Groundwater quality in the Uberaba-MG urban area: health risk assessment

Abstract

Despite its importance from the social and economic point of view, and being more protected than surface waters, groundwater can be contaminated by several sources, compromising its quality for supply and requiring high financial and human resources investment for its remediation. The objective of the present study was to analyze the quality of groundwater in 8 wells distributed in neighborhoods of the city of Uberaba-MG and to evaluate the health risk based on the concentration of potentially toxic metals and nitrate ions. The parameters analyzed in the dry and rainy seasons were microbiological (total and thermotolerant coliforms), physical (conductivity, temperature, turbidity and color) and chemical (pH, potentially toxic metals, alkalinity, chemical oxygen demand, total phosphorus, nitrate, chloride and hardness). All the wells analyzed presented total and thermotolerant coliforms in at least one station. When compared to the legislation in force, the parameters color, COD, total phosphorus, iron, cadmium, lead, nickel, manganese and chromium presented values above the allowed limits, especially in the dry season. The health risk analysis was significant for four wells studied, being cadmium the parameter with the highest risk coefficients, followed by chromium. These changes need to be constantly monitored in order to know the real quality of groundwater for consumption. Thus, the results found contribute to the design of future studies, serving as a subsidy for environmental and public health managers.