Fluoride Action Network

The Fluoride IQ studies

There are now 76 out of 85 IQ studies reporting lowered IQ from exposure to elevated levels of fluoride. Since 2017 we learned that the fluoride level of 0.7 mg/L, the "optimal" level used in U.S. and Canadian drinking water fluoridation projects, can create neurodevelopmental harm to the fetus, bottle-fed infant, and child. The fetus and bottle-fed infant were never considered in any risk assessment for water fluoridation by any regulatory agency in any fluoridating country.

A little history on the Brain and Fluoride

By Ellen Connett

The earliest studies on the brain were reported by Kaj Roholm in his 1937 treatise Fluorine Intoxication H. Trendley Dean, the father of fluoridation, called the treatise “the outstanding contribution to the literature of fluorine” in a 1938 review.

Roholm noted that “Free fluorine plays no part in toxicology, as it immediately reacts with water, forming hydrogen fluoride.” He reported human necropsy results that show the brain was affected (“brain hyperæmia or oedema”). He also cited Horsford who “proved the presence of fluorine in the human brain” in his 1869 study (page 58) and another study by Schultz in 1889 (reference 719), who stated that fluoride had “a particular depressive action of the brain.”

But it was the 1995 study by Mullenix et al., Neurotoxicity of sodium fluoride in rats that excited interest in fluoride’s neurotoxic effects in the U.S. It also provided a window into flawed U.S. agencies that were more interested in protecting public policy than in protecting the public’s health. Dr Mullenix lost her job after the paper was published and never worked in academia again. Read a 1997 interview with Dr Mullenix and Paul Connett at https://fluoridealert.org/content/mullenix-interview/

The studies on fluoride’s effect on the brain prompted the Fluoride Action Network to translate the earlier Chinese studies reporting on exposure to fluoride and reduced IQ in children. FAN’s translaton project includes:

1989: Research on the intellectual ability of 6-14 year old students …
1989: A study of the intellectual ability of 8-14 year-old children …
1990: …level of fluoride in drinking water on the intellectual ability..
1991: …relationship of a low-iodine and high-fluoride environment to subclinical cretinism..
1991: Using drawing tests to measure intelligence in children …
1991: … intellectual development of children in high fluoride areas.
1991: A preliminary investigation of the IQs of 7-13 year old children …
1992: The effects of high fluoride on the level of intelligence …
1994: … high levels of fluoride and iodine on intellectual ability …
1994: …excessive fluoride intake on mental work capacity of children…
1994: The effect of fluorine on the level of intelligence in children
1995: A comparative analysis of the results of multiple tests in patients with chronic industrial fluorosis
1996: …TSH and intelligence level of children with dental fluorosis..
1996: …IQ levels of 4-to 7-year-old children in high fluoride areas
1997: ….physical and mental development of children…
1998: The effect of high levels of arsenic and fluoride on the development of children’s intelligence.

The western world was unaware of the Chinese studies that associated exposure to fluoride and lowered IQ. We found these studies easily enough in PubMed’s abstracts on fluoride as the abstracts of some of the Chinese studies were in English. The regulatory agencies could have found them just as easily as we did. Particularly the Environmental Protection Agency (EPA) which is responsible for setting the regulatory-enforced Maximum Contaminant Level of fluoride in drinking water fluoridation schemes. But, EPA wasn’t reading the science, most likely because it was too controversial. They depended on outside contractors to write the few reports that they published on fluoride. Little did the public know that pregnant women, the fetus, and infants under 6 months, were never considered in any of EPA’s “health risk assessments” on adding fluoride to the drinking water of millions of Americans.

The first IQ studies in English were published in the journal Fluoride

1995: Effect of fluoride exposure on intelligence in children.
1996: Effect of high-fluoride water supply on children’s intelligence.

But the problem with these studies, and the many more published in this journal, is that few people knew about them because PubMed, the leading online provider of science and medical abstracts, refused to index the journal Fluoride. The only rational reason for this anti-scientific position is that the journal Fluoride published many articles on the toxicity of fluoride which ran counter to the U.S. public health policy of purposefully adding it to drinking water in the hope of preventing dental caries. Studies such as the journal’s 1964, “Kenetics of Fluoride Penetration in Liver and Brain,” by Geeraerts et al. were not wanted. The National Institutes of Health sponsors PubMed.

Based on an accumulating body of research, there have been several prestigious reviews — including a report authored by the U.S. National Research Council, a meta-analysis published by a team of Harvard scientists, a review published in The Lancet, and three U.S. government-funded Mother-Offspring studies that found a link between fluoride in the urine of pregnant women and lower measures of intelligence in their children (Till 2020; Green 2019; Bashash 2017).

The National Toxicology Program (2016 – present)

The NTP’s draft Systematic Reviews of fluoride’s neurotoxicity began in 2016. The first draft was released in 2019 and the revised draft was released in 2020.

Both reviews concluded “that fluoride is presumed to be a cognitive neurodevelopmental hazard to humans.”

This systematic review was inexplicably ended on February 9, 2021, after 5 years and a few million dollars spent. The public found out after EPA’s lawyers informed the Court in the TSCA trial (below). See more here.

The TSCA trial against the EPA to ban fluoridation chemicals (2016 – present)

In 2016, a Section 21 Citizens’ Petition under the Toxic Substances and Control Act (TSCA) was presented to the U.S. Environmental Protection Agency (EPA) to ban the addition of fluoridation chemicals into drinking water because of fluoride’s neurotoxicity at the levels (0.7 mg/L) used in fluoridation schemes. Food and Water Watch, Fluoride Action Network, and MOMS Against Fluoridation, were among the petitioners. EPA denied the petition and the Petitioners sued EPA. A 2-week court trial was held on zoom in June 2020. The Court has still not ruled. It is waiting on a report from the National Toxicology Program. The NTP is planning to release a “state of the science report” which will have no conclusions. It is widely believed that the NTP is under intense pressure to downplay the conclusions they twice reached

“that fluoride is presumed to be a cognitive neurodevelopmental hazard to humans”

to protect U.S. pro-fluoridation policy and the officials who promote it within U.S. agencies.


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