Fluoride Action Network
Wednesday, December 22, 2010
Exposure to fluoride may lower children’s intelligence says a study pre-published in Environmental Health Perspectives, a publication of the National Institute of Environmental Health Sciences (online December 17, 2010).
Fluoride is added to 70% of U.S. public drinking water supplies.
According to Paul Connett, Ph.D., director of the Fluoride Action Network, “This is the 24th study that has found this association, but this study is stronger than the rest because the authors have controlled for key confounding variables and in addition to correlating lowered IQ with levels of fluoride in the water, the authors found a correlation between lowered IQ and fluoride levels in children’s blood. This brings us closer to a cause and effect relationship between fluoride exposure and brain damage in children.”
“What is also striking is that the levels of the fluoride in the community where the lowered IQs were recorded were lower than the EPA’s so-called ‘safe’ drinking water standard for fluoride of 4 ppm and far too close for comfort to the levels used in artificial fluoridation programs (0.7 – 1.2 ppm),” says Connett.
In this study, 512 children aged 8-13 years in two Chinese villages were studied and tested – Wamaio with an average of 2.47 mg/L water fluoride (range 0.57-4.50 mg/L) and Xinhuai averaging 0.36 mg/L (range 0.18-0.76 mg/L).
The authors eliminated both lead exposure and iodine deficiency as possible causes for the lowered IQs. They also excluded any children who had a history of brain disease or head injury and none drank brick tea, known to contain high fluoride levels. Neither village is exposed to fluoride pollution from burning coal or other industrial sources.
About 28% of the children in the low-fluoride area scored as bright, normal or higher intelligence compared to only 8% in the “high” fluoride area of Wamaio.
In the high-fluoride city, 15% had scores indicating mental retardation and only 6% in the low-fluoride city.
The study authors write: “In this study we found a significant dose-response relation between fluoride level in serum and children’s IQ.”
In addition to this study, and the 23 other IQ studies, there have been over 100 animal studies linking fluoride to brain damage (all the IQ and animal brain studies are listed in Appendix 1 in The Case Against Fluoride available online at http://fluoridealert.org/caseagainstfluoride.appendices.html).
One of the earliest animal studies of fluoride’s impact on the brain was published in the U.S. This study by Mullenix et. al (1995) led to the firing of the lead author by the Forsyth Dental Center. “This sent a clear message to other researchers in the U.S. that it was not good for their careers to look into the health effects of fluoride – particularly on the brain,” says Connett.
Connett adds, “The result is that while the issue of fluoride’s impact on IQ is being aggressively pursued around the world, practically no work has been done in the U.S. or other fluoridating countries to repeat their findings. Sadly, health agencies in fluoridated countries seem to be more intent on protecting the fluoridation program than protecting children’s brains.”
When the National Research Council of the National Academies reviewed this topic in their 507-page report “Fluoride in Drinking Water: A Review of EPA’s Standards” published in 2006, only 5 of the 24 IQ studies were available in English. Even so the panel found the link between fluoride exposure and lowered IQ both consistent and “plausible.”
According to Tara Blank, Ph.D., the Science and Health Officer for the Fluoride Action Network, “This should be the study that finally ends water fluoridation. Millions of American children are being exposed unnecessarily to this neurotoxin on a daily basis. Who in their right minds would risk lowering their child’s intelligence in order to reduce a small amount of tooth decay, for which the evidence is very weak.” (see The Case Against Fluoride, Chelsea Green, October 2010)
This just in from Dr. Paul Connett (The Case Against Fluoride) and the Fluoride Action Network: A very important study, titled Serum Fluoride Level and Children’s Intelligence Quotient in Two Villages in China, was pre-published by Environmental Health Perspectives (EHP) on Dec 17, 2010 (EHP is published by the U.S. National Institute of Environmental Health Sciences).
In this study, Xiang and co-workers from China found an inverse correlation between the level of fluoride in children’s blood and their IQ. Specifically, Xiang et al. show that in a village in an area endemic for fluorosis that the higher the fluoride in the children’s blood the lower the IQ of the children studied. In addition, the level of the fluoride in the children’s blood was strongly correlated with the level of the naturally occurring fluoride in their water. Please note, that the levels of the fluoride in the water in the village studied (Wamiao, Jiangsu Province, China) were not that high 2.47 +/- 0.79 ppm (range 0.57-4.50). These levels are actually lower than the EPA’s so-called safe drinking water standard for fluoride (4 ppm). Previously Xiang had reported that a linear regression analysis of their data indicated that IQ would occur at levels as low as 1.9 ppm fluoride in the water (Xiang, 2003a,b). For a study that involved about 200 children this does not leave anything like an adequate margin of safety to protect the millions of children drinking artificially fluoridated water at 1 ppm. Finding a correlation between fluoride in the blood and lowered IQ further strengthens Xiang’s earlier findings.
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Moreover, this study does not come out of the blue. It is the 24th study that has found an association between fluoride in water and lowered IQ in children. Most of these have come from China, but they also include studies published in Mexico, India and Iran. There have also been over 100 studies that fluoride can damage animal brain and studies showing that the fetal brain has been damaged in aborted fetuses in areas of China endemic for fluorosis. A complete listing of these studies can be found in Appendix 1 of the book “The Case Against Fluoride…” which is available online, with permission from the publisher.
One of the earliest animal studies of fluoride’s impact on the brain in the U.S. was by Mullenix et al. (1995). This led to the firing of the lead author by the Forsyth Dental Center (the details of this are in Chris Bryson’s book The Fluoride Deception). This treatment sent out a clear message to other researchers in the U.S. that it was not good for their careers to look into the health effects of fluoride – particularly on the brain!
When the National Research Council reviewed this topic in their 507-page report “Fluoride in Drinking Water: A Review of EPA’s Standards” published in 2006, only 5 of the IQ studies were available in English. Even so the panel found the link between fluoride exposure and lowered IQ both consistent and “plausible.” There have now been another 19 studies that have since been published or become available via English translation.
Risk-benefit analysis. Let’s put two studies in the weighing pans of a risk-benefit analysis. In the left hand pan let’s put the largest US study purporting to demonstrate fluoridation’s benefit (Brunelle and Carlos,1990) and in the right hand pan let’s put this study by Xiang, and see where the balance of wise policy lies.
The left hand pan. The Brunelle and Carlos study indicates that comparing tooth decay between children who had lived all their lives in a fluoridated community (versus a non-fluoridated one) had an average saving (for 5-17 year olds) of 0.6 of one permanent tooth surface out of over 100 tooth surfaces in a child’s mouth. Not only was this miniscule saving not shown to be statistically significant but it completely disappears if a one-year delay occurs in the eruption of the teeth of the children in the fluoridated communities (for which there is some evidence).
The right hand pan. The Xiang study (2003 a,b) indicates that their might be a lowering of IQ at 1.9 ppm, allowing an inadequate margin of safety to protect all children drinking uncontrolled amounts of water at 1 ppm (and getting fluoride from other sources). Now Xiang et al’s (2010) study strengthens this original finding by relating lowered IQ to plasma fluoride levels, which brings the finding closer to individual exposure.
Could either a parent or a decision maker possibly justify a practice that may possibly lower tooth decay by a very small amount, while it may possibly be risking their mental development? Surely the right hand scale pan must tip the left in this analysis?
This article was posted: Wednesday, December 22, 2010 at 9:02 am