The Distorted Science on Fluoridation

I am grateful to Dr. Plunkett for this useful article. The material on supposed IQ effects is especially good. However, I think it will not be persuasive on some of its points. 1) One point is flat wrong. Dr. Plunkett claims that it is "blatantly untrue" that "fluoride is a by-product of the fertilizer industry." In fact the CDC source cited by Dr. Plunkett at note shows just that. It says that fluorosilicic acid (FSA) and its dry forms are the main water fluoridation additives and that "[a]pproximately 95% of the FSA used for water fluoridation comes from this process," referring to the release and capture of gaseous fluorides, when fluorite rock is heated to release a calcium phosphate-gypsum slurry used to make phosphate fertilizer. Dr. Plunkett says that "fluoride is a mineral found in nearly all water sources." This is wrong. Fluorine (not -ide) is an element which is highly reactive and does not occur naturally in isolation at the temperatures supporting human life, but rather exists in a range of chemical compounds, including many different fluorides. Some of those compounds are produced by human activity, including fluorosilic acid, which does not occur without human induced chemical processes. The underlying scientific ignorance here is the assumption that human produced chemicals are inherently different from natural ones, and bad, and likewise that industrial chemical by-products should carry a stigma. More specifically it is that the fluorine absorbed and metabolized from fluorosilicic acid is somehow different from other fluorine. In fact it is all the same fluorine. Fluorosilicic acid's natural chemistry leads it to break down further and recombine, forming in part the fluorapatite that is also an inherent natural part of tooth enamel, that is absorbed in remineralization processes that impede tooth decay. In high concentrations fluorosilicic acid and other fluorides are dangerous toxic chemicals, as fluoridation opponents point out. On the other hand, absence of dietary fluorine absorbed in consumed fluorides is a nutritional deficiency, that weakens bones as well as teeth. Neither of those extremes is directly relevant to the questions of safety, and efficacy, (which are separate) of consumption of fluoridated water at the levels widely used, and now planned in Portland, to reduce dental caries and promote health. Some Portland fluoridation opponents have asserted that the fertilizer company ability to profit from fluorosilicic acid as an industrial byproduct has driven fluoridation. They have not to my knowledge shown that fertilizer interests are behind fluoridation anywhere, and certainly not in Portland. They have suggested that the toxicity of the byproduct is a motive for the fertilizer companies to want to get rid of it, but the way fluorosilic acid breaks down does not support that reasoning. 2) On the National Research Council 2006 report: The panel participants had some significant disagreements. Fluoridation skeptics or opponents frequently cite the testimony to Congress of a Dr. Thiessen, who was participant in the NRC panel, in particular. Her testimony is treated seriously by scientifically trained and literate public health-oriented doctors concerned with environmental health and toxic pollution with whom I have been in communication. Intellectual honesty and scientific integrity demands that the existence of such skepticism be recognized. It also demands clarity that her view remains a minority view, as reflected in the overall conclusions Dr. Plunkett cites. 3) The fact that 18,000 water systems fluoridate will not persuade opponents, who interpret it as an established material interest that obstructs recognition of what they regard as true science. I am not sure that is entirely false. As opponents and skeptics point out, use of fluoride compounds in municipal water began before the FDA established safety and effectiveness standards for chemical additives and fluorides were grandfathered in as not requiring such examination. If fluoridation were to prove really to be a problem, it would be a huge and difficult reversal and admission to make for a lot of people, organizations and institutions who have been committed to it. I don't think the state of the science now, even the skeptical science, justifies the claim that such interests are what keeps fluoridation going, however. From a political point of view, seeking FDA review might take that particular arrow from the opponents' quiver. Absent that, the opponents will just say that the large number of governments fluoridating water is an historical artifact of a policy pursued in ignorance at a time when many other chemical practices now rejected as health hazards were also tolerated. On the other hand, in the last 15 or 20 years the public health authorities have revised downward the levels of fluoride additives deemed safe. This is a substantial issue that forms part of wider debates within public health about "safe" levels of toxic chemicals. Neither side of the most prominent forms of public debate about fluoridation really address this issue adequately in my view. It forms a legitimate scientific basis within environmental health science for not dismissing those with questions out of hand. ------ The larger problem here is that some of the biggest questions about fluoridation are not scientific but ethical. a) First, within the science there is a need to deal