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OPINION - Study Quantifies Fluorides Potential to Reduce IQ in Children

By Dawna Gallagher-Stroeh

The first U.S. Government-funded study investigating prenatal neurological damage from fluoride, Prenatal Fluoride Exposure and Cognitive Outcomes in Children at 4 and 6–12 Years of Age in Mexico, finds that 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.* The new study is unique in approach, size, and duration, but it joins over 300 other studies finding evidence of fluoride-based cognitive damage affecting IQ. The full peer-reviewed study was published in the journal Environmental Health Perspectives (9/19/2017), and can be downloaded at the U. S. National Institutes of Health (NIH) website: Dr. Howard Hu, Dean of the University of Toronto School of Public Health, headed a team of scientists from University of Toronto, University of Michigan, McGill University, and Harvard, analyzing data from 287 mother-child pairs in Mexico City. A press release from the University of Toronto School of Public Health describes the study's methodology: The research team analyzed urine samples that had been taken from mothers during pregnancy and from their children between six and 12 years of age to reconstruct personal measures of fluoride exposure for both mother and child. “This is significant because previous studies estimated exposures based on neighborhood measurements of drinking water fluoride levels, which are indirect and much less precise measures of exposure. [Previous studies] also looked at children’s exposures instead of prenatal exposures or had much smaller sample sizes of subjects to study,” said Dr. Hu . The researchers then analyzed how levels of fluoride in urine related to the children’s verbal, perceptual-performance, quantitative, memory, and motor abilities at age four and once more between the ages of six and 12. Analyses were adjusted for other factors known to impact neurodevelopment, such as gestational age at birth, birthweight, birth order, sex, maternal marital status, smoking history, age at delivery, IQ, education, socioeconomic status and lead exposure. The study found “…higher levels of maternal urinary fluoride during pregnancy (a proxy for prenatal [placental blood] fluoride exposure) that are in the range of levels of exposure in other general population samples of pregnant women as well as nonpregnant adults were associated with lower scores on tests of cognitive function in the offspring at 4 and 6–12 y old.” Read the full article: *In his review of the new study, in the Lund Report, Rick North notes: 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. The 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... North further reports: Mexico, like most nations, doesn’t fluoridate its water. The ADA’s [dismisses the study because] the women were mainly getting their fluoride from consuming fluoridated salt or varying natural levels of fluoride in the water. [ ] North explains: “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 researcher 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.” In fact, in other contexts, fluoridation proponents frequently say, “A fluoride ion is a fluoride ion.” Read the full article: *When asked by a student, “Why are people not being seriously poisoned by drinking fluoridated water?” fluoride researcher Dr. Richard Sauerheber (B.A. Biology, Ph.D. Chemistry) replied, “Very few if any fluoridation promoters understand that fluoride at any level in the blood exerts toxic effects to varying degree in man and animals. At 3-4 ppm, as happened with citizens in Hooper Bay, AK during an accidental overfeed, this level is lethal (one victim perished from fluoride-induced heart block). At 1 ppm in the blood, as occurred in kidney dialysis wards where blood levels matched the level in the feed water, patient morbidity escalated (perishing from heart failure by a different mechanism over months of time). These events led to an FDA warning that fluoridated water cannot be used in kidney dialysis. At lower levels, around 0.1 ppm as occurs in people consuming fluoridated water, the chronic toxic effects are incorporation of fluoride into bone permanently, causing formation of bone of poor quality, and in some people hypothyroidism, and effects on the brain with IQ lowering and possible ADHD increases. Of course adverse effects on teeth enamel, hypoplasia or dental fluorosis, continues to skyrocket in incidence in U.S. teens where blood fluoride blocks normal enamelization during teeth development in children. The FDA never approved of any fluoride intended for ingestion, and banned the sale of fluoride compounds intended for ingestion by pregnant women in the U.S...” [See Dr. Sauerheber's full Comment at ] In other words, people are already being seriously poisoned by drinking fluoridated water. In the middle range, a few IQ points might not be missed, but lowering average IQ means, at the high end, fewer gifted people solving society's problems, and more mentally deficient people that society would have to deal with and care for. To understand more, watch the Fluoride Action Network (FAN) video by chemist and toxicologist, Professor Paul Connett, PhD: At the September 2016 Sonoma County Dental Health Summit, our Public Health Officer was enthusiastic about the study, Effect of Supplementation of Fluoride on Maternal Periodontal Health, Preterm Delivery, and Perinatal Well-Being (clinical trials for the study began in 2015 and continue to the present). The Fluoride Supplementation study itself warns: The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. In-utero fluoride exposure adversely affects a child's IQ, the FDA has not approved fluoride for ingestion, and yet researchers are experimenting on pregnant women by prescribing fluoride supplements. A cavity can be fixed, but a child's brain, once damaged, cannot. Please help protect our children. Put Prenatal Fluoride Exposure and Cognitive Outcomes in the hands of obstetricians and pediatricians now.

Dawna Gallagher-Stroeh, Executive Director, Clean Water Sonoma-Marin. Contact at 707-547-7006

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