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IQ Losses Continue to Haunt Fluoride

October 4, 2017

On September 19, Environmental Health Perspectives, a highly-respected journal, published a study linking higher fluoride levels in pregnant women to lower IQ’s in their children.

The decrease was significant. Each 0.5 part per million (ppm) increase in a pregnant woman’s urine fluoride levels reduced her child’s IQ by 2.5 - 3 points. A child of a mother drinking 1 ppm of fluoridated water, close to the U.S standard of 0.7 ppm, would be expected to have a drop of 5 to 6 IQ points compared to a child of a mother drinking water with close to no fluoride in it.

This prospective study was funded by the U.S. National Institutes of Health and led by researchers at the University of Toronto School of Public Health.

It was very strong, following pregnant women in Mexico and their children for 12 years, and measuring individual urine levels, a more precise method to determine fluoride exposure than drinking water concentrations. The results were undiminished even after adjusting for a wide array of confounding factors, including lead, smoking, alcohol, socio-economic status and birth weight.

The pro-fluoridation lobby, led by the American Dental Association, quickly denied the significance of the study, arguing “the findings are not applicable to the U.S.”

Mexico, like most nations, doesn’t fluoridate its water. The ADA’s stance stems from the fact that the women were mainly getting their fluoride from consuming fluoridated salt or varying natural levels of fluoride in the water. (The ADA ignores the fact that fluoride’s effects are the same once it’s inside the body, no matter the source.)

Most others felt differently. Lead author Dr. Howard Hu asserted “This is a very rigorous epidemiology study. You just can’t deny it. It’s directly related to whether fluoride is a risk for the neurodevelopment of children. So, to say it has no relevance to the folks in the U.S. seems disingenuous.”

Dr. Leonardo Trasande, a pediatrician unaffiliated with the study at New York University, agreed, saying that “This is a very well-conducted study, and it raises serious concerns about fluoride supplementation in water.”

And according to CNN, Dr. Linda Birnbaum, director of the National Institute of Environmental Health Sciences, “pointed out that it raised significant questions.”

Although this study is new, it has long been recognized that fluoride causes brain damage. The extent of harm is based on the dose, when and how often the exposure occurs, and which individuals are at greater risk.

In 2006, the National Academy of Science’s National Research Committee (NRC) published Fluoride in Drinking Water, a review of over 1,000 studies. It’s considered the most well-balanced, comprehensive, authoritative study ever done on fluoride’s toxicity. The 12-member scientific committee leading the effort, including three who favored fluoridation, stated unequivocally that “It is apparent that fluorides have the ability to interfere with the functions of the brain and the body by direct and indirect means.” (p. 222)

In 2012, a Harvard-funded meta-analysis found that children in China exposed to higher levels of fluoride tested lower for IQ in 26 out of 27 studies. The average difference was significant - 7 IQ points lower. The quality of the studies varied and dealt with higher exposures of fluoride than in the U.S. However, several were methodologically strong, controlling for potential confounders such as lead and arsenic, and had doses close to those typically found here.

In 2014, in the British medical journal The Lancet, two world-renowned scientists, Philippe Grandjean, MD and Philip Landrigan, MD, added fluoride to the list of 11 chemicals identified as developmental neurotoxins – harming the brains of children. Grandjean, a co-author of the 2012 Harvard study, commented at the time that “Fluoride seems to fit in with lead, mercury and other poisons . . .

Last year, the Fluoride Action Network, American Academy of Environmental Medicine, International Academy of Oral Medicine and Toxicology, Food and Water Watch, Organic Consumers Association and several others, including individual mothers, petitioned the EPA to ban fluoridation chemicals based on their neurotoxicity.

The petition cited 196 peer-reviewed studies – human, animal, cellular and reviews - published over the last ten years. Virtually all the studies - 189 - found harm, such as lowering IQ or increasing behavioral problems, several at levels consumed by Americans, and more at minimally higher levels.

The studies with slightly higher levels are quite relevant to common exposures in the U.S. Genetics, environmental and socio-economic factors cause significant variability among humans in their resistance to disease. It’s standard toxicological practice to divide the lowest level of harm detected by at least 10. Many studies show there is typically at least a 10-fold variation in sensitivity to any toxin among humans.

The NRC 2006 review determined that water fluoride levels of 4.0 ppm are definitely harmful to human health, so dividing by 10 wouldn’t allow more than 0.4 ppm. Yet the CDC recommends 0.7 ppm, nearly double the level, ignoring this established scientific practice.

In February, the EPA denied the petition, saying there wasn’t conclusive data that fluoride was neurotoxic, in spite of the massive evidence to the contrary. The organizations have sued the agency and the case is now in federal court.

Hu and his fellow authors don’t say, nor do I, that this one study provides conclusive proof that fluoridating water lowers IQ’s in children. But there’s no denying 30 years of hundreds of studies pointing squarely in that direction and the U. of Toronto results add even more credibility.

Moreover, there are very few studies finding that fluoride doesn’t lower IQ. The New Zealand study most often cited used an unsuitable study group with little contrast in total fluoride exposure. Many kids with unfluoridated water were ingesting fluoride tablets, making their total consumption of fluoride nearly as high as the kids drinking fluoridated water.

Fluoridation proponents believe the burden of proof is to show conclusively that a substance is harmful before it’s disallowed.

We’ve seen this misguided thinking before. In 1954, responding to numerous studies showing correlations between smoking and lung cancer, the tobacco industry asserted “there is no proof that cigarette smoking is one of the causes.” As late as 1994, industry executives

again declared at a Congressional hearing that correlation wasn’t enough and smoking hadn’t been proven to be a cause of cancer.

The opposite point of view – “First do no harm” or “Better safe than sorry” – reasons that a substance should be demonstrated safe before it’s allowed. Obviously, this hasn’t happened with water fluoridation. The NRC, identified numerous other links to fluoride, including thyroid disease (p. 8), kidney disease (p. 303) and diabetes (p. 260), calling for further research.

Fluoride is now a known neurotoxin. If you put it in water, how do you control the amount people consume, the age at which they consume it and the harm to those at highest risk – born or unborn? You can’t.

The amount of this poison you ingest is determined, incredibly, by how thirsty you are. If you’ve concluded this practice is exceedingly unwise, you’re not alone. The vast majority of nations, cities and health organizations worldwide don’t support fluoridation and ethical concerns loom large as to why so many European nations oppose it. In effect, everyone drinking fluoridated water is participating, without their consent, in a continuing medical experiment.

The CDC and EPA have many qualified, well-meaning people who’ve done a lot of good work. But history is rife with examples of the U.S. government assuring us that substances like leaded paint and gas, asbestos, DDT, DES, cigarettes, etc. were safe.

It took decades of science finding harm before the government belatedly banned or restricted them. The amount of impairment, suffering, disease and death occurring in that lag time is incalculable – and unnecessary.

It’s time to be on the right side of history.

It’s time to end water fluoridation.

Rick North is the former executive vice president of the Oregon American Cancer Society and former project director for Oregon Physicians for Social Responsibility’s Campaign for Safe Food. Now retired, he’s a volunteer advocate for safe water, safe food and the preservation of democracy. He can be reached at [email protected].