Assessment of the quality of water for consumption by river-bank communities in areas exposed to urban and industrial pollutants in the municipalities of Abaetetuba and Barcarena in the state of Pará, Brazil.

In spite of the great technological advances in processes for treatment of water for human consumption, water actually used for supply has become a major public health challenge. This study assesses the quality of the water consumed in two riverside communities in the Brazilian state of Pará, in an area exposed to domestic and industrial pollutants. Four campaigns of sampling were carried out in the two communities. The variables used for the calculation of the water quality index - Índice de Qualidade da Água, or IQA - were: pH, total solids, chloride, fluoride, hardness and N-Nitrate. The waters used for human consumption in the Maranhão Community, where there is no contamination by industrial pollutants, presented adequate samples, with improvement in the dry season; on the other hand the waters of the Vila do Conde, a location close to the industrial activity, had quality that was unacceptable for human consumption in both the seasonal periods. The principal parameters affected were pH and N-Nitrate, with values up to 25 times the reference level of the Brazilian legislation for water for human consumption. These results indicated greater anthropic interference in the vicinity of Vila do Conde, in Barcarena. It is concluded that this population is in need of clinical assessments by specialized professionals on the state of its health.