Category Archives: Health and Medicine

Water fluoridation and dental fluorosis – debunking some myths

Dental fluorosis is really the only “negative” side effect of community water fluoridation (CWF). It occurs in non-fluoridated as well as fluoridated areas but is often a little more common in the fluoridated areas.

However, there is a lot of rubbish about dental fluorosis spouted by anti-fluoride propagandists. It is worth putting dental fluorosis into its proper context and debunking some of the misinformation they promote.

Here are some facts.

1: Diagnosis of dental fluorosis involves grading teeth into 6 levels:

  1. No dental fluorosis
  2. Questionable
  3. Very mild
  4. Mild
  5. Moderate
  6. Severe.

Here are some photos of the different grades

2: The moderate/severe grades are rare in areas considered for CWF and fluoridation does not increase prevalence of those grades of dental fluorosis. However, those more severe forms are more common in areas where dental fluorosis is endemic like parts of China, India and north Africa.

Dental and skeletal fluorosis is a real problem in these endemic areas, but it is not a problem in the areas where CWF is used.

The figure below contrasts data for prevalence of dental fluorosis in NZ and the USA where CWF is common with data for an area of endemic fluorosis in China.


3: The first 4 grades (none – mild) are judged purely “cosmetic. In fact children and parents often judge the grades questionable – mild more highly than none. Research finds these milder forms of dental fluorosis often improve dental health related quality of life (Do and Spencer, 2007; Chankanka et al., 2010; Peres et al., 2009; Biazevic et al., 2008; Büchel et al., 2011; Michel-Crosato et al., 2005).

In contrast research shows that the moderate/severe grades of dental fluorosis have a negative impact on health-related quality of life(Chankanka et al., 2010; Do and Spencer, 2007; Chikte et al., 2001).

4: Anti-fluoride propagandists often lump all grades together – presenting dental fluorosis as always bad. It also enables them to produce high figures to inflate the apparent problem. That is deceptive.

5: Anti-fluoride propagandists often use data from countries like India and China where fluorosis is endemic in their arguments against CWF. The figure above shows this is also deceptive.

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Declan Waugh pushes another anti-fluoride myth


Declan Waugh – Champion cherry-picker

Declan Waugh seems a bit of a late developer. He has only just got around  to finding those papers that anti-fluoride propagandists like to cite as evidence that oral health does not decline when community water fluoridation is stopped. Of course, he cherry-picks the appropriate papers and is then careful not to give the full evidence.

But he has whipped up a Letter to the Editor promoting his new “discovery” – and encourages his fans to use the same information for their own letters to the editor.

Here’s Waugh’s claim in his letter to the editor (which he encourages his fan’s to duplicate).

Dear Sir.

In recent decades in four seperate countries notably Finland, the Netherlands, Germany and Cuba dental health professionals warned of the grave dangers to public health from discontinuation of water fluoridation. Yet ironically peer reviewed published scientific research demonstrated that dental health significantly improved among children when fluoridation of water ended. Scientific evidence proved in every case that the views and opinions of profluoridationalists among dental health professionals were misguided and errorneous. So why are we still listening to them?

Yours sincerely

  • Seppa L, Karkkainen S, Hausen H. Caries frequency in permanent teeth before and after discontinuation of water fluoridation in Kuopio, Finland. Commuity Dent Oral Epidemiol 1998;26:256 – 262.
  • Seppa L, Karkkainen S, Hausen H. Caries trends 1992 – 1998 in two low-fluoride Finnish towns formerly with and without fluoridation. Caries Res 2000;346:462 – 468.
  • Künzel W, Fischer T. Caries prevalence after cessation of water fluoridation in La Salud, Cuba. Caries Res. 2000 Jan-Feb;341:20-5.
  • Künzel W, Fischer T, Lorenz R, Brühmann S. Decline of caries prevalence after the cessation of water fluoridation in the former East Germany. Community Dent Oral Epidemiol. 2000 Oct;285:382-9.
  • Kalsbeek H, Kwant GW, Groeneveld A, Dirks OB, van Eck AA, Theuns HM. Caries experience of 15-year-old children in The Netherlands after discontinuation of water fluoridation. Caries Res. 1993;273:201-5

What these papers really say

I refered to this little myth in my article What happens when fluoridation is stopped? and will briefly repeat the information these propagandists always omit here.

L. Seppä, S. Kärkkäinen, and H. Hausen,Caries Trends 1992–1998 in Two Low-Fluoride Finnish Towns Formerly with and without Fluoridation.” Caries Research 34, no. 6 (2000): 462–68. The abstract for this paper concluded:

“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.”

The authors commented further on this research in Seppa et al (2002). They found their “longitudinal approach did not reveal a lower caries occurrence in the fluoridated than in the low-fluoride reference community.” But commented:

“The main reason for the modest effect of water fluoridation in Finnish circumstances is probably the widespread use of other measures for caries prevention. The children have been exposed to such intense efforts to increase tooth resistance that the effect of water fluoridation does not show up any more. The results must not be extrapolated to countries with less intensive preventive dental care.”

W. Künzel and T. Fischer,Caries Prevalence after Cessation of Water Fluoridation in La Salud, Cuba.  Caries Research 34, no. 1 (2000): 20–25. Again this study found no increase in caries after stopping fluoridation but the authors suggested why:

“A possible explanation for this unexpected finding and for the good oral health status of the children in La Salud is the effect of the school mouthrinsing programme, which has involved fortnightly mouthrinses with 0.2% NaF solutions (i.e. 15 times/year) since 1990.”

W. Künzel, T. Fischer, R. Lorenz, and S. Brühmann,Decline of caries prevalence after the cessation of water fluoridation in the former East Germany Community Dentistry and Oral Epidemiology 28, no. 5 (2000): 382–89. These authors found no increase of caries in two German cities after fluoridation of water was stopped. But again the authors suggest why:

“The causes for the changed caries trend were seen on the one hand in improvements in attitudes towards oral health behaviour and, on the other hand, to the broader availability and application of preventive measures (F-salt, F-toothpastes, fissure sealants etc.).”

Kalsbeek, H., Kwant, G. W., Groeneveld, A., Dirks, B., van Eck, A. A. M. J., & Theuns, H. M. (1993). “Caries Experience of 15-Year-Old Children in The Netherlands after Discontinuation of Water Fluoridation. Caries Research, 27(3), 201–205. Tooth decay continued to decline after discontinutation of fluoridation in both the areas previously not fluoridated and fluoridated. But the authors say:

“The question as to whether water fluoridation would have had an additional effect if it had been continued (presuming the application of existing preventive measures) cannot be answered, as there are no remaining communities with fluoridated water in The Netherlands.”

Tooth decay is complex because it involves several factors. Improvements in public health, especially dental health availability, and alternative fluoridation options have produced a general improvement irrespective of the availability of community water fluoridation (CWF). However, where comparisons are made between fluoridated and unfluoridated areas in the absence of other differences the benefits are seen.

Studies do show increase in tooth decay when fluoridation stopped

Of course there are other studies which Declan Waugh and his anti-fluoride mates will refuse to cite because they do not support their claims. In Fluoride debate: Ken Perrott’s closing response to Paul Connett? I discussed a paper which did show an increase in tooth decay –  Attwood and Blinkhorn (1991), Dental health in schoolchildren 5 years after water fluoridation ceased in South-west Scotland.”  They measured dmft and DMFT – decayed, missing and filled teeth in primary and permanent teeth respectively.

The figures below illustrate the data from this paper which compared changes in oral health of two Scottish towns  in both 1980 and 1988. One town, Annan, had never had fluoridated water while the other, Stranraer, had it until 1983. This enabled the effects of both cessation of fluoridation and the generally observed improvement in oral health due to other factors to be compared and considered. The graphics show the results for 5 year old and 10 year old children.

Decayed missing and filled deciduous teeth for 5 year olds. Stranraer fluoridated until 1983. Annan not fluoridated.

Decayed missing and filled teeth for 10 year olds. Stranraer fluoridated until 1983. Annan not fluoridated.

The plots indicate aspects of the complexity of these sort of studies. Because 2 neighbouring towns were compared it was possible to measure the decline in oral health after discontinuation of fluoridation against a background of the general improvement in oral health, even in a non-fluoridated situation.

The moral here is don’t accept at face value the claims made by anti-fluoridation propagandists – even if they, like Declan Waugh, carry a self-endorsement of “scientist and fluoride researcher.”

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Severe dental fluorosis the real cause of IQ deficits?

A new study finds cognitive function defects, like IQ, in children are not significantly related to fluoride in drinking water. But they are associated with medium and severe dental fluorosis.

This interests me for two reasons:

  1. The report is by Choi and Grandjean who had also authored the 2012 meta-review often used by anti-fluoride activists to claim that community water fluoridation causes a lowering of IQ (the authors subsequently pointed out the high fluoride concentrations in the papers they reviewed meant that conclusion is not valid)
  2. The data reported is consistent with my suggestion in Confirmation blindness on the fluoride-IQ issue that reported relationships between IQ and drinking water fluoride concentration could really indicate a relationship with severe dental fluorosis, and not drinking water fluoride itself.

The new report is:

Choi, A. L., Zhang, Y., Sun, G., Bellinger, D., Wang, K., Yang, X. J., … Grandjean, P. (2014). Association of lifetime exposure to fluoride and cognitive functions in Chinese children: A pilot study. Neurotoxicology and Teratology.

Firstly – this is only a pilot study and has several acknowledged weaknesses – the small number of children studied (51) being the most obvious. However, this is what was found:

“Sixty percent of the subjects examined had moderate or severe fluorosis. These children were exposed to elevated fluoride concentrations in drinking water. Children with normal or questionable Dean Index were all from households with a water fluoride concentration of 1 mg/L and had urinary fluoride excretion levels below 1 mg/L.”

The children were placed in 3 groups according to their degree of dental fluorosis:

  1. Normal/questionable (N=8)
  2. Very mild/mild (N=9)
  3. Moderate/severe (N=26)

The high proportion of children with moderate/sever dental fluorosis indicates the study involved an area of endemic fluorosis.

And the results of neuropsychological tests:

“Results of multiple regression models show that moderate and severe fluorosis was significantly associated with lower total and backward digit span scores when compared to the reference combined categories of normal and questionable fluorosis (Table 4). Although the associations between fluoride in urine and in drinking water with digit span were not significant, they were in the anticipated direction. Motor coordination and dexterity were not significantly associated with fluoride in drinking water and fluorosis although higher levels were associated with poorer scores as well. Other outcomes did not reveal any association with the fluoride exposure.”

The authors used a number of neuropsychological tests. The digit span test results suggest a “deficit in working memory” for the children with moderate and severe dental fluorosis. None of the other tests used show any signficant relationship with indices for fluoride exposure.

So, this pilot study did not show any association of neuropsychological tests with fluoride concentration in drinking water but it did find an association with medium and severe dental fluorosis. This is consistent with my speculation in Confirmation blindness on the fluoride-IQ issue that “a physical defect like dental and skeletal fluorosis could lead to decreasing IQ.”

