This is the last, final, article in the Fluoride debate. There will be nothing more. It is Ken Perrott’s response to Paul Connett’s last article Fluoride debate: Paul Connett’s Closing statement.
For Paul Connett’s original article see – Fluoride debate Part 1: Connett.
“Skeptical scrutiny is the means, in both science and religion, by which deep thoughts can be winnowed from deep nonsense.”― Carl Sagan
Paul has used his right of reply and it really is time to close off this exchange.
I am not going to sieve through Paul’s long article and comment point by point – we are well past this. Instead I will discuss a basic issue central to the exchange (Paul’s reference to “weight of evidence analysis”) and show with several examples how superficial, and unscientific, Paul’s understanding of the approach is.
“Weight of evidence” – different things to different people
Weight of evidence can mean anything from a vague metaphorical description to a methodological approach or a theoretical/conceptual framework. Paul doesn’t clarify any further, but when he talks about balancing one set of studies or papers against another I find his concept very mechanical. It reminds me of the way the Hamilton City Council treated the submissions to last year’s hearings on the fluoridation issue (see my article When politicians and bureaucrats decide the science). Council staff reported:
“Of the 1,557 submissions received 1,385 (89%) seek Council to stop the practise of adding fluoride to the Hamilton water supply. 170 (10.9%) seek Council to continue the practise of adding fluoride and 2 (0.1%) submitters did not indicate a stance.”
Council, and Council staff, were impressed by these numbers – after all, place the submission printouts on a kitchen scales and of course the anti-brigade wins! Silly, I know, but this was one of the arguments staff supplied to council for ignoring the result of the referendum (where almost 70% supported fluoridation), at their November 2013 meeting. This extract from the draft resolution submitted by staff:
“All evidence has been considered carefully by Council and, while finely balanced, Council preference is to continue not to fluoridate the city water supply because: . . .
vi. Not fluoridating the city water supply reflects the majority of views expressed through the Council tribunal process.”
The silliness of such an approach is obvious when one starts to consider the quality and not the quantity of submissions. Here are a few examples from those opposing fluoridation:
Submission No 58:
I do not believe there is enough evidence to support the mass medication of our water supply’s for the good of all people. It is our right to choose to medicate ourselves with fluoride not the government right to force this medication I believe the fluoride in our water is toxic and needs to be stopped.
Water Fluoridation is medication ‐ even if the pro fluoridationist say it is not. Council does not have the right to medicate the water. Please STOP!
Submission No 61:
From what I have come to understand, Fluoride is a toxin that has been and will continue contribute to chronic long term health illnesses. Fluoride a toxic substance we don’t want in our water supply for our younger generation to be exposed to.
Submission No 65:
“I do not want N0 KEMICALS into my drinking water.Thank you very much,Dorel”
Submission No 975:
“There is no acceptable reasoning to mass dose the whole population. There is a significant amount of information describing the side effects of Fluridation of the water supply. If people want extra Fluoride then they can take tables. 90% + of the fluoride added to the town supply ends up in the environment. There are more than 100 pesticides manufactured from Fluoride.”
Submission No 237:
“I love New Zealand, it’s such a beautiful country. Fluoride is not necessary in the water supply. Please let people make their own choice about whether or not they want to ingest fluoride. It should not be forced upon anyone by adding it to the water supply. This is just plain and simply wrong!”
The local anti-fluoride activist organisation, the Fluoride Action MNetwork of NZ (FANNZ), promoted such meaningless submissions by proving a template form for their supporters. They were going for quantity and not quality – they are political activists, not scientists.
This shows why I reject the mechanical “weight of evidence” approach Paul often seems to be advocating. He certainly fights hard to avoid consideration of the quality of evidence he uses.
I can only agree with a “weight of evidence” approach if it is qualitative, not simply and mechanically quantitative. In fact, I would avoid the term and instead say our approach should be a balanced one, looking (as far as practicable) at all the evidence and considering it critically and intelligently.
Hence the quote from Carl Sagan at the head of this article.
I don’t think Paul does this. I show this in my comments and responses below.
From logical possibility to conspiracy
Paul’s book, The Case Against Fluoride, provides clear examples of a formula he uses to cast doubt on existing science, build up a library of claimed negative effects of fluoride in the human body and to suggest the scientific community conspires to suppress research findings and prevent important research from going ahead. It’s the sort of stuff ideologically driven opponents of fluoridation lap up enthusiastically. These tactics are not new – we have seen it all before with the creationists and the climate change deniers.