with safety and risk, and efficacy, and how they relate to one another. The greatest power of scientifically honest anti-fluoride arguments comes from the combined claims that fluoride ingested in drinking water is both more risky and less effective than topical applications, due to problems controlling doses and bio-accumulation, and because the remineralization effects of fluoride derive from topical contact, which is limited in drinking water. I do not believe those arguments can or should be dismissed out of hand, though the evidence I have seen comes nowhere near to proving substantial risk or disproving efficacy, as some opponents claim. b) The primary ethical claims and motivation for water fluoridation are health equity and the promotion of public health and prevention of ill health in a more equitable manner. Dr. Plunkett writes "Fluoridated water is the most effective, affordable way to provide essential dental protection for everyone." I believe that the questions of effectiveness and affordability need to be separated and examined in relation to equity. What if water fluoridation is most affordable, but not really the most effective way to get low-income kids fluoride treatment to inhibit tooth decay? Does this amount to low-balling our health equity commitments. To trying to do something, but on the cheap? To putting cost above equity? There is serious scientific evidence that intensive topical treatment is more effective than fluoridated drinking water. I don't know if there is enough such evidence to be dispositive on that question. Such methods would not expose anyone to whatever risks arise from ingestion of fluorides in water, low as those risks may be. I am not sure how the costs of providing topical treatments to low-income kids would compare to those of fluoridating the water of the whole population. But if we are serious about health equity, it seems at least worth bringing that question into the discussion. I have not seen it discussed in public in Portland. c) In contrast to the health equity arguments, which opponents ignore too much, there are important arguments about scientistic paternalism and choice in risk. There are other areas than fluoridation in which I believe that economic interests have corrupted the application of science to regulation of health risks, in particular to consumer choice in evaluating how they wish to act with regard to unquantified or uncertain risks. The treatment of unquantified or uncertain risks as "no risk," as if "not known" means "doesn't exist," is intellectually dishonest and poor science in my view. Examples for me include bovine growth hormone in milk, where I believe issues of endocrine disruption have not been adequately dealt with by regulators, and a different set of environmental concerns about genetic modification of plants and animals, where I am less concerned with about consuming GMO food hurting my personal health, than I am with issues of potential ecosystem change, and more general effects of industrial monoculture being intensified. So although I don't share most of the fears of many opponents of fluoridation, I take seriously their desire to have control over their choices of risks. (My perspective arises because I grew up with fluoridated water which did not produce the effects they fear in my home town, but also because I would nonetheless have been part of the "bad teeth" statistics, given my number of cavities as a child. Neither is a scientific argument of course.) I do not think that either the issue of scientistic paternalism or that of individual choice in risk, nor the question of how we should relate them to health equity issues, have been adequately engaged in Portland. d) The most disturbing aspect of the anti-fluoridation campaigning in Portland to me actually is not the prevalence of poor scientific argument and evidence, though that does bother me. It is the frequent motives aspersions against those who favor fluoridation, which range from the ridiculous (desire to poison), to the illogical (if dentists were solely motivated by profit, they would not try to prevent dental caries, but just make money treating it and its consequences), to the offensive because of lack of evidence (the accusation of venality generally, and the imputation more particularly of corruption of officials and public health advocates by corporate money). On the other hand, pro-fluoride argumentation often is deeply shaped by scientistic paternalism and dismissal of opposition a merely ignorant, and/or driven by nutty conspiracy theories. Those are also forms of illegitimate and insulting motives argument. I think that kind of paternalism is frankly stupid. It only deepens the opposition. It is infuriating to people and makes them question the motives of those who are insulting and patronizing them. A real scientific attitude is not authoritarian. It favors education and the spread of the best current knowledge, while acknowledging that best knowledge changes. I can't say that I think either side of the limited "debate" in Portland has been characterized by that attitude. I hope that proponents will take up the task of engaging the fears and worries of opponents calmly, and much more seriously, with a real scientific attitude, and not just authoritarian paternalism, including consideration of contrary evidence when it is real, as opponents' efforts to overturn the recent decision evolve, and as implementation draws nearer.