I argued that:

“minor physical anomalies are known to be associated with learning difficulties and emotional illness in children (seeHilsheimer & Kurko 1979). It seems entirely reasonable that a physical anomaly like severe dental fluorosis could lead to learning difficulties in children which could be seen as lower IQ values.”

There are many problems with the studies anti-fluoride activists promote relating IQ to fluoride in drinking water. But it could be that any real effect seen with the higher fluoride concentrations could simply be explained by effects of the physical anomaly of medium and severe dental fluorosis common at these higher concentrations.

Unfortunately the authors of this study still do not consider this possibility. I guess it could be that someone with a hammer only sees nails, and chemical toxicologists are only capable of considering brain damage caused by toxic chemicals. The effects of physical anomalies on learning difficulties are probably quite outside their training and experience.

Their confirmation bias and mental blockage on this meant they were considering dental fluorosis as just another indicator of dietary fluoride intake. However, even that assumption has its problems because genetic differences are also known to be involved in dental fluorosis.

I think this must be why they ended with a conclusion that could well be quite unfounded:

“This pilot study in a community with stable lifetime fluoride exposures supports the notion that fluoride in drinking water may produce developmental neurotoxicity”

Dental fluorosis and community water fluoridation

Fluorosis is endemic in many parts of China and the high prevalence of medium/severe dental fluorosis (60%) among the children in the Choi et al (2014) pilot study shows their situation is not at all similar to that in areas of New Zealand and USA using community water fluoridation (CWF).

The figures below give some context.

Here are examples of the different degrees of dental fluorosis.

The graph below shows the situation reported for New Zealand in the 2009 New Zealand Oral health Survey (see Our Oral Health). No severe and only 2% moderate dental fluorosis reported.

This figure (taken from Fluorosis Facts: A Guide for Health Professionals) shows the amount  of moderate and severe dental fluorosis in the US is also very small.

Perhaps we can now contrast the situation here, in areas where CWF is common, with the situation in China in areas with endemic fluorosis where these studies were undertaken. The figure below is a slide from a presentation by Xiang (2014) to Paul Connett’s recent anti-fluoride “get-together” (Xiang 2014). This is not the very mild dental fluorosis attributed to CWF.

(Anti-fluoride people also often single out the study of Xiang, et al (2003). Effect of fluoride in drinking water on children’s intelligence. Fluoride, 36(2), 84–94, because unlike the others it is more detailed.  Xiang’s team has studied areas where fluorosis is endemic.)


Anti-fluoride activists often promote the meta-review of Choi et al (2012) in their arguments against CWF. However, there are many problems with these studies including the fact reported IQ effects were associated with much higher drinking water fluoride concentrations than occurs with CWF.

The new study of Choi et al (2014) did not confirm any association of neuropsychiatric measurements with drinking water fluoride concentration. However, it did show association of negative neuropsychological effects with medium/severe dental fluorosis.

This is consistent with the physical anomaly of severe dental fluorosis being the real cause of IQ effects and not any direct chemical toxic effect.

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Declan Waugh claims it’s “clear as day”

Declan Waugh is an anti-fluoride propagandist who specialises in naively distorting scientific and medical information to “prove” community water fluoridation (CWF) is dangerous. A common tactic of his is to select, really cherry-pick, medical data to show the mortality or disease prevalence is greater in the Republic of Ireland – and other countries with CWF, than the rest of the world.

Similarly, he often cherry-picks data to “prove” a sudden increase in disease or deaths in Ireland after the introduction of CWF in the late 1960s. He has recently pulled this trick with Irish data for vascular diseases. It’s a simple (and naive) recipe. He has found data in a report and selected parts of it to fit his message – ignoring everything else and specifically discussion of the trends in the data by the specialists.

So he has produced this graph:


You can see the point he is trying to drive home – but lets look at all the data in that table Waugh used from the cited “50 years of Heart Disease in Ireland“:

Looking at all the data


Perhaps we should consider the death rate – deaths/100,000 to correct for changes in total population


Another factor is changes of coding and diagnostic criteria used for reporting causes of death and details of vascular disease. The report lists a number of changes occurring in the periods 1958-1967, 1968 – 1978 and 1979 – 1999. It also refers to “the lack of specification of diagnoses during the early years covered by this review.” What this means is that some of the changes, especially the apparently sudden changes, may represent nothing more than changes in diagnostic criteria.

Waugh also simplifies the date that fluoridation commenced in Ireland – claiming 1965. The Irish Forum on fluoridation 2002 reported that CWF started in Dublin in 1974, in Cork in 1965 and over the next 5 years in other areas. This suggests another reason to be careful about interpreting sudden changes in data during 1964 – 1970 as due solely to introduction of CWF.

So things are nowhere as simple as Declan Waugh presents it. Of course they never are. The intelligent reader should read the report and not just rely on cherry-picked data and motivated rationalisation resulting from confirmation bias.

A more rational understanding

The report itself  states that Ireland does have a high mortality rate from cardiovascular disease, particularly compared with Europe. The report says:

“One way or another, the data from the 1950’s and 1960’s point to an ongoing epidemic of heart disease in Ireland for at least half a century. This is evidenced by the fact that in 1950, 31% of all deaths were due to vascular diseases.”


“The low rates of IHD mortality in the 1950’s and 1960’s is almost certainly a reflection of difficulties encountered in accurately diagnosing cardiac conditions at that time. Thus, many IHD deaths may have been coded to the ‘catch all’ category of ‘Other Myocardial Degeneration’ (ICD 422).”

And the decline in death rates since 1985:

“is the consequence of a multifaceted approach to the problem. Specifically it has been suggested that a proportion of the decline, ranging from 25% to 50%, may be due to primary prevention. A proportion of the decline (40% to 50%) may be related to early intervention and treatment of acute cardiovascular events and a proportion is due to secondary prevention among those with established disease (13-16). Data from the WHO MONICA project in 37 countries further suggested that a proportion of the decline in mortality may be related to economic
success (17).”

Another complicating factor has been “changes in the demographic structure of the population.”

So there you go. One can understand these fluctuations in death rate from cardiovascular disease using the normal factors related to changes in diagnosis, diet and health care, and treatment of cardiovascular events. No need to drag in the “universal demon” of fluoride.

Only one example

This is only one example of the sort of tricks Declan Waugh uses in his reports. He pretends to be a “scientist and fluoride researcher” and this, together with extensive scientific citation and dogmatic claims does fool some people. It fooled the Hamilton City Council in their consideration of CWF last year (see When politicians and bureaucrats decide the science).

He is dishonest – but his tactics are difficult to counter. It takes far less effort to present a naively “sciency” looking lie than to reasearch and communicate the facts. As they say, a lie can get half way around the world before truth can get its boots on.


And that’s what Declan Waugh relies on. That is why he does not allow peer review of any of his reports. That is why he will not engage in an exchange with critics of his reports.

He knows he has critics. Just the other day on his Facebook page he moaned:

“There are some sick people out there in twitter land who joke about the graphics I produce. . . .they will present any possible excuse to try and discredit the association while point blankly refusing to even consider the biological mechanisms by which fluoride contributes to disease.”

Well, Declan, it is part of the scientific ethos to engage with your critics. Respond to their criticisms – show where and why you think they are wrong – or acknowledge your mistakes. You refuse to do that because you “point blankly” refuse to “even consider” the discussion and evidence of the experts who write the papers and reports you cherry pick from.

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Fluoridation – a racist conspiracy?

Political activists campaigning on health issues often resort to scaremongering. This can be dangerous – especially when their stories have no real basis but rely on selective and distorted information.

Paul Connett’s Fluoride Action Network (FAN) often resorts to this sort of scaremongering. Now they are launching a series of stories dressed up as “exposès.”  The first is aimed at African-Americans and claims the US  “federal government has known for five decades that blacks were even more susceptible than whites to serious damage from fluoride added to water supplies, but it urged local governments to fluoridate the population anyway.”

Typically, Connett’s Crowd is promoting this campaign through FAN press releases which get picked up by “natural” health magazines and web pages. The articles are then heavily promoted throughout social media by activists – sometimes even making their way into the mass media (see Gov’t Failed to Warn about Fluoride’s Disproportionate Harm to Black Community and Feds: Blacks Suffer Most From Fluoride, Fluoridate Anyway).

The press release is summed up in the first paragraph:

“Government health authorities knew over 50 years ago that black Americans suffered greater harm from fluoridation, yet failed to warn the black community about their disproportionate risk, according to documents obtained by the Fluoride Action Network (FAN).”

So the evidence, the “document,” on which they hang this story, is a memo.


Now, that is very pathetic to hang a campaign on, isn’t it. And the campaigners are also relying on the false idea that anything obtained via freedom of information inquiry must have been “secret” or “hidden” from the public eyes. (Incidentally they do the same with the Certificates of Analysis for fluoridation chemicals used by water treatment plants – even appearing to think that listing an analytical result for contaminants, however small, is somehow “proof” that the contamination is a problem – see Fluoridation: emotionally misrepresenting contamination and Natural News comes out with a load of heavy metal rubbish on fluoride).

Differences in dental fluorosis prevalence not hidden

But the scientific information comparing prevalence of dental fluorosis among US whites and African-Americans is neither new or hidden. In fact, FAN’s press release does refer to a little of this published data, but again typically they distort it.

In particular it uses data from studies where fluoride in drinking water were often higher than the optimum levels for community water fluoridation (CWF). Consequently the studies include some people exhibiting the medium and severe forms of dental fluorosis never observed with CWF.

One of the papers cited is Martinez-Mier, E. A., & Soto-Rojas, A. E. (2010). Differences in exposure and biological markers of fluoride among White and African American children. Journal of Public Health Dentistry, 70(3), 234–40. It did report higher amounts of dental fluorosis in the African-American children they studied. But it also found that the African-American children in the study reported using larger amounts of toothpaste and had higher urine fluoride concentrations than white children. It concluded:

“Differences in fluoride exposure between two racial groups were observed. These differences are complex and need to be better defined.”

This does not warrant claims of  African-Americans being more susceptible than whites. Nor is the information “explosive” as the FAN press release claims.

Another study cited was Williams, J. E., & Zwemer, J. D. (1990). Community Water Fluoride Levels, Preschool Dietary Patterns, and the Occurrence of Fluoride Enamel Opacities. Journal of Public Health Dentistry, 50(4), 276–281. But the study actually doesn’t back up the FAN claims as these authors found:

“higher TSIF scores [an index of dental fluorosis prevalence] were associated with city children significantly more than with county children. There was no association of TSIF scores either in the city children or the county children with respect to gender, race, preschool dietary patterns, or dentifrice ingestion.”

Another cited paper is Butler, W. J., Segreto, V., & Collins, E. (1985). Prevalence of dental mottling in school-aged lifetime residents of 16 Texas communities.  American Journal of Public Health, 75(12), 1408–1412. These authors found “children who were White or had a Spanish surname had about the same prevalence of mottling while Blacks had a higher prevalence.” This appears to support the FAN claim but air conditioning in the children’s home and total dissolved solids and zinc in the drinking water also influenced prevalence of mottling. Significant mottling only occurred where  drinking water fluoride concentrations were over 2 ppm making the conclusions irrelevant to CWF where concentrations are usually in the range 0.7 to 1 ppm

Finally, they cite Beltrán-Aguilar, E. D. ., & Gooch, B. F. ; (n.d.). Surveillance for Dental Caries, Dental Sealants, Tooth Retention, Edentulism, and Enamel Fluorosis — United States, 1988–1994 and 1999–2002. Yes, this study did show African American had a slightly higher prevalence of very mild and mild dental fluorosis, as the figure below shows.


