The Journal of History     Fall 2002  TABLE OF CONTENTS
Is Fluoride Adversely Affecting
Minority Children's Intelligence and Behavior?
(Is It Affecting ALL Children and Their Parents Too?)


Author Unknown
March 23, 2001

Dartmouth Researcher Finds Increased Uptake of Lead

CANTON, NEW YORK -- The chemicals currently used to fluoridate much of the water in the US may be causing increased blood lead levels in children, results of a new study show.

Dr. Roger Masters of Dartmouth College and colleagues looked at data consisting of over 150,000 children's blood lead tests, and found levels significantly elevated in areas where chemicals known as silicofluorides (SiF), used in over 90% of the fluoridated water in the US, are used.

Controlling for other factors associated with high blood lead, the odds of children having venous blood lead over the standard cut-off of 10ug/dL were significantly higher where SiFs were in use, with the odds often doubled or tripled for minorities.

"Our findings suggest that water fluoridation -- often justified by supposed benefits to minorities -- actually has extremely NEGATIVE effects. Given the link between high blood lead and hyperactivity, learning disabilities, drug use, and aggressive behavior, many of the stereotypical racially biased beliefs about Blacks and Hispanics have apparently been reinforced by the unsuspected effects of toxic chemicals intentionally added to the water supply" asserts Masters.

The study, published in the journal "Neurotoxicology," reinforces the findings of two previous studies by the same researchers. Other data, now in press, show that controlling for other factors, SiF usage also contributes to significant increases in rates of violent crime, says Masters.

"Dumbing Down" and Behavioral Effects

"Apart from other dangerous effects, the tendency of SiF to enhance absorption of lead is of incalculable importance, because among the well-known consequences are its effects on intelligence and cognitive ability, which can be permanent and severe," according to Masters.

Even at levels below 10ug/dL, researchers have found subtle but dangerous deficits in learning and behavior. A recent study conducted at Children's Hospital Medical Center in Cincinnati found slight, but detectable, impairment at levels as low as 5ug/dL, half the current standard used for determining elevated lead levels. In addition, each increase of 1ug/dL was found to cause a 1% decrease in children's reading scores.

Along with causing learning problems, lead can have other adverse health effects as well, such as increases in ADD/ADHD symptoms, violent behavior, and drug use, studies have shown. (See for additional information)

Editor's note: This aforementioned Web site is down below.

Are the Alleged Benefits of Fluoridation Worth the Risk?

"Even if fluoridation does provide some modest benefit in regard to tooth decay, society really needs to take a good hard look at its priorities here," says Paul Connett, Ph.D., of the Fluoride Action Network (FAN), an international coalition of organizations helping to raise awareness of fluoride's health and environmental hazards.

"With rates of ADD/ADHD at record levels and still rising, is a minute benefit to teeth worth the risk of higher lead levels?" asks Connett.

"In fact, several recent studies have shown that rates of tooth decay do NOT rise after water fluoridation is stopped, but may actually decrease. If people want to take the gamble with fluoride (a known enzyme poison) it makes more sense to do as the Europeans do, and use topical fluoride instead," he maintains.

Untested Chemical

"Most people would be shocked to learn that there have been no adequate studies of long-term low-level exposure to silicofluorides," states Masters. "Even the EPA admits it has no data on the health and behavioral effects of SiFs."

"Shouldn't we stop intentionally exposing 140 million Americans to an untested chemical until the risks are extensively and objectively evaluated by independent researchers?" asks Dr. Masters.

For additional information on the latest study, as well as other related information, go to

Source: Neurotoxicology 2000; 21: 1091-1100


Roger Masters, PhD, Foundation for Neuroscience and Society, Dartmouth College, phone: 603-646-2153, email: (Questions related to fluoride -- lead association)

Paul Connett, PhD, Fluoride Action Network, St. Lawrence University, Phone: 315-379-9200, Fax: 315-379-0448, Email: or, URL: (Questions related to fluoride or water fluoridation)

Additional Information on this issue:

See for this information:

Fluoride Action Network
   Association of Silicofluoride Treated Water with Elevated Blood Lead   

      The Foundation for Neuroscience and Society is devoted to exploring the links between discoveries in the structure, function, and biochemistry of the brain and human social behavior. Of particular importance are behavioral dysfunctions including such common problems as hyperactivity (ADHD), violent crime, cognitive deficits, and chronic fatigue syndrome, all of which have become widespread and yet have been difficult to diagnose or treat.

