Quality of drinking water fluoridation of Cap？o Bonito, SP, Brazil, evaluated by operational and external controls

purpose: to evaluate the quality of drinking water fluoridation of cap？o bonito, sp, brazil, whose optimal fluoride concentration should be between 0.6 to 0.8 ppm f, considering the balance benefits/risks. methods: historical records (n=1,964) from 2005 to 2009 of the water treatment plant (operational control) were evaluated. also, from july 2009 to june 2010, 120 samples of the network water were collected for analysis and the fluoride concentrations found (external control) were compared with records of operational control of the same period. results: according to the historical records, 76.3% of the samples had acceptable fluoride concentration and this value was confirmed by the external control done during one year, which found that 80.8% of samples were within the optimal range. however, considering the samples out the optimal range, while the records of the operational control showed values below the minimum, the results of the external control found higher percentage of samples above the maximum. conclusion: the data show the relevance to have a quality control of drinking water fluoridation because at same time the operational control analysis suggests that certain percentage of the population would not be receiving anticaries benefits, the external control indicates that it would be in increased risk of fluorosis.