They did not advance an explanation for this but note that “different hypotheses have been proposed, including biologic susceptibility or greater fluoride intake.” One could also suggest differences in residential location – especially as some of the people in the study had moderate or severe dental fluorosis indicating they were likely consuming drinking water with a fluoride content above the level recommended for CWF.

But we could make the same comparisons with tooth decay data from this study (see figure below):


Perhaps we should be jumping up and down about the increased racial sensitivity of African-Americans and Mexican Americans to the disease of tooth decay and claim that this information has been suppressed or nothing done about the problem.

Or perhaps, as is most likely happening, authorities are just getting on with the job of working out how to deal with health inequalities in different ethnic groups.


This campaign is just another of the scaremongering attempts of Connett’s crowd. Appealing to conspiracy theorists it uses a memo obtained as part of a freedom of information inquiry to imply a cover-up. The campaing cites studies which do show real differences but do not show they result from differences in sensitivity. And they are not large enough to justify the extreme language of the press release and reports.

Of course there may be similarities in the dental health conditions of disadvantaged ethnic groups in the US, and in New Zealand and Australia, but the way some anti-fluoride propagandists have used these press releases to “prove” that NZ Maori and Australian Aborigine are adversely effected by CWF borders on naive racism.

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Fluoride debate: Second response to Rita Barnett-Rose – Daniel Ryan

Here is Daniel Ryan’s second response to Rita Barnett-Rose’s defence of here unpublished paper Compulsory water fluoridation: Justifiable public health benefit or human experimental research without informed consent“. That defence was posted yesterday at Fluoride debate: Response to Daniel Ryan’s critique – Rita Bartlett-Rose.

Daniel’s second response is available to download as a pdf.

Compulsory water fluoridation: second response to Rita Barnett-Rose

Dan Ryan 2

Daniel Ryan from the Making Sense of Fluoride group

Written by Daniel Ryan



This is my second response to Associate Professor Rita Barnett-Rose to her paper “Compulsory water fluoridation: justifiable public health benefit or human experimental research without informed consent”. It is a response to her document “RE: CWF Working Paper Article” (hereafter referred to as “Rita’s reply.”). I wish to thank Rita for acknowledging in that papers should be referenced accurately by using citations to the original sources rather than simply referencing activist sources. I am also pleased she is getting experts to review the science in her paper and am interested to know who the independent reviewers are.
In this this response I have collected a number of comments to consider under separate headings.

Objectively looking at the science.

Rita’s reply:

“…you object to my failure to include contrary studies that reaffirm the (English speaking countries’) public health agencies’/dental lobby positions on the safety and benefits of compulsory water fluoridation.”

“…with respect to your complaint or desire that I cite to contrary (i.e., pro-fluoridation) studies in addition to (or in lieu of) the published studies that I cite that tend to weigh against fluoridation”

“It is not meant to be an exhaustive examination of all studies on fluoridation and is specifically and accurately identified for what it is”

“…you are just as guilty of ‘cherry picking’ your sources and your studies as you suggest I am.”

“I am not interested in a battle of the studies debate”

“These reasons would remain even if compulsory water fluoridation were proven to be entirely safe, which it most definitely has not, despite the presumed “majority” view in the English speaking countries”

My reply:
Rita implies I only use ‘pro-fluoridation’ or ‘English speaking countries’ papers. This is incorrect – I cite papers which provide the best weight in regards to evidence. Science doesn’t take sides (good papers are neither “anti-fluoridation” nor “pro-fluoridation”, they present data and reasoning) and these are international. To clarify, my issue is not that Barnett-Rose (2014) was not using ‘pro-fluoridation’ papers, it was the quality of the studies themselves. Reviewers of the science should attempt to understand and evaluate the quality of the research.

I also look at the quality of journal. And I try to cite papers which are in high quality journals more as those journals attract the best scientific papers. Journals use a metric called “impact factor” that basically states how many times an average paper is cited by other papers. It is an independent, objective method to judge the quality of published research.
The hierarchy of scientific evidence in the literature is also important I illustrate this in the image below.

Secondary reviews published in peer-reviewed, high-impact journals and high quality randomised controlled trials with definitive results should be the preferred sources. For consideration of human health effects I consider that animal studies would be placed above “expert opinion” in this hierarchy.
Overall one needs to approach the literature intelligently and critically – considering the evidence provided in the individual papers and also considering other published material.

Instead I saw that Barnett-Rose (2014) did not evaluate the evidence well, only selecting evidence of harm in order to persuade the audience to accept her position. There is no reason to use low validity papers when there is plenty of high quality papers but unfortunately this happens when trying to “price” a preconceived idea.

An example of this is Barnett-Rose (2014) used an opinion article from the Scientific American many times as her source. This is not a scientific paper, it is not peer reviewed or in a research journal; furthermore the writer is not a scientist and definitely not an expert on the subject. This type of evidence would come below “expert opinion” on the image above. I hope such problems would be given as feedback from the independent reviewers.
Rita accuses me of cherry picking but fails to back this up. I do try to use only the best sources of evidence – usually systematic reviews. A systematic review is a literature review focused on a research question that tries to identify, appraise, select and synthesize all high quality research evidence relevant to that question.

The evidence shows

Rita’s reply:

“However, what I do believe is that the burden of proving safety and effectiveness lies with the pro-fluoridation side”

“It also appears to me that the pro-fluoridation side is playing “whack a mole” with the studies weighing against CWF – often trying to hammer down/marginalize the opposition each time a negative study pops up, rather than trying to consider the evidence objectively.”

“However, to me, if even one strong study exists, then the entire compulsory practice must be re-evaluated.”

My Reply:
The scientific consensus is that fluoridation works, it is safe and it is cost effective. We have evolved with fluoride and had it adjusted in our water for over 60 years in some countries. Developed countries where natural fluoride levels are low but choose not to use community water fluoridation (CWF) generally use other methods such as milk and salt fluoridation, which again are both safe and effective, or have very effective public health and dental systems. Over 5,500 papers have been systematically reviewed and no consistent association between fluoridation and illness has been found that has been confirmed through later research.

Using the latest evidence: Public Health England just released their water fluoridation review this month – Water fluoridation Health monitoring report for England 2014 and it concluded:

“This monitoring report provides evidence of lower dental caries rates in children living in fluoridated compared to non-fluoridated areas. Similarly, infant dental admission rates were substantially lower. There was no evidence of higher rates of the non-dental health indicators studied in fluoridated areas compared to non-fluoridated areas. Although the lower rates of kidney stones and bladder cancer found in fluoridated areas are of interest, the population-based, observational design of this report does not allow conclusions to be drawn regarding any causative or protective role of fluoride; similarly, the absence of any associations does not provide definitive evidence for a lack of a relationship.”

Last month a reviewHealth effects of water fluoridation: A review of the scientific evidence written on behalf of the Royal Society of New Zealand and the Office of the NZ Prime Minister’s Chief Science Advisor concluded:

“Councils with established CWF schemes in New Zealand can be confident that their continuation does not pose risks to public health, and promotes improved oral health in their communities, reducing health inequalities and saving on lifetime dental care costs for their citizens. Councils where CWF is not currently undertaken can confidently consider this as an appropriate public health measure, particularly those where the prevalence and severity of dental caries is high. A forthcoming study from the Ministry of Health is expected to provide further advice on how large a community needs to be before CWF is cost-effective (current indications point to all communities of 1000+ people). It is recommended that a review such as this one is repeated or updated every 10 years – or earlier if a large well-designed study is published that appears likely to have shifted the balance of health benefit vs health risk.”

Looking at the many other systematic reviews you will find a similar pattern. CWF is shown to be safe and effective. So the “burden of proof” really is on those claiming evidence of harm. They need to produce well supported and peer-reviewed studies which back up their claims.

If there is a strong evidence for health risks of fluoridation then I totally agree with Rita that it needs to be re-evaluated. Every year many studies are written on fluoridation and continued monitoring of the scientific findings occurs in many countries with the precautionary principle of being alert to any possible negative effects.

Health organisations

Rita’s reply:

“Please also note that any and all of your cites to the ADA lobby, or to the CDC (which, though its oral health division, works hand in hand with the ADA promoting fluoridation and thus has a serious conflict of interest/credibility problem) are unpersuasive to me – as they should be to anyone conducting even a minimum level of research into the history of and politics behind fluoridation (some of which is chronicled in my article, including the story of the EPA’s NTEU battle).”

“it does not take long to discover how politically motivated many “public health agencies” and “professional dental associations” are — or how willing they are to obscure, minimize, or bury contrary evidence or to marginalize the anti-fluoridation messengers, regardless of the evidence or the credentials of those messengers (e.g., Waldbott, Taylor, Marcus, Mullenix, Bassin, Hirzy).”

My reply:
I think Rita is placing her own bias on these judgments. One could equally say:

“It does not take long to discover how politically motivated Dr Paul Connett and FAN are — or how willing they are to obscure, misinform, or bury contrary evidence or to marginalise the pro-science messengers, regardless of the evidence or the credentials of those messengers.”

If Rita has a specific problem with the CDC or the ADA, I can use some of the many other hundreds of health organisations around the world. They all have similar conclusions about fluoridation. As I said in my first response, there is not one reputable health organisation that is against fluoridation. We already have Dr Paul Connett suggesting a massive conspiracy, I hope you do not agree with his accusations as this is generally the last resort for people who cannot find reasonable faults in the evidence but still refuse to believe it.

NRC Report

Rita’s reply:

“However, I believe that its review of fluoride toxicology is highly relevant to exposures from fluoridated water (and its exposure data itself suggests that some people drinking fluoridated water can, indeed, receive doses that can cause adverse health effects, including severe dental fluorosis and bone fractures).”

“In addition, in a number of health risk areas, the NRC panel concluded that there was not enough data, and/or that more research needed to be conducted, before definitive statements could be made with respect to other potential adverse health effects due to excess exposure to fluoride.”

My reply:
I will not repeat what I said in my earlier reply. The review itself said that it was not relevant to exposures to concentrations used for fluoridated water and to say it is “highly relevant” is spreading misinformation. The NRC report furthered shows the safety of fluoridation. As for the “more research needed”, that is always the case with science. That is why responsible public health agencies continue to monitor research findings.


Rita’s reply:

“I would genuinely be interested in knowing why you feel so strongly that imposing this practice on everyone is ethically justifiable.”

“Thus, I am very curious as to why there appears to be such an aggressive campaign on the pro fluoridation side to impose this practice on the world – and why anyone believes that personal liberties and rights to bodily integrity should be sacrificed for a public health practice addressing a non-contagious disease.”