First, I want to thank you for providing references to many of your statements, as most (on both sides) do not. What you have failed to discuss in your opinion piece is that most Americans, and especially American children, are already receiving too much fluoride. The CDC (1) reports that 41% of American children ages 12-15 now have some form of dental fluorosis. Whether or not you believe the claim that this is “only a cosmetic effect,” the undisputed fact is that dental fluorosis is a visible sign of fluoride overexposure. In 2010, EPA (2) published the most recent fluoride exposure analysis. Astonishingly, EPA refused to even consider infants less than 6 months, as this age group was not considered a “sensitive subpopulation.” Nevertheless, children under the age of 7 were found to have total fluoride intake estimates similar to, or that exceeded the Tolerable Upper Intake Level (UL) for fluoride set by IOM in 1997: • <0.5 years (calculated from data provided): intake=1.11 mg/day (UL=0.7 mg/day) • 0.5-<1 year: intake=1.21 mg/day (UL=0.9 mg/day) • 1-<4 years: intake=1.58 mg/L (UL=1.3 mg/day) • 4-<7 years: intake=2.03 mg/day (UL=2.2 mg/day) EPA (2) concluded “it is likely that most children, even those that live in fluoridated communities, can be over-exposed to fluoride at least occasionally” (p.109). As for the National Research Council’s 2006 report (3) not being relevant to artificial fluoridation, NRC panelists have made the following statements: • “What the committee found is that we’ve gone with the status quo regarding fluoride for many years—for too long, really—and now we need to take a fresh look. In the scientific community, people tend to think this is settled. I mean, when the U.S. surgeon general comes out and says this is one of the 10 greatest achievements of the 20th century, that’s a hard hurdle to get over. But when we looked at the studies that have been done, we found that many of these questions are unsettled and we have much less information than we should, considering how long this [fluoridation] has been going on.” -Dr. John Doull, NRC Panel Chair (4) • “The NRC report is relevant to many aspects of the water fluoridation debate… [T]he report discusses the wide range of drinking water intake among members of the population, which means that groups with different fluoride concentrations in their drinking water may still have overlapping distributions of individual fluoride exposure. In other words, the range of individual fluoride exposures at 1 mg/L will overlap the range of individual exposures at 2 mg/L or even 4 mg/L. Thus, even without consideration of differences in individual susceptibility to various effects, the margin of safety between 1 and 4 mg/L is very low.”
- Dr. Kathleen Thiessen, NRC Panel Member (5) • “In my opinion, the evidence that fluoridation is more harmful than beneficial is now overwhelming and policy makers who avoid thoroughly reviewing recent data before introducing new fluoridation schemes do so at risk of future litigation.”
- Dr. Hardy Limeback, NRC Panel Member (6) You go on to refer to the Harvard (2012) study as “methodologically flawed, not relevant to water fluoridation in the U.S., or not peer-reviewed by independent scholars.” The Harvard study (Choi, 2012; 7) was published in Environmental Health Perspectives. This is not only a peer-reviewed journal, but is a publication of the US National Institute of Environmental Health Sciences (NIEHS), of the National Institutes of Health (NIH), which is in turn a part of the Department of Health and Human Services (DHHS). (8) To clarify, only one of the studies examined fluoride levels at 11.5 mg/l. The majority of studies examined by the Harvard team investigated fluoride levels below the current MCLG set by US EPA for fluoride (4 mg/L; Note: NRC (2006) insists this level is not safe, and should be lowered). Furthermore: • One study, sponsored by UNICEF, found reduced IQ at just 0.88 mg/L – a level within the “optimal” fluoride range added to the drinking water of over 200 million Americans; • Seven studies found reduced IQs among children drinking water with fluoride levels between 2.1 and 4 mg/l — levels that 1.4 million Americans drink everyday; • Four studies found effects at levels between 1.8 and 2.0 mg/l — levels that over 200,000 Americans drink everyday. Other statements from your piece that deserve rebuttal include the following: MP: “Another junk science claim is that fluoride is a by-product of the fertilizer industry. This is blatantly untrue.” According to the National Research Council (2006), “The most commonly used additives [for artificial fluoridation] are silicofluorides, not the fluoride salts used in dental products (such as sodium fluoride and stannous fluoride). Silicofluorides are one of the by-products from the manufacture of phosphate fertilizers.” (p.15) MP: “At a time when Oregon children have one of the nation’s highest rates of untreated tooth decay, fluoridation is a smart strategy for Portland.” Statistically speaking, this argument makes no sense. According to the 2007 Oregon Smile Survey (9), “School children who live outside of the Portland metropolitan area experience more tooth decay, more untreated decay, and more decay severe enough to require urgent treatment than their urban counterparts. Children in the Portland metropolitan area have less untreated tooth decay, are less likely to have ever had a cavity and are less likely to need