News Release from Dartmouth College:

Contact: Sue Knapp -

Abstract of study:

NeuroToxicology 21(6): 1091-1100, 2000

Association of Silicofluoride Treated Water with Elevated Blood Lead

R.D. Masters, M.J. Coplan, B.T. Hone J.E. Dykes

Foundation for Neuroscience and Society, Dartmouth College, Hanover, NH 03755-3547, USA.


Previous epidemiological studies have associated silicofluoride-treated community water with enhanced child blood lead parameters. Chronic, low-level dosage of silicofluoride (SiF) has never been adequately tested for health effects in humans. We report here on a statistical study of 151,225 venous blood lead (VBL) tests taken from children ages 0-6 inclusive, living in 105 communities of populations from 15,000 to 75,000. The tests are part of a sample collected by the New York State Department of Children's Health, mostly from 1994-98. Community fluoridation status was determined from the CDC 1992 Fluoridation Census. Blood lead measures were divided into groups based on race and age. Logistic regressions were carried out for each race/age group, as well as above and below the median of 7 covariates to test the relationship between known risk factors for lead uptake, exposure to SIF-treated water and VBL > 10ug/dL. RESULTS: For every age/race group, there was a consistently significant association of SiF treated community water and elevated blood lead. Logistic regressions above and below the median value of seven covariates show an affect of silicofluoride on blood lead independent of those covariates. The highest likelihood of children having VBL > 10ug/dL occurs when they are both exposed to SiF treated water and likely to be subject to another risk factor known to be associated with high blood lead (e.g. old housing). Results are consistent with prior analyses of surveys of children's blood lead in Massachusetts and NHANES III. These data contradict the null hypothesis that there is no difference between the toxic effects of SiF and sodium fluoride, pointing to the need for chemical studies and comprehensive animal testing of water treated with commercial grade silicofluorides.

PMID: 11233755

Excerpts from the study:

"Chronic, low-level dosage of silicofluoride (SiF) has never been adequately tested for health effects in humans."

"The highest likelihood of children having [venous blood lead] VBL>10g/dL occurs when they are both exposed to SiF treated water and likely to be subject to another risk factor... "

"These data contradict the null hypothesis that there is no difference between the toxic effects of SiF and sodium fluoride, pointing to the need for chemical studies and comprehensive animal testing of water treated with commercial grade silicofluorides."

"Over 91% of US fluoridated water is treated with either sodium silicofluoride (Na2SiF6) or fluosilicic acid (H2SiF6) ­ henceforth, the silicofluorides or SiFs. Less than 10% is treated with simple sodium fluoride (NaF)."

"Though it is theoretically possible that there could be no effect, this conclusion seems unlikely when evidence from the present study is combined with congruent data from other studies. Prudence dictates, moreover, that a chemical delivered by government policy to 140 million people should have been tested and shown to be reasonably safe."

"Combined with our previous studies of data for children's blood lead in Massachusetts and in the NHANES III sample these findings point to a statistically significant risk of elevated blood lead associated with chronic ingestion of water treated with SiFs."

" is not widely recognized that over 91% of fluoridated water has been treated with sodium silicofluoride or fluosilicic acid."

"...the familiarity and widespread use of fluoridated toothpaste is not evidence of SiF safety."

"Despite MSDS data, water plant managers and health agency personnel have little understanding of the toxic properties and behavior of the SiFs."

"..extensive tests on animals exposed to sodium fluoride in their diets have never been replicated by exposure to commercial grades of sodium fluosilicate or fluosilicic acid."

"...researchers customarily employ simple sodium fluoride in animal studies and extrapolate the results to humans ingesting silicofluoride treated water...this practice is reinforced by the habit of discussing "fluoridation" without any reference to the chemicals used."

"...officials at all levels responsible for water fluoridation often appear to lack an understanding of fundamental chemical principles relating to the use of silicofluorides."

"The silicofluoride anion...must dissociate to release fluoride ion. This process is both complex and reversible, differing distinctly in many ways from release of fluoride from NaF [sodium fluoride] by simple solution/ionization."

