Fluoride intake by Brazilian children from two communities with fluoridated water

Objective: To determine total daily fluoride intake by young children from two communities in a developing country. Methods: Fluoride intake from diet and dentifrice was determined for 71 Brazilian children, aged 19-38 months, living in two communities with fluoridated water (0.6-0.8 ppm). The children from Piracicaba attended a full-time day care centre but those from Ibia did not. Fluoride ingested during tooth brushing was determined, and 'duplicate-plate' samples of all foods and beverages ingested during a 2-day period were collected from which fluoride for analysis was extracted by hexamethyldisiloxane (HMDS) microdiffusion. The amount of fluoride ingested (mg F/kg body weight/day) from the diet and dentifrice and the combined fluoride intake were calculated. A limit of 0.05-0.07 mg F/kg body weight/day was considered as the safe threshold for fluoride exposure. Results: The children from Ibia had lower amounts of fluoride in their diets than those from Piracicaba (P < 0.05); no differences in the amount of fluoride ingested from dentifrice were found between the communities. In both communities, the daily fluoride intake from dentifrice was higher than that from the diet (P < 0.05). Most of the children from both communities were exposed to a combined dose (diet + dentifrice) of fluoride above the risk threshold for dental fluorosis. Conclusion: The data suggest that fluoride intake from diet depends on living conditions, and measures should be implemented to reduce the fluoride intake of these Brazilian children.