The Effects of High Levels of Fluoride and Iodine on Child Intellectual Ability and the Metabolism of Fluoride and Iodine

The authors carried out a study on the intellectual abilities and fluoride/ iodine metabolism of children living in a high fluoride-high iodine area. Among the results: the percentage of the general population living in this fluoride/iodinecontaminated region that suffered from goiter (clinical thyroid enlargement) was 3.8%, the rate of children already showing some thyroid enlargement was 29.80%. Similarly, the rate of dental fluorosis for the general population was 35.48%, while for children it was 72.98%. Student subjects had average IQs of 76.67±7.75, with 16.67% of the IQs in the “low” category. The iodine content and fluoride content of the children’s urine were 816.25±1.80 μg/L and 2.08±1.08 mg/L, respectively, significantly higher than the control. The thyroid glands of the subjects showed a markedly lower uptake rate of iodine-131 when compared with the control, the values after 3 hr and 24 hr were 9.36±1.55% and 9.26±4.63%, respectively, and the blood serum levels of thyroid stimulating hormone (TSH) were significantly higher than the control. The results indicate that high levels of fluoride and iodine have a serious damaging effect on the body, and should be given greater attention.