"The only extensive examination of the actual biochemical effects of SiF that we have encountered is a German study ­ to our knowledge never cited before in the debates surrounding water fluoridation in the U.S. This research, which shows substantial changes in membrane permeability and enzymatic changes capable of substantially modifying neuronal excitability, suggests plausible chemical mechanisms that would be consistent with our empirical findings."

"...the extent of subtle health effects associated with long term exposure to SiF is thus still unknown."

"Apart from the possibility of direct toxicity, freshly released monomeric silicic acid as well as fluoride ion bind calcium. If diets are low in...calcium, the products of silicofluoride dissociation can exacerbate the competition between calcium and lead for bone and soft tissue sites. In addition, F- has a high affinity for proteins and is known to modify enzyme action with potential for disrupting a wide range of endocrine, immune, and neural processes. It has also been implicated in disturbing the functionality of calcium, both directly and indirectly in interaction with vitamin D."

"Studies of the long-term effects of exposure to fluorides in general and silicofluorides in particular must therefore take into account the strong possibility of multiple pathways and diverse mechanisms of intoxication. Even more important, recent biochemical findings link lead uptake in the brain to the replacement of zinc by lead in synaptotagmen, thereby changing its folding and greatly reducing its functional effectiveness. Such new research apparently provides a precise neurochemical explanation for the well-known link between lead and lower cognitive ability and illustrates radically new methods to analyze lead neurotoxicity."

"In light of these facts and hypotheses, the congruent statistical findings from three populations totaling almost 400,000 children...indicate an urgent need for further study of the possible links between exposure to SiF and increased lead uptake as well as the behavioral dysfunctions associated with lead neurotoxicity."

"Given the paucity of direct knowledge about biomechanisms depending on exposure to commercial silicofluorides, and the magnitude of the potential risks ­ especially to poor and minority children ­ large scale epidemiological studies, chemical analyses, and animal experimentation on silicofluorides and their effects deserve the highest priority."

Previous Studies by Masters and Coplan:

The previous studies by Masters and Coplan included data from 238,000 children from Massachusetts and about 4,000 children in the Third National Health and Nutrition Evaluation Survey.

Masters RD, Coplan MJ. Water treatment with silicofluorides and lead toxicity. Int J of Environ Stud 1999; 56: 435-449. -

Masters RD, Coplan MJ. A dynamic, multifactorial model of alcohol, drug abuse, and crime: Linking neuroscience and behavior to toxicology. Social Science Information 1999; 38: 591-624.

For more information about the Cognitive Function/lead toxicity link:

Moon C et al. Main and interaction effects of metallic pollutants on cognitive functioning. J Learn Disab 18 (4):217-21, 1984

Lewis et al. Prenatal exposure to heavy metals: effect on childhood cognitive skills and health status. Ped 1992;89:1010-15

Weiss B, Landrigan PJ. The developing brain and the environment: an introduction. Environ Health Perspect 2000 Jun;108 Suppl 3:373-4.

Even at levels below the 10µg/dL some researchers find subtle but dangerous deficits in learning and behavior. ­ Reuters Health ­ March 14, 2001- (A recent study at Children's Hospital Medical Center in Cincinnati found that slight, but detectable, impairment was found at levels as low as 5µg/dL, or half the current standard used for determining elevated lead levels. In addition, each increase of 1µg/dL was found to cause a 1% decrease in reading scores.)

Kids at Risk: Chemicals in the environment come under scrutiny as the number of childhood learning problems soars ­ US News and World Report ­ Cover Story - 6/19/00 -

For more information about the ADHD/lead toxicity link:

Brockel B et al. Lead, attention, and impulsive behaviour: changes in a fixed ratio waiting for reward paradigm. Pharmacolo Biochem Behav.1998;60:545-52

Rice DC. Parallels between attention deficit hyperactivity disorder and behavioral deficits produced by neurotoxic exposure in monkeys. Environ Health Perspect 2000 Jun;108 Suppl 3:405-8

In Harm's Way: Toxic Threats to Child Development. -

The Hyperactivity Hoax, by Dr. Sidney Walker, St Martin's Press, 1998 ­ Dr. Walker shows that lead poisoning is one of the factors that can produce hyperactivity (ADHD).

For more information about the violence/lead toxicity link:

Pihl RO et al. Lead and cadmium levels in violent criminals. Psych Rep. 66(3 Pt1):839-44, 1990

Nevin R. How lead exposure relates to temporal changes in IQ, violent crime, and unwed pregnancy. Environ Res. 2000 May;83(1):1-22.

