The Fluoride Controversy: The Facts & The Fiction
Fluoride Position Paper
Paul G. Rubin, DDS, MIAOMT, March, 2008
There is a great deal of controversy about the effectiveness and the safety of fluoride, especially in the form of water fluoridation. The intent of this paper is to provide you with information you will need to make an informed decision about fluoride. This information is based on valid scientific sources, and its basic premise of is that water fluoridation is ineffective at improving dental health, and does have the potential of adverse health effects (in other words, harm).
History of fluoridation
Water fluoridation began in the late 1940’s and 50’s after some preliminary studies were done that purportedly showed that a certain “optimal” level of fluoride (stated to be one part per million – 1ppm) in the drinking water led to decreased cavities in children. The testing protocols were quite flawed, and science gave way to politics. For a detailed history of the dubious beginnings of water fluoridation in this country, see The Fluoride Deception, by Christopher Bryson. (1)
Water fluoridation soon became a public health policy priority and has been heavily promoted ever since. Today, the American Dental Association (ADA) proclaims that, “Based on the overwhelming weight of peer-reviewed, credible scientific evidence, the ADA has long supported community water fluoridation as a safe, effective means of preventing tooth decay." (2) Is that truly the case? If we look at science rather than “proclamations” or endorsements, the story is different. Large scale, broad based, well controlled epidemiologic studies published in peer-reviewed medical or scientific journals show no substantial statistical difference between fluoridated and non-fluoridated communities. This fact will shock some, but let’s look at the science.
The largest survey ever conducted in this country was commissioned by the National Institute of Dental Research (NIDR) in 1987. In this study, Brunelle and Carlos (3) looked at 39,000 children in 84 communities. The average difference in tooth decay in children aged 5-17 years who had lived all their lives in fluoridated vs. non-fluoridated communities was not statistically significant! Using an index called DMFS, which means counting decayed, missing, and filled surfaces of teeth, the actual difference was less than one half of one percent. Similarly, a study done in Washington State in 1996 (4) looked at caries prevalence in 3,000 third grade children in 39 counties throughout the state. Their statistics were almost identical to the Brunelle study, and the investigators reported, “This study did not find a statistically significant effect of water fluoridation.” They did find a significant correlation between decay and economic status, which is a finding that should be pursued.
The World Health Organization gathered data in 2001 (5) on tooth decay trends over the last several decades in twenty different countries. They found that there has been a significant decline in decay in 12 year olds since about the early 1970’s. What is more interesting is that this decline is virtually the same in countries that are fluoridated, partly fluoridated or totally non-fluoridated.
The mechanism of fluoride’s effects
There are pervasive notions and assumptions about how fluoride supposedly works that persist in the public and even in the dental profession, in spite of evidence to the contrary. Most dentists were taught in dental school that ingested fluoride will incorporate into the developing tooth enamel of a child and make the teeth more resistant to decay. Furthermore, topically applied fluoride would create an enamel surface more dense with fluoride ions and more resistant to the decay-causing acids produced by plaque bacteria.
What does research really show? Featherstone and other prominent researchers on fluoride have found that ingested fluoride does not significantly reduce decay, and that fluoride’s primary effect is topical. Their studies have found that the level of fluoride incorporated into dental mineral by systemic ingestion is insufficient to play a significant role in caries [decay] prevention. (6,7) So, if ingested fluoride doesn’t do any good, why are we drinking it, and why are some physicians still prescribing fluoride supplements for infants and children? One noted authority, Dr. Paul Connett, has stated that “ingesting fluoride for cavity prevention makes about as much sense as swallowing sun block to protect the skin from sunburn". (8)
What, then, about the topical effect? Some have postulated that drinking fluoridated water will lead to fluoride in the saliva continually bathing the teeth and protecting them. Research has shown that there is, in fact, a higher amount of fluoride in the saliva where water is fluoridated vs. non-fluoridated areas, but in both cases the concentration is very low: 0.016ppm vs. 0.006ppm. Researchers have concluded that “This concentration of fluoride is not likely to affect cariogenic [cavity-causing] activity". (9) What about topically applied fluoride in the dental office, or with fluoride rinses, in order to create a more fluoride-dense enamel surface (a goal that dentists have always strived for)? In Fluorides in Dentistry, Clarkson, Fejerskov and others state that “The prevalence of dental caries in a population is not inversely related to the concentration of fluoride in enamel. (10) In other words, higher fluoride level on the enamel surface does not equate with fewer cavities. Other researchers have found “a higher concentration of enamel fluoride is not necessarily more efficacious in preventing dental caries. (11, 12) These studies are cited in the Centers for Disease Control (CDC) report of August, 2001. (13) Featherstone reports in a cover story for the Journal of the ADA in July of 2000: “Even when the outer enamel has higher fluoride levels, such as 1000 ppm, it does not measurably withstand acid-induced dissolution any better than enamel with lower levels of fluoride ". (14)
Good, credible research, then, blows these old myths apart. Science, it seems, rather than providing an explanation of how fluoride works, actually provides a pretty good explanation of why fluoride doesn’t work. Why, then, do these old assumptions about fluoride still persist?