This formula has 3 steps:
1: Advance a claim with no real evidence. This can be done in several ways.
A): Establish a logical possibility. Paul uses a lot of “possibles,” “mays,” etc., in his book. No research evidence at all is required for this – just speculation and suggestion. For example:
“. . . if fluoridation were to increase the rates of hip fracture in the elderly, it would be serious and certainly grounds in itself to eliminate water fluoridation.” (p174).
“. . a possible mechanism exists whereby fluoride could bring about an excessive production of TSH from the pituitary. This may help explain why . . .” (p163).
“These speculations need to be investigated.” “Although more difficult to prove, it is reasonable to assume that many of the effects seen in vitro can occur in the whole body.” (p125)
“The bone is the principal site for fluoride accumulation within the body, and the rate of accumulation is increased during periods of rapid bone development as occurs in growth spurts during childhood. Thus, the cells in the bone are exposed to some of the highest fluoride concentrations in the body.” (p182)
This last speculation is fallacious as fluoride exists as a structural component of the solid bioapatites in the bone – not in solution – so the term “concentration” is misleading.
B): Use poor research evidence. He often uses the old trick of implying a cause from a correlation, or using research papers who have relied on this fallacy.
The graph below illustrates the fallacy. Most of us find the suggestion eating organic food is the cause of autism silly and we are not at all convinced – despite the excellent correlation. Maybe there are a few people who are so hostile to organic food that they take this suggestion seriously – we can see how their bias might lead them to claim this as evidence and even promote their story with such figures.
But replace the organic food sales with a vaccination statistic – we have a demographic who serious believe vaccinations are harmful and would easily lap up such a fallacious figure. (We are getting a bit close to the bone here – Paul’s Fluoride Action Network (FAN) is organisationally aligned with anti-vaccination (National Vaccine Information Center), anti-GM (Institute for Responsible Technology), and similar outfits through the Health Liberty Coalition.)
Now do the same with a fluoridation statistic and we are getting into very familiar territory. Think Declan Waugh and his graphs showing correlations between fluoridation and practically every illness known to humanity. In fact, Declan Waugh is doing this for autism on his Facebook page. Here is his graph.
Another approach is to just rely on poor quality research – selected to fit his desired conclusions. Consider Paul’s obsession with poor quality Chinese research papers showing a negative correlation of IQ and fluoride concentration in drinking water. These studies have problems with IQ measurement and confounding factors. How can one seriously claim causation when the studies don’t consider, for example, detailed analysis of education and family social conditions. Or other more important contaminants in the environment,
Paul sort of admits speculation or reliance on poor quality research but quickly leaves his admission behind in his eagerness to claim harmful effects:
“there are about twenty studies (albeit with questioned methodologies in some cases) suggesting potential damage to the brains of young children” (p156).”
“Although the validity of the scoring methods used for fractures is acknowledged by the authors to be questionable, this is a potentially important finding,” (p170)”
“At present there is no direct and unassailable proof that fluoridation per se harms anyone’s thyroid. This may be due to the paucity of studies conducted;” (p164)
“We emphasize that proof that fluoride acts on the thyroid in these ways in vivo is still lacking. Further research is needed, but, meanwhile, the mechanisms are plausible and based on existing science.” (p163).
“Although there is no direct evidence that fluoride can inactivate deiodinases, it is well known as an inhibitor of many enzymes, and the hormonal derangements reported in fluoride-exposed people have been interpreted in terms of effects on deiodinases.” (p162)
Paul builds his arguments on very flimsy foundations. He often admits as much but attempts to confound his readers with a fair bit of hand waving and Gish galloping.
2: Collect together any sources which can be interpreted to support the speculation. This may often need a bit of dredging – obscure journals or newsletters, comments recorded at meetings, foreign language sources, etc. Here a naive mechanical “weight of evidence” approach is useful as a pile of Byelorussian, Chinese, Indian, etc. papers from obscure or poor quality sources, often newsletters or reported statements and not scientific papers, weigh a hell of a lot more than one or two papers from reputable journals, by reputable research teams, who report contrary findings.
And of course the well-known problem of lack of reporting negative effects weighs in at zero.