“I would also be interested in understanding where you personally believe compulsory public health practices should begin and end (e.g., do you believe governments should mandate compulsory flu shots? What about the HPV vaccine that the Governor of Texas tried to mandate for girls? Where should the personal right to bodily integrity begin and end, in your opinion? And how comfortable are you with public health officials mandating what is good for you?…)”

My reply:
I don’t see how you conclude that I “feel so strongly that imposing this practice on everyone”. I, myself, could say I am strongly against misinformation. The MSoF society is here to help explain what the actual scientific evidence shows to the public, not to advocate for CWF at any cost. It is up to the communities if they want to use CWF and we, the MSoF Society, support their democratic right to decide.

But regarding ethical aspects, you might be interested in what the Nuffield Council on Bioethics decided. It:

  • Rejected the prohibition of water fluoridation based on the argument of mass medication and restricting personal rights.
  • Affirmed that water fluoridation should be accepted based on the quantified risks and benefits, the potential alternatives, and, where there are harms, the role of consent.

They also used a ‘stewardship mode’ to analyse the acceptable degree of state intervention to improve population health, concluding that water fluoridation can be justified based on its contribution to the goals of stewardship: the reduction of health inequalities, the reduction of ill health, and the concern for children, who represent a vulnerable group.

The New Zealand High Court this year ruled that fluoridation of the water supply:

  • is not a medical treatment,
  • does not violate the right to refuse medicine,
  • is not in breach of the Bill of Rights, And that
  • the Council was thoughtful and responsible in making their decision to begin fluoridation, and had no obligation to consider “controversial factual issues” (anti-fluoride propaganda).

You could say there is an aggressive campaign on both sides, but people are pushing for fluoridation simply because it works – reducing up to 40% of caries over a whole population.

Dental caries is a serious chronic disease, it makes no difference if it is contagious or not. The Royal Society Review pointed out that:

“…tooth decay (dental caries) remains the single most common chronic disease among New Zealanders of all ages, with consequences including pain, infection, impaired chewing ability, tooth loss, compromised appearance, and absence from work or school. Tooth decay is an irreversible disease; if untreated it is cumulative through the lifespan, such that individuals who are adversely affected early in life tend to have pervasive decay by adulthood, and are likely to suffer extensive tooth loss later in life. Prevention of tooth decay is essential from very early childhood through to old age”.

The Royal Society Review also suggested that removing fluoridation would have direct and indirect costs to society.

“Tooth decay is responsible for significant health loss (lost years of healthy life) in New Zealand. The ‘burden’ of the disease – its ‘cost’ in terms of lost years of healthy life – is equivalent to 3/4 that of prostate cancer, and 2/5 that of breast cancer in New Zealand. Tooth decay thus has substantial direct and indirect costs to society.”

I am all for protecting the vulnerable. If individuals do not consent, they can simply choose not to partake of the community water supply (bottled water, filters, rain water, etc.). I feel this is starting to head slightly off-topic but to answer your question, if the vaccine given out is safe and effective for the general public then I have no problems with compulsory shots for children. While choice is nice thing to have, you cannot always get it, especially if it is going to lower the quality of life in children.

The New Zealand High Court summarised some ethical aspects in the decision I referred to above:

“Provided it does not have consequences for public health a person has the right to make even the poorest decisions in respect of their own health. But where the state, either directly or through local government, employs public health interventions, the right is not engaged. Were it otherwise, the individual’s right to refuse would become the individual’s right to decide outcomes for others. It would give any person a right of veto over public health measures which it is not only the right but often the responsibility of local authorities to deliver.”

The World Health Organization

Rita’s reply:

“Data published by the WHO suggests that the decline in dental caries is similar in both fluoridated and unfluoridated countries, and I have heard of no massive outbreak of a worldwide dental carie epidemic that has been attributed to a lack of fluoridated water (rather than to poverty, poor nutrition, or a lack of access to proper dental care).”

My reply:
Petersen & Lennon (2004), a WHO funded study showed dental caries remain a major public health concern, affecting 60–90% of schoolchildren and the vast majority of adults. While fluoride is not a silver bullet, it is just part of the problem, it should not be ignored when it can clearly help very effectively. Their study goes into a number of suggestions for alleviating tooth decay, one being fluoridation.

“Water fluoridation, where technically feasible and culturally acceptable, has substantial advantages particularly for subgroups at high risk of caries. Alternatively, fluoridated salt, which retains consumer choice, can also be recommended. WHO is currently in the process of developing guidelines for milk fluoridation programs, based on experiences from community trials carried out in both developed and developing countries.”

As for the similar DMFT decline between fluoridated and unfluoridated countries Rita claims this needs to be considered critically. Fluoride occurs naturally everywhere and it is very hard to compare one country to others because of the many other contributing factors such as; history, culture, ethnic differences, as well as differences in health services, dental practice and assessments. The graphical evidence FAN promotes on their website and elsewhere they do not account for naturally occurring fluoride or other programs (fluoride vanish, mouth rinse programs, etc.) and different history and social practices. Their graphs also use only 2 data points for each country. There is no consideration of also changing fluoridation amounts over time and their graph is very confusing. It does not enable proper consideration of different DMFT declines in different countries. The stats show Denmark having the lowest DMFT and FAN marked them as not fluoridated, but they actually have high levels of naturally occurring fluoride.

If you look at the WHO data in more detail (graph left does this for the Irish Republic using the same WHO data) you will find that fluoridated areas show faster declines in DMFT than unfluoridated areas.

Making Sense of Fluoride

Rita’s reply:

“…you complain about FAN not being a legitimate source of credible scientific information, but your organization is also a political advocacy (pro-fluoridation) group”

“I urge you to conduct such a battle with a more appropriate sparring partner, such as FAN-NZ.”

My reply:
Like yourself, I am not a scientist – I am a software developer; my responses get checked by scientists but I would always look into the evidence in scientific studies. I avoid political or activist organisations (legitimate or not). The Making Sense of Fluoride society is not a pro-fluoridation group, we are a pro-science group. We will go with what the scientific consensus says and will spread warnings, if for example: some time in the future, CWF was really found to be harmful.

The objectives of the MSoF incorporated society are:

a) To foster awareness and dispel misinformation regarding fluoride with a focus on CWF.
b) Use the scientific method as the foundational platform upon which this awareness is promoted.

FANNZ, now known as Fluoride Free NZ (and a close partner of FAN), will always be anti-fluoride no matter what the evidence shows. For that reason it is usually not fruitful debating them. Their incorporated society main purposes make clear their opposition to CWF irrespective of the science:

a) To bring about the permanent end to public water fluoridation (“fluoridation”) in New Zealand.
b) To provide resources, both personal and material, to others opposing fluoridation in New Zealand.
c) To provide a central contact point for those opposing fluoridation in New Zealand.


Rita’s reply:

“This statement about “mounting scientific evidence” at the start of my paper (near fn. 2) actually references an entire section of my article – (“See discussion infra Sec. II-B”) — and not an opinion piece by Colquhoun, which is only referenced – appropriately – at footnote 65 (referring to “formerly avid fluoride proponents” who have changed their minds). I have no desire to engage with insincere zealots, so I hope that you simply made a mistake there.”

My reply:
I apologise for my mistaking you and any offense it may have caused you. It was clearly a simple mistake that anyone could have made and I had no intention to twist your words.

Wrapping up

Rita’s reply:

“After this exchange, however, I am only interested in a private discussion with you, which is something you may not be interested in as it may not advance your organization’s agenda”
“However, your Facebook posting has generated some contact to me by a few rude (and seemingly unbalanced) pro fluoridation folks”

My reply:
MSoF is always happy to have private discussions if you are willing to listen to our feedback. A lot of our work is outside of what the public sees but we always up for public exchanges to share to our followers.

You will find that your paper got sent all over Facebook and the media; because it was publicised in a press release from FAN. That is how I found out about it.
It is a pity you were subjected to insults because of that publicity. That said I was also hit with insults on Fluoride Free NZ Facebook pages because of my response to you. These insults are common and something I have gotten used too; in either case it is a shame that people feel it best to engage in debate in disrespectful ways. Fluoridation is an emotional topic for some – personally I do my best to stick with the science and keep my emotions out.

Thank you Rita for making time in reading our feedback and responding to us.

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Fluoride debate: Response to Daniel Ryan’s critique – Rita Bartlett-Rose

Rita F. Barnett

Rita Barnett-Rose, author of Compulsory water fluoridation: Justifiable public health benefit or human experimental research without informed consent” has replied to Daniel Ryan’s critique of her paper. Daniel’s critique was posted yesterday at Fluoride debate: A response to Rita Barnett-Rose – Daniel Ryan.

Rita’s reply is available to download as a pdf

RE: CWF Working Paper Article

Dear Daniel,
I have now had a chance to consider your comments to my draft article. In some respects, I am flattered that you have devoted so much time to an unpublished working paper, and I thank you for giving me some of your opinions. I absolutely want to make sure that I have cited to sources accurately and have not mischaracterized any particular study I reviewed. To that end, I have now engaged independent review of my article from several highly-qualified scientists/researchers with the specific request that they review my article for scientific accuracy. After I have received their comments, I will revise my draft accordingly.

Unfortunately (or fortunately for me), I did not find in your review any specific places where I actually mischaracterized any cited study. Instead, your primary points of contention seem to be twofold: (1) you object to my use of Fluoride Action Network’s (“FAN”) website as a cited source; and (2) you object to my failure to include contrary studies that reaffirm the (English-speaking countries’) public health agencies’/dental lobby positions on the safety and benefits of compulsory water fluoridation.

First, with respect to my reliance on FAN. Of the 209 footnote references in my article, I believe only 17 of them are cites to FAN. Of those 17 cites, I am citing to the FAN website primarily as an easy way to get to the primary source material (e.g., studies or newspaper articles from around the world). For example, in footnotes 85-87, I could have listed the primary source studies, but I have found that many of these studies are hard to get on the internet for those who do not have paid subscriptions to the various science databases. I myself had to order a number of the primary sources from my University intra-library loan system and felt that it would be better to simply provide a link so that the reader could see the names of the studies and determine for himself/herself how to get to those primary sources. Nevertheless, your point is well-taken that I should not give the appearance of relying upon an advocacy group (including yours), and I will review those 17 cites to see if I should instead cite to primary sources.