urgent dental treatment.” The incidence of untreated tooth decay in Portland metro children is in line with the national average (21%). (10) MP: “It [fluoride] is regulated by the U.S. Environmental Protection Agency (EPA) and must meet strict quality standards that assure the public’s safety.” According to NRC (2006), “Fluoride is one of the natural contaminants found in public drinking water supplies regulated by EPA. It is important to make the distinction that EPA’s standards are guidelines for restricting the amount of naturally occurring fluoride in drinking water; they are not recommendations about the practice of adding fluoride to public drinking-water systems.” (pp.13-14) “EPA does not regulate or promote the addition of fluoride to drinking water.” (p.18) Furthermore, while the CDC vigorously promotes fluoridation, it does not: 1) oversee the safety of the program; 2) vouch for the safety of the chemicals used; or 3) accept any other liability in the matter. Despite that the FDA considers fluoride an “unapproved new drug,” and regulates its addition to bottled water, FDA also does not claim responsibility for the fluoridation program. The National Sanitation Foundation (NSF), which you claim sets “strict quality standards that assure the public’s safety,” have the following to say regarding the Standard for drinking water treatment chemicals: “NSF shall not be responsible to anyone for the use of or reliance upon this Standard by anyone. NSF shall not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Standard.” (11) Furthermore, according to the National Sanitation Foundation Fact Sheet on Fluoridation Chemicals (12): “The results in Table 1 indicate that the most common contaminant detected in these products is arsenic, which is detected in 43% of the product samples.” The US EPA has set the Maximum Contaminant Level Goal (MCLG) for arsenic at 0 ppb—as is required for all carcinogens. Purposely adding a known carcinogen to the drinking water of all Americans is hardly good public policy. So if EPA, CDC, FDA, and NSF claim no liability, exactly who is responsible for any adverse health effects (including dental fluorosis) incurred by the public from water fluoridation? Perhaps you could get a “little help from Google” with the term “Fluoridegate.” REFERENCES: 1) CDC, 2010. http://www.cdc.gov/nchs/data/databriefs/db53.htm 2) EPA, 2010. http://water.epa.gov/action/advisories/drinking/fluoride_index.cfm 3) NRC, 2006. http://www.nap.edu/catalog.php?record_id=11571 4) Doull. http://www.waterloowatch.com/Index_files/Second Thoughts About Fluoride, Scientific American Jan-08.pdf 5) Thiessen. http://www.fluoridealert.org/uploads/thiessen-2006.pdf 6) Limeback. http://www.fluoridealert.org/news/the-evidence-that-fluoride-is-harmful-is-overwhelming/ 7) Choi, 2012. http://www.hsph.harvard.edu/news/features/features/fluoride-childrens-health-grandjean-choi.html 8) NIEHS. http://www.niehs.nih.gov/ 9) Oregon Smile Survey, 2007. http://public.health.oregon.gov/PreventionWellness/oralhealth/Documents/smile_2007.pdf 10) CDC. 2005. http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5403a1.htm#tab2 11) NSF, 2001. https://law.resource.org/pub/us/cfr/ibr/005/nsf.61.2001.html 12) NSF, 2012. http://www.nsf.org/business/water_distribution/pdf/NSF_Fact_Sheet.pdf

I was going to comment on each specific fallacy in this article, but others have already refuted most of them. One that hasn't been addressed is this comment disregarding the very real possibility that fluroidated water can decrease IQ's: "If a real link existed, America would have seen its IQ scores drop between the 1940's and 1990's, the same time many communities adopted water fluoridation. Yet the opposite happened. Over this same period, the average IQ scores in the U.S. improved by 15 points." But this argument has no merit whatsoever: First, IQ's were increasing in the decades before fluoridation just as they were after. Obviously, something else was causing the changes. It's entirely conceivable that the scores would have risen more without fluoridation. Second, there have been no studies done separating out IQ scores in people from fluoridated areas and non-fluoridated areas, or with higher and lower blood or urine levels of fluoride. These are the meaningful ways to gather significant data, not to throw everyone in together. This is exactly what the National Academy of Sciences 2006 report and the recent Harvard meta-analysis recommended. Yet not one study like this has been done in the U.S., even though studies in four different countries since the early '90's have shown that the higher the fluoride in the water, the lower the IQ. Figuring out exactly why IQ scores have been increasing is devilishly difficult and there is no consensus.There are many confounders over time, such as changes in testing, increases in parents' education, phasing out of lead paint and leaded gas, and kids' increasing familiarity with technology, media and computer games. There have been at least 21 factors identified that could play a role. It's also been interesting (and disturbing) to see that while many intelligence scores are rising, some test scores measuring creativity have been falling. By the same arguments as above, I wouldn't contend that fluoridation is causing these falling scores unless more precise testing was conducted. Bottom line: saying that rising IQ scores are proof that fluoridation doesn't lower intelligence just isn't valid.