Paul is very proud of the 80 pages of citations in his book. But many of them are repeated several time, are from sources not normally considered for scientific citation, or from sources difficult to track down. Very many of the citations are to his own activist FAN web site. A particularly disturbing aspect of the last sources (often used when referring to translation of foreign language material) is that very often the links lead nowhere. They have either been lost during web site reorganisation or may never have even existed. Who is to know?
3: Use the lack of reputable sources for his claims as evidence of a conspiracy. Paul can “double dip” with the “missing” research and publications from credible reasearch teams and journals. He records paucity of evidence from credible sources to support his own claims relying on poor quality sources, then implies the lack of material indicates at least an unwillingness to research problems or at worst a conspiracy not to do the research and/or hide the results. Of course such descriptors of unwillingness or conspiracy can also be turned on researchers or publications with contrary evidence. He can discount them by suggesting links with industry or personal bias – hence introducing a sort of negative quality to good research while refusing to allow judgement on the quality of the bad research.
“Most of the concerns about the immune system are largely speculative; once again the scarcity of literature on this reflects a lack of interest by governments that promote fluoridation. The same can be said about reproductive effects; despite an extensive literature indicating that, at high levels of exposure, effects of fluoride on the reproductive system have been observed in a wide range of animals and reptiles, very few human studies on the subject have been published or even undertaken.” (p197)
“The failure to explore the plausible connection between fluoridation and arthritis in any fluoridating country is difficult to understand. It is particularly surprising since the causes of most forms of arthritis (e.g., osteoarthritis) are unknown but are usually associated with the aging process. For those living in fluoridated communities the aging process will coincide with lifelong accumulation of fluoride in their bones and joints.” p170/171)
“We do not claim that these IQ studies add up to conclusive evidence that water fluoridation impairs cognitive development. . . . . it is wise to sit up and pay attention. The health authorities and governments of fluoridating countries show little sign of doing that.” (p156)
“A small minority of people, perhaps 1 percent, appear to be acutely sensitive to exposure to fluoride at the concentrations present in fluoridated water. The wide range of signs and symptoms resemble those seen in poisoning with larger amounts of fluoride. These findings date from the 1950s. However, far from leading to more extensive studies, they were ridiculed when introduced and have since been largely ignored.” (p136)
Fluoridation and IQ
Paul’s mechanical and selective understanding of “weight of evidence” sticks out like a sore thumb when he claims fluoride influences development of the child’s brain. Even though he notes the mainly Chinese studies he relies on had “questioned methodologies in some cases” (p156 of his book) this is perhaps his most favourite claim for rejecting fluoridation. In his last article he even spent some time developing a margin of error from the studies – rather previous, I think, as he had not established that the data he used was reliable or indicated causation
The European Scientific Committee on Health and Environmental Risks (2010) took a more intelligent and critical approach to the Chinese studies. This from their document Critical review of any new evidence on the hazard profile, health effects, and human exposure to fluoride and the fluoridating agents of drinking water:
“A series of studies on developmental effects of fluoride were carried out mostly in China. They consistently show an inverse relationship between fluoride concentration in drinking water and IQ in children. Most papers compared mean IQs of schoolchildren from communities exposed to different levels of fluoride, either from drinking water or from coal burning used as a domestic fuel. All these papers are of a rather simplistic methodological design, with no – or at best little – control for confounders, e.g., iodine or lead intake, nutritional status, housing condition, parent’s education level or income.”
This document concluded:
“Available human studies do not allow concluding firmly that fluoride intake hampers children’s neurodevelopment. A systematic evaluation of the human studies does not suggest a potential thyroid effect at realistic exposures to fluoride. The absence of thyroid effects in rodents after long-term fluoride administration and the much higher sensitivity of rodents to changes in thyroid related endocrinology as compared with humans do not support a role for fluoride induced thyroid perturbations in humans. Limited animal data cannot support the link between fluoride exposure and neurotoxicity,
noted in the epidemiological studies, at relevant non-toxic doses. SCHER agrees that there is not enough evidence to conclude that fluoride in drinking water may impair IQ.”