Second, with respect to your complaint or desire that I cite to contrary (i.e., pro-fluoridation) studies in addition to (or in lieu of) the published studies that I cite that tend to weigh against fluoridation, as I have already indicated to you on two occasions: I am not interested in a battle of the studies debate, and I urge you to conduct such a battle with a more appropriate sparring partner, such as FAN-NZ. Specifically: you complain about FAN not being a legitimate source of credible scientific information, but your organization is also a political advocacy (pro-fluoridation) group, and, from your critique, you are just as guilty of “cherry picking” your sources and your studies as you suggest I am. Moreover, and in stark contrast to you, the section of my article where the studies are discussed is specifically entitled: “Scientific Evidence Against Compulsory Water Fluoridation.” It is not meant to be an exhaustive examination of all studies on fluoridation and is specifically and accurately identified for what it is. I am well aware of many of the pro-fluoridation studies — as well as the criticisms of many of those studies (in terms of who funded them, flaws in methodology, conflicts of interest, etc.) by those opposed to fluoridation. I do not believe either side has definitively proved their case with respect to safety/benefits or lack thereof. However, what I do believe is that the burden of proving safety and effectiveness lies with the pro-fluoridation side, as it is your side that is insisting on imposing this “public health measure” on everyone else, even in the face of substantial objection and despite existing studies suggesting serious risks of harm. It also appears to me that the pro-fluoridation side is playing “whack a mole” with the studies weighing against CWF – often trying to hammer down/marginalize the opposition each time a negative study pops up, rather than trying to consider the evidence objectively. I note throughout your critique that you often refer to studies that weigh against fluoridation as “flawed” or “debatable” or as somehow lacking in proper control mechanisms – while studies that support fluoridation are “quality studies.” (p.8). You also minimize any existing evidence weighing against fluoridation by qualifying it: “there is no quality research” (p. 4) “there is no robust evidence” (p. 4), “there is no strong evidence” (p. 6). However, to me, if even one strong study exists, then the entire compulsory practice must be reevaluated.

Please also note that any and all of your cites to the ADA lobby, or to the CDC (which, though its oral health division, works hand in hand with the ADA promoting fluoridation and thus has a serious conflict of interest/credibility problem) are unpersuasive to me – as they should be to anyone conducting even a minimum level of research into the history of and politics behind fluoridation (some of which is chronicled in my article, including the story of the EPA’s NTEU battle). Incidentally, as someone who did not have a pony in this race before doing the actual research (i.e., I am not a long-time anti-fluoridation advocate), it does not take long to discover how politically motivated many “public health agencies” and “professional dental associations” are — or how willing they are to obscure, minimize, or bury contrary evidence or to marginalize the anti-fluoridation messengers, regardless of the evidence or the credentials of those messengers (e.g., Waldbott, Taylor, Marcus, Mullenix, Bassin, Hirzy).

With respect to the NRC Report, I agree with you that it did not specifically address compulsory water fluoridation. However, I believe that its review of fluoride toxicology is highly relevant to exposures from fluoridated water (and its exposure data itself suggests that some people drinking fluoridated water can, indeed, receive doses that can cause adverse health effects, including severe dental fluorosis and bone fractures). In addition, in a number of health risk areas, the NRC panel concluded that there was not enough data, and/or that more research needed to be conducted, before definitive statements could be made with respect to other potential adverse health effects due to excess exposure to fluoride. This is hardly a ringing endorsement of the safety of fluoride or fluoridation. Nor is the NRC Report irrelevant to the fluoridation debate.

I see no point in going through your critique page by page to point out various flaws in it, as mostly you seem to be trying to persuade me with contrary evidence rather than identifying any mischaracterizations of the studies I did cite. I will, however, point out that your opening accusation on p. 2 that my “paper starts off by saying there is mounting scientific evidence against fluoridation” and that I used an opinion piece by John Colquhoun as my “evidence” to support this statement is outrageously incorrect, and it almost prompted me not to respond to you at all, as I do not appreciate my words being twisted or my cites misused to inflate your argument. This statement about “mounting scientific evidence” at the start of my paper (near fn. 2) actually references an entire section of my article – (“See discussion infra Sec. II-B”) — and not an opinion piece by Colquhoun, which is only referenced – appropriately – at footnote 65 (referring to “formerly avid fluoride proponents” who have changed their minds). I have no desire to engage with insincere zealots, so I hope that you simply made a mistake there.

As I said to you privately, I am more than willing to revise my article where I have misstated any of the cited scientific evidence. However, I disagree with you that a discussion on the legal and ethical aspects of CWF would be “confusing” or “pointless” at this point and I would genuinely be interested in knowing why you feel so strongly that imposing this practice on everyone is ethically justifiable. Data published by the WHO suggests that the decline in dental caries is similar in both fluoridated and unfluoridated countries, and I have heard of no massive outbreak of a worldwide dental carie epidemic that has been attributed to a lack of fluoridated water (rather than to poverty, poor nutrition, or a lack of access to proper dental care). Thus, I am very curious as to why there appears to be such an aggressive campaign on the pro-fluoridation side to impose this practice on the world – and why anyone believes that personal liberties and rights to bodily integrity should be sacrificed for a public health practice addressing a non-contagious disease. I would also be interested in understanding where you personally believe compulsory public health practices should begin and end (e.g., do you believe governments should mandate compulsory flu shots? What about the HPV vaccine that the Governor of Texas tried to mandate for girls? Where should the personal right to bodily integrity begin and end, in your opinion? And how comfortable are you with public health officials mandating what is good for you? Do you contend that they haven’t been wrong on a public health issue before?).

As for me, I remain convinced that CWF is legally and ethically unjustifiable. My article sets forth my reasons, so I won’t repeat those arguments here. These reasons would remain even if compulsory water fluoridation were proven to be entirely safe, which it most definitely has not, despite the presumed “majority” view in the English speaking countries. You will also find many of my reasons articulated by dissenting justices in fluoridation cases over the last 60+ years, when presumably even less “science” was available to support their nevertheless valid legal/ethical objections to CWF. I include some of these cases and dissenting opinions in my article.

Daniel, I thank you for your (heretofore) civilized exchange with me and I do welcome your thoughts if you have any on the legal and ethical justifications of CWF. After this exchange, however, I am only interested in a private discussion with you, which is something you may not be interested in as it may not advance your organization’s agenda. However, your facebook posting has generated some contact to me by a few rude (and seemingly unbalanced) pro-fluoridation folks, and I have no interest in entertaining their rants (which certainly do nothing but convince me that the pro-fluoridation side has something to hide). In any event, I do thank you for reaching out and for your interest in my article. I hope to ensure that my final draft will address any legitimate criticisms/issues.

Daniel Ryan’s response to Rita’s reply will be posted tomorrow. See Fluoride debate: Second response to Rita Barnett-Rose – Daniel Ryan.

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Fluoride debate: A response to Rita Barnett-Rose – Daniel Ryan

Dan Ryan 2

Daniel Ryan from the Making Sense of Fluoride group

Daniel Ryan President of the Making Sense of Fluoride group responded to the scientific claims made in Rita Barnett-Rose’s unpublished paper Compulsory water fluoridation: Justifiable public health benefit or human experimental research without informed consent“.

That section of Rita’s paper was posted as the first article in this exchange yesterday at Fluoride debate: The scientific evidence against fluoridation – Rita F. Barnett.

Daniel’s critique is available to download as a pdf.

Compulsory water fluoridation: A response to Rita Barnett-Rose – Daniel Ryan


I have contacted Associate Professor Rita Barnett-Rose about her unpublished paper Compulsory water fluoridation: justifiable public health benefit or human experimental research without informed consent.”  It concluded that “The evidence continues to suggest that compulsory water fluoridation is no longer justifiable as a public health benefit” and “human rights burden and economic costs are not reasonable or justifiable”.

There were claims about the science which (presumably) are important for the legal/ethical conclusions. We at Making Sense of Fluoride (MSoF) felt there was misinformation on the science and a public exchange would be a good way to engage in a discussion of the claims – even withdrawing those claims if found wrong. We thank Rita for listening to us and hope that we find common ground even if it’s just in the science.


For the most part of this discussion I will stick to pages 13-19 with the header “Scientific Evidence against Compulsory Water Fluoridation” and breaking down into the sub-headers.

First off, looking at the sources used, there are many that are comments and articles from political activists rather than primary research sources. For example Fluoride Action Network is not a credible scientific organisation. This is not a good way of reviewing the scientific literature; in fact it is very poor practice. This is a fundamental problem with this paper.

The paper starts off saying there is mounting scientific evidence against fluoridation. The evidence used was an opinion piece from John Colquhoun. Dental Watch has a paper “Why We Have Not Changed Our Minds about the Safety and Efficacy of Water Fluoridation: A Response to John Colquhoun” that critiques his paper:

“His paper rehashed earlier criticisms of water fluoridation, using selective and highly biased citations of the scientific and non-scientific literature”.

Why I Am Now Officially Opposed to Adding Fluoride to Drinking Water” from Dr. Hardy Limeback and “Dr. William Hirzy Portland letter” are also opinion pieces. It is important to note that Dr. Hardy Limeback is a member of the Advisory Board of Paul Connett’s Fluoride Alert Network. Dr. William Hirzy works for Fluoride Action Network as a paid political lobbyist. “Mounting scientific evidence”- nothing could be further from the truth. There is not one reputable health organisation that is against fluoridation.

1: Dental Fluorosis

There is no argument that having too much fluoride when the teeth are forming will cause dental fluorosis but this isn’t the case for fluoridation. There is little difference in frequency and severity of fluorosis between non-fluoridated and fluoridated areas, something which Barnett-Rose (2014) seems to ignore. The CDC source given was looking at fluorosis as a whole and not at fluoridated vs non-fluoridated, but it states that “community water fluoridation programs were developed to add fluoride to drinking water to reach an optimal level for preventing tooth decay, while limiting the chance of developing dental fluorosis”. If there were any large differences in fluorosis then I would be all for another look into balancing the levels of fluoride in those areas. In fact health authorities in many countries continually monitor research findings for this very reason and that was the reason for the National Research Council (2006) review which did recommend reducing the primary MCL of 4 ppm.

Any increase in fluorosis due to CWF would be in the very mild to mild fluorosis range. The dental fluorosis about which they speak in Warren’s et al. (2009) “Iowa study” is overwhelmingly of the barely detectable nature. The 2009 New Zealand Oral health Survey found very little difference between fluoridated and non-fluoridated areas, in terms of the levels of mild to very mild fluorosis (which has no effect on appearance, form or function of teeth), as shown on the graph below. In fact, Lida & Kumar (2009) have demonstrated mildly fluorosed teeth to be more decay resistant.


The statement that fluorosis is “the first sign of fluoride toxicity” is debatable. What sign of which particular toxicity? Just because there might be other effects which have not yet been shown is not proof that there are other effects. It presumably has been a common feature of teeth through the centuries and is harmless.

The American Dental Association website says:

“Yes, it is safe to use fluoridated water to mix infant formula. If your baby is primarily fed infant formula, using fluoridated water might increase the chance for mild enamel fluorosis, but enamel fluorosis does not affect the health of your child or the health of your child’s teeth”.

The recommendation by health authorities that parents use unfluoridated water to make up formula is a peace-of-mind suggestion, not a firm recommendation. For example the CDC says:

“However, if your child is exclusively consuming infant formula reconstituted with fluoridated water, there may be an increased chance for mild dental fluorosis. To lessen this chance, parents can use low-fluoride bottled water some of the time to mix infant formula”.

For infants and children in their tooth-developing years of 0-8, the upper limit (UL) for fluoride is lower, but only due to a risk of development of mild dental fluorosis. That’s why the UL for daily fluoride jumps to 10mg/day after age 8, once the teeth are formed.

The rest of the “Dental Fluorosis” section in Barnett-Rose (2014) talks about moderate to severe dental fluorosis, which is not caused by community water fluoridation and so is pointless to discuss.

