IMPACTOS PROVOCADOS POR METAIS POTENCIALMENTE TÓXICOS DISSOLVIDOS EM ÁGUA E EM SEDIMENTOS NO CÓRREGO DO CINTRA -- BOTUCATU-SP.

The objective of the present study was to investigate the impact of metals dissolved and in sediments in the Cintra Stream located in Botucatu city, SP, downstream Unesp Campus SP, Brazil. The potentially toxic metal dissolved in the water were detected in most of the collection places. Points 1 to 7 surpassed the maximum index allowed by Resolution of CONAMA no 357/2005, for the Cd (until 0,280 mg. L-1), Fe (5,0 to 47,79 mg. L-1), Ni (0,027 to 0,378 mg. L-1), Zn (< 5,0 mg. L-1), Pb (0,033 to 0,072 mg. L-1), Cu (0,028 to 3,82 mg. L-1). It was also detected the possible focal generating sources (effluent treated and not treated) and diffuse (agrochemistry and lixiviated residues of the "Marechal Rondon" high-way) that significantly impairs the water quality. As for the physical and chemical parameters studied, only the electrical conductivity-EC presented indicative values of pollution in almost all the sites (over 100mS/cm). Metals in sediments presented high values, which probably are impairing the aquatic biota. Corrective mechanisms in the main generate focus of pollution, continued education to the agriculturists who use agrochemistry and mitigate measures in the reduction of "rainfall-runoff" from the road, are necessary measures for the recover water quality along Cintra stream, for the use and occupation of the ground or for recreation purposes. [ABSTRACT FROM AUTHOR]