The NZ National Fluoridation Information Service (2013) also critically reviewed literature on this issue (see NFIS Advisory A review of recent literature on potential effects of CWF programmes on neurological development and IQ attainment).They concluded:
“The available evidence raises the possibility that high levels of fluoride in drinking water may have subtle effects on children’s IQ. However all of these studies have limitations in design and analysis, a clear dose-response relationship between DWFCs and assessed IQ are often not evident. The study authors are frequently very cautious in their comments, and several noted that any indicated negative effect applied only to high DWFCs. An hypothesis of fluoride neurotoxicity would also be supported by some experimental animal studies, however the great majority of these have only considered high fluoride intakes.
However collectively the data described are not robust enough to draw a firm conclusion that high fluoride levels in drinking water supplies contribute to retarded development of children’s brains. Also there is no clear evidence to suggest an adverse effect on IQ at lower fluoride intakes such as that likely to occur in New Zealand, where fluoridated water supplies contain fluoride in the 0.7 to 1.0 mg/L range.
Thus the balance of current scientific evidence does not suggest any risk for the development of full IQ potential for New Zealand Children from current community water fluoridation initiatives, where maximum DWFCs are 1 mg/L.”
Paul will respond that the studies were good enough to warrant further investigation but then he alleges that western researchers are either willfully ignoring these studies or even conspiring to suppress them and refuse to investigate further.
He never considers that, perhaps, the lack of better quality studies really is evidence of lack of effect – given the reluctance to publish studies with nil results.
Think about it, if there really was this effect from salt, milk or water fluoridation wouldn’t we be aware of it by now? After all, many countries do collect the sort of data about their populations, especially children, which would show any effect.
Maybe publication of the Choi et al (2012) meta-review will encourage more specialists to extract this data in their own countries and publish analyses. I personally know of one such study in New Zealand which shows no IQ effect of fluoridation. This study is of higher quality than the ones Paul relies on because the data was sufficiently extensive to allow consideration of confounding effects (eg. breastfeeding, education, income level, etc.). A paper has recently been submitted for publication so unfortunately I cannot offer a citation until it is “in press.”
Again, the importance Paul gives to a single study on fluoride and osteosarcoma illustrates his mechanical and selective approach to “weight of evidence.” He has not bothered including either the study by Comber et al (2011) of this issue in Ireland or the study by Levy & Leclerc (2012) for the US. Possibly because both of these concluded that water fluoridation has no influence on osteosarcoma incidence rates.
The NZ National Fluoridation Information Service (2013) briefly considered this literature and cancer incidence rates for New Zealand (see Community Water Fluoridation and Osteosarcoma – Evidence from Cancer Registries). Their conclusion:
“The analysis confirms that osteosarcoma is extremely rare in New Zealand with only 127 new cases registered during this period averaging 14.1 per year. The peak age is 10 to 19 years for both sexes. These rates indicate that there is no difference in the rates of osteosarcoma cases between areas with CWF and areas without CWF for both sexes, findings which are consistent with the two international studies.”
But, I guess, not consistent with the one study Paul relies on! A study Paul described as “unrefuted.” See what confirmation bias does to “weight of evidence?” Although his “unrefuted” strangely conflicts with his qualification about this research in his book:
“The evidence that fluoride causes osteosarcoma is not clear-cut. The studies of the relationships in both animals and humans are mixed.” (p 181)
Update: Here’s another paper published this moth which I guess Paul will studiously avoid. Blakey et al (2014). Is fluoride a risk factor for bone cancer? Small area analysis of osteosarcoma and Ewing sarcoma diagnosed among 0-49-year-olds in Great Britain, 1980-2005.
Breast feeding and the naturalistic fallacy
I understand Paul’s points about dose and dosage – they are not difficult concepts. Obviously they are important when we consider ingestion of fluoride and other environmental elements by infants. My reading indicates that those involved in health advice and regulation do consider dosage when discussing fluoride. I am at a loss to know why Paul thinks this issue is being avoided.
Paul keeps returning to the low level of fluoride in breast milk so I can’t help think he is still trapped by the naturalistic fallacy. He even links this to IQ claiming “whether by accident or by evolutionary “design” mother’s milk is protective against lowered IQ.”
Paul may make some mileage out of the naturalistic fallacy if he stays with fluoride, but bring in the other trace elements which present problems because of deficient levels in human breast milk and the fallacy has far less credibility.
A brief scan of the literature shows breast fed children are prone to some microelement deficiencies. For example, Kodama (2004) and Domellöf, et al (2004) report deficient levels of zinc, selenium and iron in breast milk. Supplementation of breast-fed infants with micronutrients, including fluoride, is sometimes recommended.
