Fluoride concentration in public water supply: 72 months of analysis

Abstract

Known as one of the ten most important advances on Public Health in the 20th century, fluoridation of public water supply is a measure of wide population coverage, which is effective on caries control. The city of Araçatuba, in the Northwest region of the São Paulo state, Brazil, started public water supply fluoridation in 1972 and, based on the average annual highest temperature, has kept the fluoride concentration between 0.6 to 0.8 mgF/L. The purpose of this study was to analyze monthly the fluoride concentration in public water supply in the city of Araçatuba during 72 months. Water samples were collected monthly on weekdays, directly from the water distribution network, on pre-established locations and analyzed in duplicate between November 2004 and October 2010 at the Research Laboratory of the Nucleus for Public Health (NEPESCO) of the Public Health Graduate Program from Araçatuba Dental School/UNESP, Brazil, using an fluoride-specific electrode connected to an ion analyzer. From the total of samples (n=591), 67.2% (n=397) presented fluoride concentration between 0.6 and 0.8 mgF/L; 20.6% (n=122) below 0.6 mgF/L; 11.5% (n=68) between 0.8 and 1.2 mgF/L and 0.7% (n=4) above 1.2 mgF/L. Most samples showed fluoride levels within the recommended parameters. Minimal variation was observed among the analyzed collection locations, showing that the city has been able to control the fluoride levels in the public water supply and reinforcing the importance of surveillance and constant monitoring to assure the quality of the water delivered to the population.

Clinical aspects of dental fluorosis according to histological features: a Thylstrup Fejerskov Index review

“…Water fluoridation is effective method preventing tooth decay when used at optimal concentration, according to the local average temperature (26). The temperature factor directly affects the amount of water intake, increasing the fluid intake, especially in tropical areas (27).…”

Dental fluorosis and its influence on children’s life

“…Water fluoridation is an effective and safe means of preventing dental caries; therefore, monitoring of the quality of the public water supply and its fluoride levels is necessary and should be a priority in health vigilance activities. 25,26,27 The results of this study will assist municipal health services by demonstrating that a 1.2 ppm fluoride concentration does not greatly affect the population and, therefore, there is no need for costly investments in the adequacy of the water supply system.…”

Vigilância da concentração de flúor nas águas de abastecimento público na cidade de Passo Fundo - RS

“…Ao contrário destes achados, alguns estudos demonstram concentrações ideais de flúor para a redução da cárie dentária nas águas avaliadas. Estudo realizado em Araçatuba, no Estado de São Paulo, cidade com data de mesmo início de fluoretação da cidade de Passo Fundo (1972), foram avaliados os teores de flúor durante 72 meses e os resultados apresentaram que 67,2% das amostras de água estavam com níveis de concentração aceitáveis (entre 0,6 a 0,8 mg/L de F) 22 . Segundo estudo realizado em Bauru, no Estado de São Paulo, nas 737 amostras de água coletadas em 19 setores de abastecimento, a concentração média de flúor variou de 0,37 a 1mg/L.…”