2: Skeletal Fluorosis and Bone Fractures

Again, there is no disagreement that chronic exposure to high levels of fluoride can cause skeletal fluorosis and increase the risk of bone fractures. But you don’t see these problems at levels of 0.7-1.2 ppm in community drinking water. The Institute of Medicine has established that the daily upper limit for fluoride intake from all sources, for adults, before adverse effects will occur, short or long-term, is 10 mg. There is no quality research to show skeletal fluorosis can develop at the levels of 0.7-1.2ppm. Even the source used in Barnett-Rose (2014) says “Crippling skeletal fluorosis may be produced by levels of 10-20 mg/day over 10-20 years”.

National Fluoridation Information Service has released a report this month on fluorosis and concluded:

“There are no known health risks associated with CWF in New Zealand, and no severe dental fluorosis, or skeletal fluorosis, has been found. While fluoride is incorporated into teeth and bones, there is no robust evidence of toxic accumulation of fluoride in other tissues in the body”. It also noted in its conclusion “As with many vitamins and minerals, such as iron, and vitamins A and D, fluoride intakes at high levels can be toxic. However, it is impossible to experience acute fluoride toxicity from drinking water optimally fluoridated at levels between 0.7 mg/L to 1.0 mg/L (MoH, 2009), and there is no evidence of skeletal fluorosis resulting from CWF in New Zealand. It makes sound clinical sense to ingest a substance at a level that achieves maximum benefit with minimal adverse effects (Bowen, 2002)”.

One needs to be careful of cherry picking scientific studies. When you look at all the data you will find bone fracture is not an issue. Vestergaard et al. (2007), in a meta-analysis that used 25 studies, came to the conclusion that “there was no effect on hip or spine fracture risk”. He also noted that “in subgroup analyses a low fluoride dose (< or =20 mg/day of fluoride equivalents) was associated with a significant reduction in fracture risk”. This showed that fluoridation can help bones when at the optimum fluoride levels.

Ingestion of some fluoride is necessary as the bioapatites in our body contain both fluoride and carbonate as normal, natural components. The incorporation of ions like fluoride into bioapatites can change their solubility product by several orders of magnitude according to Driessens (1973). Posner et al. (1963) attribute the improved stability of bone to “the isomorphous substitution of fluoride in the apatite structure”.

3. Pineal Gland and Endocrine Disruption Studies

Fluoride can accumulate in the pineal gland. Calcification of the pineal gland is caused by calcium, phosphate and old age. Because the bioapatites in calcified tissues are actively undergoing mineralisation and remineralisation they easily incorporate fluoride into their structure and this leads to higher concentration of fluoride in calcified tissues than in bones generally. No evidence of harm has been found.

There is no known link to hypothyroidism at the levels we get in water fluoridation. I’m not sure where the evidence for “The fluoride dose capable of reducing thyroid function is low – just 2 to 5 mg per day over several months” from Barnett-Rosie (2014). Her source, the Fluoride Action Network website, points to a study Galletti & Joyet (1958), which says:

“Our aim was to elucidate the inhibitory effect of chronic administration of fluoride upon thyroid function in cases of hyperthyroidism. It was demonstrated that such an action appears only occasionally among persons subjected to massive doses of this substance”.

The study was working with prolonged administration of a daily dose of 2-20 mg (on top of their diet). This was also a very small study of 15 people who suffered from hyperthyroidism. Galletti also noted that

“Despite the relatively large amounts administered (up to 20 mg. of F~ for one injection), neither immediate nor delayed toxic manifestations were observed”.

This demonstrates my point that primary sources should be used, and definitely not activist websites.

The ADA concludes on its fluoridation facts document:

“There is no scientific basis that shows fluoridated water has an adverse effect on the thyroid gland or its function”.

It also states:

“The researchers concluded that prolonged ingestion of fluoride at levels above optimal to prevent dental decay had no effect on thyroid gland size or function. This conclusion was consistent with earlier animal studies”

4. Cancer Studies

Bassin (2006) data presentation did not show how many cases and controls were included in each of the models; and fluoride exposures were estimated rather than measured directly. The authors commented that “Further research is required to confirm or refute this observation”. The NHMRC (2007) observed that:

“Shortcomings in their study mean the results should be interpreted with caution pending publication of the larger study results. Co-investigators of Bassin point out that they have not been able to replicate these findings in the broader Harvard study that included prospective cases from the same 11 hospitals”.

There is no demonstrable link between fluoride and cancer. The American Cancer Society says:

“The general consensus among the reviews done to date is that there is no strong evidence of a link between water fluoridation and cancer”.

The National Cancer Institute says:

“Fluoride in water helps to prevent and can even reverse tooth decay. More than 60 percent of the U.S. population has access to fluoridated water through public water supply systems. Many studies, in both humans and animals, have shown no association between fluoridated water and cancer risk”.

This is backed up by systematic reviews e.g. the York Review (2000) reported “No clear association between water fluoridation and osteosarcoma”. The National Research Council (2006) commented:

“Assessing fluoride as a risk factor for osteosarcoma is complicated by the rarity of the disease and that population is all generally exposed to some level of fluoride”.

SCHER (2010) reported:

“a possible link between fluoride in drinking water and osteosarcoma, but studies are equivocal. No evidence from animal studies to support the link, and thus fluoride cannot be classified as to its carcinogenicity”.

5. Lower IQ’s in Children

It is debatable that Mullenix et al. (1995) interpretation on the study was flawed, it doesn’t matter if it was in a “well-respected peer reviewed journal” or not. Plenty of well-respected journals have released poor papers. One such example was Wakefield’s (1998) claim of a link between vaccines and autism, published in The Lancet.

The study by Mullenix et al. (1995) was refuted by Ross & Daston (1995):

“In summary, much of the ambiguity in the interpretation of these results could have been avoided with information from two concurrent or historical control groups: 1) a group to define the behavioral signature resulting from long term adulteration of the drinking water, and 2) a group to define the behavioral signature of animals with hippocampal damage in this testing system. Such controls are an essential feature of test validation and experimental design. Novel behavioral chemicals of unknown toxicity are dosed, and all possible results interpreted as neurotoxicity. Instead, both positive and negative control materials should be evaluated, and the results linked with well-characterized functional and morphological indices of neurotoxicity.

We appreciate the opportunity to provide our interpretations of this study. We do not believe that the study by Mullenix et al. can be interpreted in any way as indicating the potential for NaF to be a neurotoxicant.”

On top of that, it is also debatable if plasma levels in rodents due to high levels of fluoride are equivalent to those in humans. The National Research Council (2006) discussed the contradictory data used for attempting to show a ratio between humans and rats for blood plasma levels and concluded:

“Dunipace et al. (1995) concluded that rats require about five times greater water concentrations than humans to reach the same plasma concentration. That factor appears uncertain, in part because the ratio can change with age or length of exposure. In addition, this approach compares water concentrations, not dose. Plasma levels can also vary considerably both between people and in the same person over time (Ekstrand 1978)”.

Choi (2012) described 27 studies found majority in obscure Chinese scientific journals. China is not artificially fluoridated and the studies used high levels of naturally occurring fluoride in the well water of various Chinese, Mongolian, and Iranian villages. The concentration of fluoride in these studies was as high as 11.5 ppm. By the admission of the Harvard researchers, these studies had key information missing, used questionable methodologies, and had inadequate controls for confounding factors. These studies were so seriously flawed that the lead researchers, Anna Choi, and Philippe Grandjean, were led to issue a statement in September of 2012. Anna Choi said:

“These results do not allow us to make any judgment regarding possible levels of risk at levels of exposure typical for water fluoridation in the U.S. On the other hand, neither can it be concluded that no risk is present“.

Broadbent et al. (2014) used data from the Dunedin Multidisciplinary Study, which is world-renowned for the quality of its data and rigour of its analysis, and found no significant differences in IQ by fluoride exposure, even before controlling for the other factors that might influence scores. It controlled for childhood factors associated with IQ variation, such as socio-economic status of parents, birth weight and breastfeeding, and secondary and tertiary educational achievement.

6: Benefits from Systemic Fluoride Intake?

For this section I’ll limit the discussion to the benefits of systemic and topical intake of fluoride.

Even if the primary role of fluoride was topical, water fluoridation has a beneficial effect and makes a good delivery system. Consumption of fluoridated food and water enables transfer of fluoride to saliva and biofilms on the teeth. This fluoride, together with calcium and phosphate on the saliva, reduces acid attack on the teeth and so helps prevent tooth decay. Because fluoride concentrations in saliva decrease within an hour or so after brushing, fluoridated water complements use of fluoridated toothpaste. Our teeth are in more regular contact with food and water than they are with toothpaste.

Buzalaf et al. (2011) reports:

“More than 60 years of intensive research attest to the safety and effectiveness of this measure to control caries. In this case, however, it should be emphasized that despite being classified as a ‘systemic’ method of fluoride delivery (as it involves ingestion of fluoride), the mechanism of action of fluoridated water to control caries is mainly through its topical contact with the teeth while in the oral cavity or when redistributed to the oral environment by means of saliva. Since fluoridated water is consumed many times a day, the high frequency of contact of fluoride present in the water with the tooth structure or intraoral fluoride reservoirs helps to explain why water fluoridation is so effective in controlling caries, despite having fluoride concentrations much lower than fluoride toothpastes, for example. This general concept can be applied to all methods of fluoride use traditionally classified as ‘systemic’. In the light of the current knowledge regarding the mechanisms by which fluoride control caries, this system of classification is in fact misleading”.

Featherstone (2000) also demonstrated that:

“The cariostatic effects of fluoride are, in part, related to the sustained presence of low concentrations of ionic fluoride in the oral environment, derived from foods and beverages, drinking water and fluoride-containing dental products such as toothpaste. Prolonged and slightly elevated low concentrations of fluoride in the saliva and plaque fluid decrease the rate of enamel demineralization and enhance the rate of remineralization”.

The main benefit is from topical application but systemic ingestion still plays a role. Buzalaf et al. (2011) also states that:

“Evidence also supports fluoride’s systemic mechanism of caries inhibition in pit and fissure surfaces of permanent first molars when it is incorporated into these teeth pre-eruptively”.

Quality studies continue to show fluoridation to be effective today. Newbrun (1989), Brunelle & Carlos (1990) and Griffin et al. (2007) have proven water fluoridation continues to be effective in reducing dental decay by 20-40%.

National Research Council Report:

I will touch on the National Research Council (2006) report as Rita has asked me to give my assessment and it is used throughout her paper. The 2006 NRC Committee was charged with evaluating the adequacy of the US EPA primary (4 ppm) and secondary (2 ppm) MCLs for fluoride to protect the public against adverse effects, it did not look at the benefits. The EPA’s guidelines are not recommendations about adding fluoride to drinking water to protect the public from dental caries. Guidelines for that purpose (0.7 – 1.2ppm) were established by the U.S. Public Health Service. It reported:

“this report does not evaluate nor make judgments about the benefits, safety, or efficacy of artificial water fluoridation. That practice is reviewed only in terms of being a source of exposure to fluoride”.

