Análise de parâmetros microbiológicos e de contaminação por cianotoxinas de água bruta e tratada com a finalidade de avaliação de risco à saúde pública no município de Mazagão-AP

Abstract

Brazil is the country that has the largest reserve of fresh water in the world, being the Amazon, the region that holds the largest river basin on the planet. Despite the water richness, the availability of drinking water is scarce, presenting indicators of water contamination due to the lack of sanitation and treated water for the populations, especially those that occupy the riverside areas. The study was conducted in twentyone collection points, selected as: educational institution, health institution, supply, domicile and river water in four locations in the state of Amapá. To evaluate water quality, indicators were analyzed using a qualitative and quantitative method for the presence of total coliforms, Escherichia coli, cyanophyte quantification and qualification, as well as the presence of cyanotoxins in water. The physicochemical parameters were also performed as turbidity, pH, iron, ammonia and total hardness. All results of the analyzes were compared to the maximum permitted values as provided for by the legislation in force based on Consolidation Ordinance No. 5, Anexx XX of September 28, 2017 and CONAMA No. 357 of March 17, 2005 of the Ministry of Health. The results indicated that the turbidity index and the amount of iron in the raw water were above the allowed standards. The pH for treated water was acidic and in disagreement with the legislation in 8/17 (47.06 %) samples. Total coliforms and E. coli were present in 74.07% of the samples, presenting contamination results, and a relationship between the samples were observed, since the ones with higher indices did not obtain any water treatment, from a dug well or had a deficient treatment of raw water. No indicators of cyanotoxins were detected, and we detected only one cyanobacterium species in a single sample. However, other phytoplankton classes and genera were quantified and qualified, demonstrating the Amazonian aquatic biodiversity. Given the above, this research aimed to evaluate the hygienic-sanitary quality of raw water and consumption through microbiological indicators and cyanobacteria and cyanotoxins as potability parameters in the municipalities of Mazagão, Porto Grande, and Santana.