Chemicals and Crime: A Truly Toxic Effect. Washington Post. Judy Mann. May 26, 2000; C11. -

For more information about lead toxicity:

The Alliance to End Childhood Lead Poisoning - - Founded in 1990, the Alliance is a national public interest organization formed by leaders in public health, environmental protection, affordable housing, and civil rights to protect all children from lead poisoning. The Alliance was designed to have the technical capacity and comprehensive reach across disciplines needed to effect change.

CDC Childhood Lead Poisoning Prevention Program -

Needleman H. The current status of childhood low level lead toxicity. Neurotoxicology. 1993;14:161-6

Moss ME, Lanphear BP, Auinger P. Association of dental caries and blood lead levels. JAMA 1999 Jun 23-30;281(24):2294-8. Comment in: JAMA 1999 Jun 23-30;281(24):2340-2.

Additional Quotes:

Paul Connett, PhD (Fluoride Action Network) ­ "There are MANY important issues currently facing minority communities in the US, and it is certainly understandable that opposition to water fluoridation has not been a very high priority. However, I hope that these recent studies showing an association with elevated blood lead levels might motivate some in the African American and Hispanic communities to get involved in the struggle to end this dangerous experiment."

Roger Masters, PhD (Dartmouth College, Foundation for Neuroscience and Society)

"If further research confirms our findings, this may well be the worst environmental poison since leaded gasoline."

"Our research needs further laboratory testing...This should have the highest priority because our preliminary findings show correlations between SiF use and more behavior problems due to known effects of lead on brain chemistry."

"While statistics on learning disabilities are notoriously poor, the existing fragmentary data are consistent with the possibility that the combination of lead pollution and silicofluorides increases the proportion of children with learning problems."

"Governmental policy-makers erroneously claim there is no difference between SiFs and sodium fluoride, whereas several studies have showed that SiFs have very different chemical and biological effects."

"In particular, experiments in Germany have revealed that SiFs are 'cholinesterase inhibitors' ­ a class of chemicals that include organophosphate pesticides, sarin nerve gas, and other toxins associated with such poorly understood health problems as Gulf War Syndrome, chronic fatigue syndrome, memory loss, and fibromyalgia. Shouldn't we stop intentionally exposing 140 million Americans to such dangerous chemicals until the risks are extensively and objectively evaluated by independent researchers?"

Miscellaneous Information:

The chemicals known as silicofluorides (SiF) include both fluosilicic acid (H2SiF6) or sodium silicofluoride (Na2SiF6).

Studies Showing No Increases in Dental Decay Rates Following Cessation of Fluoridation (exerpts in italics):

Patterns of dental caries following the cessation of water fluoridation. (Community Dent Oral Epidemiol 2001 Feb;29(1):37-47) ­ The prevalence of caries decreased over time in the fluoridation-ended community while remaining unchanged in the fluoridated community.

Caries Trends 1992-1998 in Two Low-Fluoride Finnish Towns Formerly with and without Fluoridation (Caries Res 2000 Nov;34(6):462-468) - The fact that no increase in caries was found in Kuopio despite discontinuation of water fluoridation and decrease in preventive procedures suggests that not all of these measures were necessary for each child.

Decline of caries prevalence after the cessation of water fluoridation in the former East Germany (Community Dent Oral Epidemiol 2000 Oct;28(5):382-9) - In contrast to the anticipated increase in dental caries following the cessation of water fluoridation in the cities Chemnitz (formerly Karl-Marx-Stadt) and Plauen, a significant fall in caries prevalence was observed... further support for the contention that caries prevalence may continue to fall after the reduction of fluoride concentration in the water supply from about 1 ppm to below 0.2 ppm F.

Caries prevalence after cessation of water fluoridation in La Salud, Cuba (Caries Res 2000 Jan-Feb;34(1):20-5) - In 1997, following the cessation of drinking water fluoridation, in contrast to an expected rise in caries prevalence, DMFT and DMFS values remained at a low level for the 6- to 9-year-olds and appeared to decrease for the 10/11-year-olds (from 1. 1 to 0.8) and DMFS (from 1.5 to 1.2). In the 12/13-year-olds, there was a significant decrease (DMFT from 2.1 to 1.1; DMFS from 3.1 to 1. 5), while the percentage of caries-free children of this age group had increased from 4.8 (1973) and 33.3 (1982) up to 55.2%.

