Fluoride Action Network


Objective: To understand the relationship of dental fluorosis and IQ among children in a high fluoride area and further study the harm of high fluoride to the human body.

Method: High fluoride areas (from drinking water) in Qi County were selected as the site of investigation. The subjects of the study were 7-to-10-year-old children. Dental fluorosis was diagnosed using the Dean Index, and IQ was determined with the Chinese combined Raven’s test.

Results: The average IQ among the children in the high fluoride area was 98.06 and the rate of mental retardation was 5.47%. Intelligence distribution in the children with and without dental fluorosis did not show any difference, and no sex-specific differences in intelligence were found.

Conclusions: The long-term consumption of high fluoride water may adversely affect children’s intelligence.