After the Committee looked at all relevant fluoride literature, it recommended that the EPA primary MCL for fluoride be lowered from 4.0 ppm. The stated reasons for this recommendation were the risk of severe dental fluorosis and bone fracture with chronic ingestion of water with a fluoride content of 4.0 ppm or greater. No other reasons. Had this Committee had any other concerns with fluoride at this level, it would have stated so and recommended accordingly. Additionally, this Committee made no recommendation to lower the EPA secondary MCL for fluoride, 2.0 ppm which water fluoridation at 0.7ppm is 1/3 of this value.

In March of 2013, Dr. John Doull, the internationally respected toxicologist who chaired the NRC committee, made the following statement:

“I do not believe there is any valid, scientific reason for fearing adverse health conditions from the consumption of water fluoridated at the optimal level.”

Final recommendation of this Committee showed nothing that doubt on the safety of fluoride at the recommended optimal level. It also has no bearing on water fluoridation so using the NRC report to as a reason to stop fluoridation would be misguided.


I have outlined major flaws of the science of this paper, with the major criticism being not using primary sources. There was no assessment of the quality of the evidence. One should start with secondary reviews published in peer-reviewed, high-impact journals, including meta-reviews, review articles, and Cochrane Collaboration reviews; otherwise, high quality clinical trial reports with fairly large number of subjects.

Any further discussions on the ethics or legal matters with fundamental flaws in the science would make any exchange confusing and pointless.

Rita Barnett-Rose’s response to Daniel Ryan’s critique will be posted tomorrow. See Fluoride debate: Response to Daniel Ryan’s critique – Rita Bartlett-Rose

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Fluoride debate: The scientific evidence against fluoridation – Rita F. Barnett

Recently an unpublished paper by Rita F. Barnett, an associated professor of Legal Research and Writing at Chapman University, was heavily promoted by Paul Connett’s Fluoride Action Network and associated social media groups. Although basically a legal paper it did have a comprehensive section on the scientific  aspects of fluoridation.

Rita F. Barnett

She argued that the science indicated that community water fluoridation was neither effective or safe and was criticised for that. One of her critics, Daniel Ryan from the Making Sense of Fluoride group, participated in an exchange with her about the science.

As this has only been available in downloadable pdf format I am posting this exchange over the next few days as part of the ongoing fluoridation debate.

This post today is the section from Rita Barnett’s paper in which she argues that the science does not support community water fluoridation.

Scientific evidence against compulsory water fluoridation

(extract from Compulsory water fluoridation: Justifiable public health benefit or human experimental research without informed consent by Rita F. Barnett.)

Fluoridation proponents have historically characterized those opposing or questioning fluoridation as “irrational, fanatical, unscientific, or fraudulent,” regardless of the legitimate scientific credentials of those opposing fluoridation.64 However, the mounting scientific evidence against fluoridation has begun to persuade an increasing number of scientific researchers and dental and medical professionals, and even some formerly avid fluoride proponents.65

While a comprehensive review of all existing and emerging toxicological, clinical and epidemiological studies weighing against fluoridation or urging further research is beyond the purview of this article, a brief discussion of some current areas of concern follows.

1: Dental Fluorosis

Dental fluorosis occurs when children absorb too much fluoride. This excess fluoride “causes the biochemical signal to go awry, thereby creating gaps in the crystalline enamel structure.”66 When the tooth finally erupts, is it unevenly colored, and may even be pitted and brown.67

Although early fluoride proponents claimed that mild dental fluorosis was the only potential, and relatively rare, negative side effect to systemic fluoride exposure, today about 30-40% of American teenagers show visible signs of dental fluorosis, with the rate as high as 70-80% in some fluoridated areas.68

Exposure to multiple sources of fluoride beyond fluoridated water supplies may partly explain the higher than expected rates of dental fluorosis, the first sign of fluoride toxicity. Indeed, it is nearly impossible today to avoid consuming fluoride even in non-fluoridated areas, since fluoride is now found in fluoridated toothpaste, the pesticide residue on fresh produce, processed food and beverages made with fluoridated water, and many pharmaceuticals.69 Yet, research from the Iowa Fluoride Study, the largest long-running investigation on the effects of fluoride, has indicated that the most important risk factor for dental fluorosis is exposure to fluoridated water.70 Perhaps for this reason, the American Dental Association now recommends that parents use non-fluoridated water for infant baby formula, while the Institute of Medicine recommends that babies only consume a miniscule 10 micrograms of fluoride daily, a near impossible feat when babies are fed infant formula reconstituted with fluoridated water – even where levels are within the “optimal” range of 0.7- 1 ppm.71

Despite the fact that dental fluorosis not only produces unattractive teeth but may also increase the risk of tooth loss, the EPA and other U.S. public health officials downgraded even moderate to severe dental fluorosis from an adverse health effect to a purely cosmetic one.72 This downgrade has been largely perceived as a bow to political pressure rather than a legitimate health risk assessment.73 In any event, “it is widely acknowledged that dental fluorosis is a manifestation of systemic toxicity,” leading to far more serious health risks than unattractive teeth alone.74

2: Skeletal Fluorosis and Bone Fractures

Fluoride, of course, is not equipped with a smart GPS, able to provide benefits to teeth while bypassing bone and other organs of the human body.75 Instead, approximately 93% of ingested fluoride is absorbed into the bloodstream, and while some of it is excreted, roughly 50% is deposited into bone, potentially leading to skeletal fluorosis.76 Skeletal fluorosis is characterized by painful and limited joint movement, spinal deformities, muscle wasting, and calcification of the ligaments.77 Numerous studies have already linked skeletal fluorosis to excess fluoride intake, and although health officials had formerly insisted that skeletal fluorosis would not develop unless a person ingested 20 milligrams of fluoride per day for over 10 years, current research now suggests that doses as low as 6 mg/day can cause early stages of the disease, and that skeletal fluorosis can develop even with fluoride levels as low at 0.7 to 1.5 ppm, the range used in many fluoridation schemes throughout the United States.78 Unfortunately, skeletal fluorosis may go undetected or misdiagnosed because some of the symptoms mimic symptoms of arthritis or other bone diseases, and because many doctors do not know how to diagnose it.79

In addition to skeletal fluorosis, epidemiological studies have now also linked high fluoride exposure to an increase in bone fractures, especially in vulnerable populations such as the elderly and diabetics.80 Related studies have shown that people once given fluoride to “cure” osteoporosis wound up having increased fracture rates.81

3: Pineal Gland and Endocrine Disruption Studies

Researchers have now discovered that an even greater amount of fluoride accumulates in the pineal gland than in teeth and bone.82 The pineal gland is responsible for the synthesis and secretion of the hormone melatonin, which regulates the body’s circadian rhythm cycle and puberty in females, and helps to protect the body from cell damage from free radicals.83 While it is not yet known if fluoride accumulation affects pineal gland function in humans, experiments have already found that fluoride reduced melatonin levels, interfered with sleep-wake cycles, and shortened the time to puberty in animals.84

In addition, studies have now shown that fluoride can contribute to hypothyroidism (an underactive thyroid), which is unsurprising, since fluoride was once used as a prescription drug to reduce thyroid gland function in patients with hyperthyroidism (an overactive thyroid).85 The fluoride dose capable of reducing thyroid function is low – just 2 to 5 mg per day over several months. This is well within the range of what individuals living in fluoridated communities are receiving on a regular basis.86

4: Cancer Studies

Numerous studies have now suggested a link between cancer and fluoride.87 However, perhaps even more disturbing than the evidence supporting the fluoride-cancer link is the evidence suggesting that political and other agendas have played a large part in the outright suppression of this evidence.88

First, in the early 1950’s, Dr. Alfred Taylor, a biochemist at the University of Texas, conducted a series of experiments in which cancer prone mice consuming water treated with sodium fluoride were found to have shorter lifespans than cancer-prone mice drinking non-fluoridated water.89 After discovering that his first round of tests had been contaminated because both groups of mice had eaten food containing fluoride, Dr. Taylor repeated the experiment, and found the same results – a shorter life span for the mice drinking the fluoridated water. However, because these damaging results appeared around the launch time of the early fluoridation schemes, and because public health officials had already come out in staunch support of fluoridation, Dr. Taylor’s work was misrepresented. Specifically, fluoridation proponents falsely claimed that Dr. Taylor had never conducted the second study revealing that the fluoride-cancer link was still present when the necessary controls were put in place.90

Then, in 1990, a study conducted by the U.S. government’s National Toxicology Program (“NTP”) found a positive relation for osteosarcoma (bone cancer) in male rats exposed to different amounts of fluoride in drinking water.91 When NTP downplayed the results in order to avoid a public outcry over compulsory fluoridation, a storm of controversy erupted, with a number of scientists outraged at the failure to report the cancer linked results accurately.92

Finally, in 2006, Elise Bassin and her colleagues at the Harvard School of Dental Medicine published a study in the peer-reviewed journal Cancer Causes and Control, which also showed a link between fluoridation and osteosarcoma in young men.93 Incredibly, Bassin’s own dissertation advisor at Harvard, Chester Douglass, wrote a commentary in the same journal warning readers to be “especially cautious” about Bassin’s results. This lead to yet another controversy, with Bassin’s defenders calling for an ethical investigation of Douglass, since, as it turned out, Douglass had some conflicts of interest and was the editor in chief of a newsletter for dentists funded by Colgate. 94

5: Lower IQ’s in Children

Researchers have also begun to focus on the damaging effects fluorides appear to have on the human brain. In the 1990’s, researcher Phyllis Mullenix studied the brain and behavioral effects of sodium fluoride on rats.95 Her study revealed that pre-natal exposure to fluoride correlated with life-long hyperactivity in young rats, while post-natal exposures often had the opposite, “couch potato” effect.96 Although Mullenix’s research was published in a well-respected peer reviewed journal, the fluoride proponents attacked her methodology and declared her results flawed.97 Since then, however, forty-six other studies have emerged showing a connection between excess exposure to fluoride and lowered IQ’s in children, with 39 of the 46 finding that elevated fluoride exposure is associated with decreased IQ, and 29 of the 31 animal studies showing that fluoride exposure impairs the learning and/or memory capacity of animals.98

In 2012, after conducting a meta-analysis of 27 of the fluoride-human IQ studies, conducted mostly in China, a team of scientists from Harvard’s School of Public Health and China’s Medical University in Shenyang concluded that the studies suggested an average IQ decrease of about seven points in children exposed to raised fluoride concentrations.99 In 2014, one of the chief authors of the initial 2012 meta-analysis, Harvard professor Philippe Grandjean, concluded in a follow-up article that “our very great concern is that children worldwide are being exposed to unrecognized toxic chemicals that are silently eroding intelligence,” and that fluoride’s effect on the young brain should now be a “high research priority.”100 Notably, a majority of the 27 studies analyzed were of water fluoride levels of less than 4 mg/L, which falls under the allowable concentrations of fluoride under current EPA regulations.101

6: Benefits from Systemic Fluoride Intake?

