In the summer of 2008, the following two reports reviewed the published studies reporting an association of high fluoride exposure and reduced IQ. The fluoride levels in water in these studies range from 0.88 – 9.4 ppm.

Connett M, Limeback H.
Fluoride and its effect on human intelligence. A systematic review.
International Association for Dental Research 83rd General Session and Exhibition. Toronto, Canada.
Poster 2205. July 4, 2008.

Tang Q-Q, Du J, Ma H-H, Jiang S-J, Zhou X-J.
Fluoride and Children’s Intelligence: A Meta-analysis.
Biol Trace Elem Res. 2008 Aug 10. 2008.

The Tang et al. study cites 16 studies, including 5 Chinese studies that had not been translated into English. FAN plans to have them translated.

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