggest environmental problem in the region where they live. Toxic metal contents Al, Cd, Cr, Cu, Ni, Pb and Zn are within the proposed reference values (VR) 1 for unpolluted surface waters and sediment in the Amazon. Important strategies must be implemented to reduce the discharge of domestic effluents; such as controlling non-point agricultural pollution to reduce the environmental risks associated with toxic metals.