With so many current studies linking fluoride to serious health risks beyond dental fluorosis, the question remains whether fluoride’s public health benefits outweigh any and all of these risks. The Centers for Disease Control has deemed water fluoridation one of the “top ten health achievements of the 20th Century.”102 Proponents therefore insist that even if there are a number of recognized risks of fluoridation, there has been enough evidence to show that these risks are remote and are far outweighed by the benefits.103 Yet much of the available scientific data today suggests that any benefit from fluoride in terms of preventing tooth decay has been from topical application, rather than systemic ingestion.104 Moreover, even the benefits of topical fluoride treatments have been recently questioned, since most dental caries today are in the “pits and fissures” of the molars rather than on the flat surface of teeth, and various studies have now indicated that fluoride has no impact on the pits and fissures.105

Research conducted over the last twenty years has also shown that the estimated reduction in tooth decay due to compulsory water fluoridation has been grossly exaggerated. While at one time proponents boasted a 50-65% reduction in tooth decay, a great deal of current evidence suggests the real percentage is significantly lower, with some studies showing no measurable reduction at all. 106 Confounding claims of benefit even further, numerous studies have shown a substantially similar decline in the dental caries rate in countries that do not fluoridate, and in areas within the United States that remain unfluoridated.107

Nor have the asserted economic benefits of compulsory water fluoridation come to fruition. In fact, a number of economic evaluation studies have indicated that the costs of dental care may actually be higher in fluoridated communities than in non-fluoridated communities.108

Unfortunately, rather than considering the new data objectively, public health officials and dental lobbies spearheading fluoridation schemes often ignore, reject, or suppress the evidence that does not toe the pro-fluoride party line.109 Nevertheless, as evidence against fluoridation continues to 20 Compulsory Water Fluoridation [23 Sept 14 accumulate in a variety of health risk areas, two conclusions seem readily apparent. First, there remain significant unanswered questions about the risks and benefits of systemic fluoride, and further research before imposing or continuing fluoridation schemes seems not only scientifically prudent, but ethically necessary. Second, it is no longer acceptable for public health officials to simply dismiss the accruing negative data and to continue to insist that the levels of fluoride children and adults are receiving on a daily basis are without any serious health consequences. Fortunately, tentative moves by the EPA and other federal agencies suggest that at least some public health authorities are inching towards similar conclusions.


64 See e.g. Hileman, supra note 18, at 4. See also Graham, supra note 17, at 195 (noting a pro-fluoridation report characterizing fluoride opponents as follows: “The opposition stems from several sources, chiefly food faddists, cultists, chiropractors, misguided and misinformed persons who are ignorant of the scientific facts on the ingestion of water fluorides, and, strange as it may seem, even among a few uniformed physicians and dentists.”). See also Leila Barraza, Daniel G. Orenstein, Doug Campos- Outcalt, Denialism and Its Adverse Effect on Public Health, 53 JURIMETRICS J. 307, 307 (calling those who oppose fluoridation “denialists” who “misuse science to advocate positions that contradict the overwhelming weight of existing evidence”).

65 See e.g., John Colquhoun, Why I Changed My Mind About Water Fluoridation, 41 PERSPECTIVES IN BIOLOGY AND MEDICINE 1 (1997); Dr. Hardy Limeback, Why I Am Now Officially Opposed to Adding Fluoride to Drinking Water, FLUORIDE ACTION NETWORK (April 2000),; J. William Hirzy, Dr. William Hirzy, Former Head of EPA’s Headquarters Union Recommends Portland Flush Fluoridation Proposal (March 2013), FLUORIDE ACTION NETWORK,

66 Fagin, supra note 26, at 78.

67 Fagin, supra note 26, at 78; Hileman, supra note 18, at 9.

68 See Beltran-Aguilar, et. al., Prevalence and Severity of Dental Fluorosis in the United States, 1999-2004, NCHS DATA BRIEF NO. 53 (2010), See also Czajka, supra note 13, at 125.

69 Beltran-Aguilar, supra note 68; Peckham, supra note 13, at 165.

70 Fagin, supra note 26, at 79 (children exposed to fluoridated water were 50% more likely to have dental fluorosis than children living in non-fluoridated areas).

71 Peckham, supra note 13, at 165-66.

2 See Hileman, supra note 18 at 10.

73 Id.

74 Peckham, supra note 13, at 166.

75 Limeback, supra note 65 (“it is illogical to assume that tooth enamel is the only tissue affected by low daily doses of fluoride ingestion.”); Colquhoun, supra note 65 (“Common sense should tell us that if a poison circulating in a child’s body can damage the tooth-forming cells, then other harm also is likely.”).

76 Czajka, supra note 13 at 125.

77 Null, supra note 17, at 74.

78 Czajka, supra note 13, at 125.

79 Null, supra note 17, at 74; Hileman, supra note 18, at 13.

80 Fagin, supra note 26, at 79.

81 See Null, supra note 17, at 74-75.

82 Jennifer Luke, Fluoride Deposition in the Aged Human Pineal Gland, 35 CARIES RESEARCH 125-128 (2001). See also Czajka, supra note 13, at 126.

83 Fluoride Action Network, Pineal Gland, FLUORIDEALERT.ORG, (last visited June 25, 2014) (discussing/listing pineal gland studies).

84 Id.

85Fluoride Action Network, Thyroid, FLUORIDEALERT.ORG, (last visited June 25, 2014) (discussing/listing numerous thyroid studies).

86 Null, supra note 17, at 71. See also Fluoride Action Network, Endocrine, FLUORIDEALERT.ORG, visited June 25, 2014) (discussing/listing numerous endocrine system studies).

87 Fluoride Action Network, Cancer, FLUORIDEALERT.ORG, (last visited June 25, 2014) (discussing/listing numerous cancer studies).

88 See e.g., Null, supra note 17, at 77; Graham, supra note 17, at 229-240.

89 Null, supra note 17, at 77.

90 Id.

91 NTP Toxicology and Carcinogenesis Studies of Sodium Fluoride in F344/N Rats and B6C3F1 Mice (Drinking Water Studies), 393 NATL. TOXICOL. PROGRAM TECH REP SERV. 1-448 (1990).

92 Null, supra note 17, at 78-79.

93 E. B. Bassin et. al., Age Specific Fluoride Exposure in Drinking Water and Osteosarcoma, 17 CANCER CAUSES & CONTROL 421-28 (2006) (finding an association between fluoride exposure in drinking water during childhood and the incidence of osteosarcoma among males but not consistently among females). See also S Kharb et. al., Fluoride Levels and Osteosarcoma, 1 SOUTH ASIAN J. CANCER 76-77 (2012) (finding positive correlation between fluoride and osteosarcoma).

94 Fagin, supra note 26, at 80. 95 Phyllis J. Mullenix, Neurotoxicity of Sodium Fluoride in Rats, 17 NEUROTOXICOLOGY AND TERATOLOGY 169-177 (1995).

96Fagin, supra note 26, at 80. See also Null, supra note 17, at 74 (describing an ad campaign promoting a fluoridated spring water “for kids who can’t sit still.”).

97 Fagin, supra note 26, at 80.

98 Fluoride Action Network, Brain, FLUORIDEALERT.ORG, (last visited June 25, 2014) (discussing/listing numerous brain studies).

99 See Anna L. Choi et. al, Developmental Fluoride Neurotoxicity: A Systematic Review and Meta-Analysis, 120 ENVIRON. HEALTH PERSPECT. 1362-1368 (2012).

100 Philippe Grandjean & Philip Landrigan, Neurobehavioural Effects of Developmental Toxicity, 13 THE LANCET NEUROLOGY, 330-338 (2014) (“untested chemicals should not be presumed to be safe to brain development, and chemicals in existing use and all new chemicals must therefore be tested for developmental neurotoxicity.”). See also Diana Rocha-Amador, Decreased Intelligence in Children and Exposure to Fluoride and Arsenic in Drinking Water, Cad. Saude Publica, Rio de Janeiro, 23 Sup. S579-587 (2007).

101 See discussion infra Sec. III.

102 CDC FLUORIDATION, supra note 18.

103 Hileman, supra note 18, at 2.

104 See Czajka, supra note 13, at 127.

105 See e.g., Letter from Dr. Paul Connett to Scientific Committee on Health and Environmental Risks, the European Committee, at #7 (March 30, 2009), available at (“Since 1950, it has been found that fluorides do little to prevent pit and fissure tooth decay…This is significant because pit and fissure tooth decay represents up to 85% of the tooth decay experienced by children today.”).

106 Hileman, supra note 18, at 5.

107 Hileman, supra note 18, at 6-7. See also Michael Connett, Tooth Decay Trends in Fluoridated vs. Unfluoridated Countries (March 2012), FLUORIDEALERT.ORG, (noting that decay rates in non-fluoridated countries have declined at the same rate as those in fluoridated countries).

108 Hileman, supra note 18, at 7. 109 See e.g., Voices of Opposition Have Been Suppressed Since Early Days of  Fluoridation, CHEMICAL & ENGINEERING NEWS (August 1, 1988), available at

Daniel Ryan’s first response to Rita’s unpublished paper will be posted tomorrow – see Fluoride debate: A response to Rita Barnett-Rose – Daniel Ryan

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Another legal defeat for NZ anti-fluoridation activists

The NZ High Court has thrown out the appeal from an anti-fluoride group against the decision rejecting their request for a decision against community water fluoridation. The original case claimed that fluoridation violated human rights legislation and was beyond the legal power of councils. The rejected appeal claimed that fluoridation was prevented by the medicines act.

Latest in string of defeats

Justice Collin’s decision is just the latest in a string of defeats for the anti-fluoridation movement in New Zealand.

Earlier this year the Hamilton City Council reversed its previous decision to stop fluoridation. This came after a referendum held alongside the 2013 local body elections decisively supported fluoridation. Similar referenda in Hastings and Whakatane also supported fluoridation. The local bodies national conference this year resolved to ask that the fluoridation issue be taken out of councils’ hands and handed over to central government departments. This was also a recommendation from the Parliamentary Health Committee last year.

This current high court junction resulted from an appeal against the High Court 2013 rejection of action by the “natural health” industrial lobby group New Health NZ to prevent fluoridation In South Taranaki. And in August the Royal Society of NZ and the office of the Prime Minister’s Chief Science Advisor released a review of the scientific issues around fluoridation which supported its efficacy and safety. This review was partly commissioned by local bodies and will no doubt strengthen their resolve to resist future pressure from anti-fluoride activists.

All this means that the anti-fluoride organisations had lost much of their credibility with local body councils they formerly had. Serious moves to remove the issue from council consideration also weakens the activist strategy.

Fluoridated water not a medicine

In the current decision Justice Collin’s pointed out that in the Medicine Regulations 1984 “every reference to a medicine in this Schedule applies … only if the concentration of the medicine is greater than 10 milligrams per litre …”.  But, “when fluoride is added to domestic water supplies within the maximum allowable concentration of 1.5 mg/l the concentration of fluoride in domestic water supplies will be well below the concentration threshold required for fluoride to be a medicine in Schedule 1 of the Regulations.”

This “leads to the conclusion that the concentration threshold for fluoride in Schedule 1 of the  Regulations is so vastly higher than the maximum allowable concentration of fluoride in domestic water supplies that, when fluoride is added to domestic water at the authorised levels, it falls outside of the definition of “medicine” in the Act.” However, “fluoride would be a medicine under the Act if it was added to domestic water supplies in concentrations of 10 mg/l or more.”