Mining causes numerous environmental impacts; among them we have to mention the water contamination due to the residues inherent to the activity. "Morro do Níquel", a mining site, located in southwest Minas Gerais, Brazil, has promoted an increase in the mining activity in the region. There has also been an increase in the amount of residues and substrates produced with the intensification of the mining activity. Being a purification derivative and the extracted minerals processing, the heavy metals have been accumulating in the ecosystem, being able to interfere with the population's quality of life and health in the municipality of Pratápolis. Heavy metals are a class of highly reactive and some toxic substances. Such toxicity is caused by the inability of the organism to metabolize them, leading to bioaccumulation. Therefore, the present research aims to determine the presence of heavy metals in the surface water, supplying water and irrigation water in the city of Pratápolis-MG, in addition to evaluating the water quality through physical and chemical analyzes.

Large amounts of effluents, some even untreated, used in the dyeing industries are dumped into natural water provoking a huge environmental impact daily. The Analytical Chemistry and Polymer Technology Group from the University of Sao Paulo in Sao Carlos, Brazil developed the polyurethane foam. It is a unique type of foam produced from vegetable oil-a renewable natural raw material. The objective of the research was to verify the effectiveness of adsorption of textile dyes in effluents through the polyurethane foam derived from vegetable oil. The dye samples collected from an industry in the dying segment in the city of Passos, Minas Gerais State, Brazil, were prepared in various predetermined concentrations. The percolation in thermostatic glass column containing polyurethane foam derived from vegetable oil was used as analytical method, with known mass, pressed in the form of powder between two solid foam disks containing two millimeters of thickness.