Urinary Fluoride Excretion by Preschool Children from a Rural-Community

Urinary fluoride excretion has been used as biomarker of fluoride exposure to derive data relating to its safety and its efficacy in caries prevention. In Mexico, children are consuming fluoridated salt with every meal and the excretion of fluoride has been associated with the amount of fluoride intake, but there are few studies from rural communities that consider the nutritional status.

Objective: The purpose of this study was determined the total daily fluoride excreted through the urine and to assess the caries prevalence of children aged 3-5 years with malnutrition.

Method: Urinary multiple samples from 24 hours were collected from 50 preschool children living in a rural community with fluoride concentration of 0.3 mg/L in the drinking water and consuming domestic fluoridated salt. Children were divided into two different groups according malnutrition status. Caries decay was scored by one clinical examiner previously calibrated in dmf-t index (Kappa= 0.89). The determination of the amount fluoride excreted was made using a specific fluoride ion electrode (model 720-A Orion research). ANOVA test was used to compare the groups.

Results: The childrenxs average urinary fluoride concentration was 0.76± 0.45 mg/L. The mean of 24 hours total fluoride excreted was 292±110 µg/24 hrs. The 88% of the children presented caries decay, the mean of dmf-t was 5.3±3. There were no statistically significant differences between groups.

Conclusion: The urinary fluoride excretion was lower than those values indicated by the World Health Organization for populations with optimal fluoridation. Caries prevalence and severity were high, so it was concluded that these children are receiving suboptimal amounts of fluoride for the prevention of caries decay.

PAPIIT 208/807

Key words: fluoride excretion; malnutrition, caries, rural preschool children