What about the safety of fluoridation?
“Fluoridation as a health policy] is against all principles of modern pharmacology. It’s really obsolete … I think those nations that are using it should be ashamed of themselves. It’s against science.”
“Over the past ten years, a large body of peer-reviewed science has raised concerns that fluoride may present unreasonable health risks particularly among children, at levels routinely added to tap water in American cities.”
“The whole thing is politics. You’re not talking science at all.”
There have been studies linking fluoride exposure with a number of health concerns. Disruption of thyroid function, increased hip fracture in the elderly, early stages of skeletal fluorosis, decreased IQ level in children (in some recent studies in China), disfiguring dental fluorosis, suspicion of increased incidence of bone cancer in young males, all have found their way into the scientific literature. (15) Can any of these health effects occur at levels of fluoride exposure one would get from drinking fluoridated water? This is a crucial question, and one that is at the center of a recent report from the National Research Council (NRC). Below is the story of how the highest authorities in science in this country cast serious doubt on the safety of water fluoridation.
The National Research Council (NRC) report of 2006 and the U.S. Environmental Protection Agency (USEPA)
The USEPA does not oversee or regulate water fluoridation programs. It is, however, responsible for setting and monitoring “maximum contaminant levels” of substances in our drinking water. To protect public health and safety, EPA standards dictate the maximum allowable limit of lead, arsenic, fluoride, etc. that drinking water can contain. Above those levels (called MCLG or “maximum contaminant level guidelines”), these are known to have adverse health effects. Such contaminants have to be removed from water to keep them below the MCLG levels. Fluoride is considered by toxicologists to be more toxic than lead and only slightly less toxic than arsenic. (16) The MCLG’s for lead and arsenic, interestingly, are listed in a few parts per billion. For fluoride, the MCLG has been 4,000 parts per billion (or 4ppm)! It’s important to note that the MCLG of 4ppm is uncomfortably close to the “optimal” level recommended of 1ppm.
The NRC, which is a branch of the National Institutes of Health, was commissioned by the EPA in 2003 to review current scientific research and determine whether the current MCLG standard of 4ppm is still appropriate. After three years, the expert panel of the NRC released its 450 page report (March, 2006). (17) They stated quite clearly that the current level of 4ppm is too high and should be lowered to protect public health. It was not the panel’s job to look at effectiveness of fluoride, nor was it given the job of stating what this new level of MCLG should be. They referred it back to the EPA to do a risk assessment and come out with a new, lower MCLG level consistent with current research. The panel’s review of current science (the health concerns mentioned above and more) concluded that adverse health effects can indeed happen at 4ppm.
One of the panelists, Dr. Kathleen Thiessen, stated in a later interview that “I personally do not think that a responsibly set MCLG would be high enough to allow for water fluoridation . . . information presented in the report indicates a safe MCLG for fluoride would be less than 1ppm.” She also stated that she is not the only one on the panel with doubts about the safety of water fluoridation. An MCLG set at 1ppm would, of course, mean that public water fluoridation programs are set at a level known by the U.S. government to be harmful! As you might guess, this is going to be a very politically charged issue. As of early 2008 (nearly two years after the release of the NRC report), the EPA has yet to change the MCLG level. Unfortunately, where science and politics conflict, sometimes science loses out. It will be very interesting to see when and how the EPA comes out with its revised MCLG value.
In light of the above information and the yet to be released new MCLG level, it would seem prudent to halt any new fluoridation programs until the USEPA releases its findings. To knowingly continue to promote fluoridation when the “jury is still out” about a safe maximum contaminant level is scientifically and morally unsound.