The decline of caries in New Zealand over the past 40 years (N Z Dent J 1998 Sep;94(417):109-13) - an explanation of the convergance of caries prevalence in fluoridated and non-fluoridated areas since the 1970s may require a re-assessment of the fluoride effect. This convergence, and the overall decline during the last decade without known additional fluoride supplementation, suggest that factors other than fluoride... may have contributed.

Caries frequency in permanent teeth before and after discontinuation of water fluoridation in Kuopio, Finland (Community Dent Oral Epidemiol 1998 Aug;26(4):256-62) - In spite of discontinued water fluoridation, no indication of an increasing trend of caries could be found in Kuopio.

Caries decline in Germany--causes and consequences (Gesundheitswesen 1997 Dec;59(12):710-5) - Contrary to the predicted caries increase, a caries decline in the juvenile population could be proven by epidemiological comparative studies.

Rise and fall of caries prevalence in German towns with different F concentrations in drinking water (Caries Res 1997;31(3):166-73) - There was a significant caries decrease down to the lowest DMFT (2.0) since 1959 in spite of the fact that only F-poor water was available over years in both towns.

The Mystery of Declining Tooth Decay (Nature July 1986 Vol. 322) - Large temporal reductions in tooth decay, which cannot be attributed to fluoridation, have been observed in both unfluoridated and fluoridated areas of at least eight developed countries over the past thirty years.

Recent Press Reports on Fluoridation:

Arizona Daily Sun - "Fluoride" - March 12, 2001

Clean water advocates in states, such as New Hampshire, are trying to pass laws requiring that all chemicals, especially fluoride, that are put in drinking water be tested to ensure that they don't contain harmful contaminants like heavy metals. ­ "What Evidence Is There That Water Fluoridation Prevents Cavities?" - Feb. 15, 2001 -

[P]ublic health policy in this country has allowed water fluoridation to continue in the absence of solid scientific evidence that its benefit is greater than its risk... When you commit to putting a powerful chemical into the water supply, you'd better have the best of evidence that it is both safe and effective. The required level of evidence is just not there.

Reuters Health ­ "Fluoridated Water: Some Say it is Unnecessary" ­ Feb. 16, 2001 -

If...the effects of the cessation of water fluoridation are not readily detectable due to other existing sources of the element--or better treatment--the continued practice of fluoridation is therefore unnecessary...

Irish 20/20 News Program ­ "Hard to Swallow? The Water Fluoridation Debate" ­ Jan. 12, 2001 -

98% of Europe does not drink fluoridated water. Apart from 10% of the UK and 3% of Spain, virtually every European country has either stopped, rejected outright, or even banned water fluoridation as a health program.

New Hampshire Sunday News ­ "Arsenic in the water: Benefits vs. dangers" -

Arsenic, the legendary king of poisons, is being added to drinking water in ... communities that fluoridate. The cancer-causing metallic element is among the contaminants found in hydrofluosilicic acid, which is used to deliver tooth decay-preventing fluoride to Manchester's drinking water.

Santa Barbara News Press ­ "Fluoride fantasy" ­ Feb. 2, 2001 -

...a growing body of research has raised serious questions about long-term fluoride use, indicating it may cause health problems such as cancer, mental impairment, brittle bones and fluorosis...

Willamette Week (Oregon) ­ "The F Word" ­ Feb. 21, 2001 -

Proponents of fluoridation argue that thousands of studies since 1950 have put questions about the safety of water fluoridation to rest. But if anything, the questions keep growing...In the last six months, the British and Canadian governments both released wide-ranging reports that reviewed the thousands of published scientific studies on water fluoridation...The British review was the most comprehensive ever done of fluoride science. The Canadian review, which looked at a different set of studies, reached the same conclusions as the British. Both directly challenged the conventional wisdom on fluoride in the United States.

Healthmall - Fluoride "Bad to the Bone" ­ Feb. 14, 2001 -

...increasing exposure to fluoride may be a contributing factor to the near epidemic levels of arthritis now found in the US....


The Journal of History - Fall 2002 Copyright © 2002 by News Source, Inc.