Determinação de Metais Poluentes em Cursos de Água e Peixes do Alto da Bacia do Rio Paranaíba em Goiás

Abstract

The southern Goiás has stood out for being one of the largest dairy basins of the state of Goias in recent years spurred the increase in the number of agricultural industries. The dairy farming in this region is predominantly extensive and has been identified as sources of pollution of streams in the region. The study aimed to evaluate the presence of metal pollutants in fish and water from streams Paranaíba River Basin, Goiás, considering four municipalities: Goiatuba (A), Itumbiara (B), Morrinhos (C) and Piracanjuba (D). We collected water samples and fish in thirty points in the period from July to September 2009 in which we determine the concentrations of Cu, Fe, Mn, Zn, Cd, Pb, Cr and Al by atomic absorption spectrometry. Fish in the presence of Al, Fe, Mn, Zn, Cd, Pb, Cr and Cu were detected above the limits determined in 27.2% of the samples ANVISA/1998. The highest values found in the water Zn = 2.15, 1.95, 5.43 and 5.83 mg/mL-1, Mn = 0.26, 0.50, 0.42 and 0.50 mgmL-1 and Al = 1.94, 0.98, 1.97 and 2.80 mg/mL-1, Fe = 0.05, 0.15, 0.09 and 0.15 for A, B, C and D respectively . The concentrations of Cu, Cd, Cr and Pb are given below the detection limit. The points show up 5.00 mg/mL-1 Zn and Al ≥ 0.20 mg/mL-1 are above the standards established by CONAMA. It is concluded that the contamination of fish in the municipalities comes from the sediment, as these metals were not detected in the water. In water samples taken tested with variability at a 5% level of significance showing no difference in the values found upstream and downstream of the reference point.