Evaluation of the applicability of aquatic pollution indices: A case study in Paraibuna River (Juiz de Fora, MG, Brazil)

Abstract

Surface water contaminated by metals can configure serious risk to public health and the environment. The uncontrolled release of various pollutants in the aquatic environment is currently a priority issue for the preservation of drinking water sources in many countries around the world, including Brazil. The city of Juiz de Fora has a long industrial tradition, with emphasis on the existence of a metal and leather that dump waste without adequate treatment in the streams and rivers. A comparative assessment of different parameters in isolation provides only a limited idea of pollution with reference to that particular parameter. Therefore, in recent years has been growing interest in the use of pollution indices that incorporate the influence of different parameters simultaneously. The objective of this study was to evaluate the current status of pollution in surface waters of industrial stretch of the Paraibuna River, the city of Juiz de Fora (MG) and determine the applicability and limitations of two indices of water pollution as well documented. In this study, the results were statistically treated and showed that concentrations of Ca, Cd, Cu, Mn, Na and Zn by far exceeding the maximum permissible for some sample points making them unusable for human consumption and maintenance of an adequate environmental quality. Although the two pollution indices were statistically equal to use of the provided conflicting interpretations about the degree of pollution of surface water in these samples.