Surface water quality in rural communities in the state of Goiás during the dry season and its relationship with land use and occupation

Abstract Different land uses and occupations can influence water quality and affect the lives of the population, especially of people who live in rural areas. Because rural populations live under conditions of socio-environmental vulnerability, it is necessary to monitor the quality of water resources to prevent diseases. This work aimed to analyze surface water quality in rural and traditional communities in the state of Goiás through the Bascarán Water Quality Index (WQIB) to evaluate the effects of the predominant land use and occupation of each location. Raw water samples were collected from specific points during the dry season. The presence of pesticides was verified through chromatographic analysis, without quantification, and 11 physical-chemical and microbiological parameters were assessed according to standard methods. The results showed that the WQIB ranged in quality from “good” to “pleasant”. Classification as “pleasant” was statistically related to a high incidence of pasture area (> 80%) and classification as “good” with a percentage of agriculture below 30%. The main land uses and occupations were forest, pasture and agriculture. The apparent parameters color, thermotolerant coliforms and dissolved oxygen also indicated contamination of water courses. The detection of pesticides with a high degree of toxicity in the analyzed water resources, mainly in two rivers (the Facada and Sucuapara creeks), put human health at risk in rural areas, even under conditions of small exposure. Carbofuran, banned since 2017, was detected near the Itacaiú community, making it necessary to alert the local government, residents and tourists who use the Araguaia River for different purposes.