Panorama of the water supply in the Campinas region and a brief comparison with other regions in the Southeast of Brazil

Abstract Access to drinking water is one of the most important factors for health. The lack of access to safe drinking water results in a high prevalence of infections, such as bacterial gastroenteritis and outbreaks of diarrhea. This study evaluated the quality of the public water supply in 42 municipalities located in the eastern region of the State of São Paulo, Brazil, from 2016 to 2020. Physical, chemical, and microbiological parameters were investigated. Sample collection, preservation and analyses were carried out in accordance with national and international standards. The results demonstrated non-compliance with Brazilian legislation for apparent color (1.1%), turbidity (0.4%), fluoride content (14.2%), total coliforms (4.4%) and Escherichia coli (E. coli) (0.4%). In a brief comparison with other studies in the southeastern region of Brazil, the highest percentage of unsatisfactory samples is due to the fact that fluorine is below the minimum of <0.6 ppm, demonstrating the need for training in the fluoridation process. The need to invest in the training of health surveillance teams to carry out field analyses (chlorine and pH) was also observed. This study can inform future actions, guiding the adoption of preventive and corrective measures and demonstrating the importance of monitoring water-supply quality.