Fluoride Action Network


Children, aged 9–10½, from 22 villages in Jing County, Hubei Province, China, with different levels of fluoride in the drinking water were tested for their IQs according to the revised version of Raven’s Standard Progressive Matrices. Among 141 children in villages with 2.1–4.0 ppm F in the drinking water, 34 (24.11%) had IQ scores in the top three categories (1–3) of intelligence; among 147 children in the villages with 0.1–0.2 ppm F, the number was 40 (27.21%), and among 159 children in villages with a “normal” 0.5–1.0 ppm F, the number was 92 (57.86%). For the lowest two IQ categories (4 and 5), the percentages were, respectively, 75.89, 72.79, and 42.14%. The reasons for this non-monotonic pattern are not clear.

Translated by Julian Brooke for the Fluoride Action Network and published with the concurrence of the Chinese Journal of Control of Endemic Diseases 1990;5(4):203-4 in the journal Fluoride.