The fluoride concentration of the public water supply in the urban zone and indigenous villages of Baía da Traição, Paraíba, Brazil

Abstract

It is known that the municipality of Baía da Traição possessed a system of fluoridation of water supply. The objective of this study was to evaluate the fluoride concentration (F^-) in public water supply in the city of Baía da Traição-PB. Samples of public water supply were collected in 13 sites, one in the urban zone (downtown) and 12 in the rural zone (indigenous villages). For each site, three distinct collection points were selected for convenience between November 2015 and January 2016. The analysis was performed in duplicate, using a fluoride ion-specific electrode coupled to a potentiometer, previously calibrated. The samples (750 ?L) were added to 750 ?L of TISAB II solution, considered on a calibration curve with concentrations of 0.2 to 1 mg/L. In November, December and January, respectively, concentrations of F^- in the downtown were 0.32, 0.11 and 0.09 mg/L, and the average of the indigenous villages were 0.08 (± 0.02), 0.08 (± 0.03) and 0.07 (± 0.02) mg/L. All samples had concentrations below the recommended level (<0.60 mg/L) by the Ministry of Health for the anticaries benefit. Therefore, the public supply waters of Baía da Traição presented concentrations of F^- insufficient to prevent dental caries at the population level.