Fluoride Action Network


As part of a 2002-2003 investigation on the effects of high fluoride drinking water on IQ scores of children, serum fluoride (F) levels in the children were subjected to further study. Among the new findings, although IQ scores of boys and girls differed in the seven IQ level categories, there were no overall gender differences (boy/girl ratio 1.220 vs. 1.214 in the high and low F villages, respectively). However, the mean IQ was significantly higher and there were fewer children with an IQ less than 80 in the two quartiles with a serum fluoride level of less than 0.05 mg F/ L. Analysis of the overall relationship between IQ scores and serum F levels indicates there may be no serum F level below which adverse effects on IQ might not be present.