Fingernails as a biomarker for dental fluorosis

Introduction: Biomarkers indicate levels of a particular chemical agent in the environment studied, which may be useful for monitoring health status, and nails may be major indicators of fluoride. Objective: To evaluate fluoride concentration in the fingernails of children as a biomarker for fluoride exposure. Methods: Twenty students were selected, aged 4-5 years old. Their nails were cut at 15 and 45 days (two collections), and the fluoride concentration in the nails was analyzed with the ion-specific electrode (Orion 9409) after rapid diffusion with HDMS. Results: The total fluoride mean of the samples was 3.68 μg F/g (sd 1.44), ranging from 1.39 μg F/g to 7.81 μg F/g. Eleven children (55%) brush their teeth three times a day, but only three children (15%) swallow toothpaste. Conclusion: There is a high prevalence of fluoride exposure in the fingernails of the children studied, presenting risk of developing dental fluorosis in permanent teeth.