RESUMEN
BACKGROUND: The preliminary study was undertaken with the aim to assess the effect of fluoride content in water on the Intelligence Quotient (IQ) of school children aged 12-13 years residing in areas that differ with respect to fluoride levels. MATERIALS AND METHODS: The IQ was measured using Raven's Colored Progressive Matrices in 90 children, who were life-long residents in three villages (30 children each) of similar population size but differing in the level of fluoride in drinking water. Urinary fluoride concentration was measured using the selective ion electrode technique. One-way ANOVA was used for the statistical analysis of the data. Results: Children who lived in locations with fluoride levels of 1.60, 6.70, or 2.80 parts per million in their drinking water had urinary fluoride concentrations of 1.60, 6.82, or 2.69 parts per million, and IQ scores of 16.77 + 8.24, 19.36 + 9.98, or 21.87 + 7.47, respectively. CONCLUSION: The results indicated that there was a positive correlation between excess fluoride in drinking water and IQ.