Paul’s treatment of this issue shows how simple his concept of “weight of evidence” is. He relies only on one-sided discussions by Colquhoun (1987), Colquhoun & Mann (1986), and Colquhoun & Wilson (1999). He seems not to have done anything to check the original papers from the project and relies on a single out-of-context letter from a bureaucrat which he interprets to his own satisfaction.
- Paul adamantly and publicly declares the Hastings fluoridation project a “fraud.” That is an extremely serious charge in the scientific community – scientific fraud is one of the worst accusations possible and usually leads to loss of career. It is unprofessional to make such a charge without being prepared to pursue it legally. I question the ethics of such an attack on people who are no longer here to speak in their own defense.
- Paul says:
“What convinces me the final report was a fraud was the authors did not mention the change in diagnosis when claiming the drop in tooth decay was due to fluoridation.”
Yet he does not reference the “final report” or show any indication he has checked this charge rather than take it on trust from his anti-fluoridation sources.
- He claimed in his second to last article that the decision to drop Napier as a control city was made for “bogus reasons” – yet gave absolutely no evidence to support such a serious claim. He now wants to avoid that responsibility by saying the issue (his claim) is a “red herring.” Sorry Paul, one should not avoid responsibilities – if you wish to make a serious allegation be prepared to back it up or withdraw and apologise – not run away from it.
I know from experience the complexity of long term trials involving many people doing different jobs. It is easy to take a bureaucratic letter out of context, oversimply or misinterpret problems of personal approaches to methodology and ignore the fact that managers of such trials inevitably face difficulties from factors outside their control. As for reporting findings, the data amassed and details of methodology and their changes can be mind-boggling for an outsider who attempts an understanding.
I will not pretend to have got my head around that project but here are a few observations:
- The findings from the trial were presented as scientific papers in the New Zealand Dental Journal (Ludwig and Ludwig, et al. 1958, 1959, 1962, 1963, 1965, 1971). The issues with Napier, originally proposed as a control, are discussed by Ludwig et al (1960), Ludwig & Healy (1962) and Healy et al (1962). Paul does not seem to have consulted any of these papers yet he considers his “weight of evidence” enough to make serious charges of “bogus” and “fraud!”
The authors did not trumpet their study “showed that fluoridation was a great success” – scientists are usually more circumspect. In this case conclusions were more along the lines “The results obtained in Hastings during a period of 75-78 month’s fluoridation are very similar to results obtained overseas after a comparable period of fluoridation.” (Ludwig 1962).
- The important data was reported in papers from 1958 – 1971. These are very brief but all include the statement that further information on methodology, data and statistical analysis is available to interested people. The details Paul’s seems to want may be in that unpublished “further information.”
- Colquhoun & Mann (1986) and Colquhoun & Wilson (1987) both quote from unpublished reports and communications where discussion of diagnostics and methodological changes occurred. Colquhoun and Mann even report that researchers believed evidence from the Napier data indicates these changes did not have an overriding effect. Even a simple glance at the published data shows that the decline in tooth decay was not restricted to the early period where diagnostic and methodological changes would have been expected to exert any effect. Compare the plots below.
Hastings data shows similar improvement in oral health even if project had started in 1957. Plots are for different ages.
I think Paul is irresponsible to make such damning charges of “fraud” without considering all the material. He actually has no evidence at all the project was a “fraud” or that the reasons for dropping Napier as a control were “bogus.” His behaviour is unprofessional.
The problems with longitudinal studies
There are inevitable problems with longitudinal trials of the sort which the Hastings Project eventually became. They are influenced by undetected confounding factors and hence can be difficult to interpret. This may not have been sufficiently recognised at the time and that may have coloured interpretation of the results.
But let’s not forget that much of the harsh criticism of fluoridation made by Colquhoun (1997) and Diesendorf (1986) rely on their own biased interpretation of such longitudinal trails. And today’s anti-fluoridation propagandists make the same mistake even though we now know better. Paul himself used the WHO data showing improvement in oral health in many countries in his first few articles to argue that fluoridation had no effect. He did not consider the multifactorial causes of that improvement or mention that where measurements made in single countries (like Ireland) clear differences between fluoridated and unfluoridated areas were seen.
Should we now accuse Paul of “fraud” because he made no mention of the full Irish data in his claim that the WHO data showed fluoridation ineffective?
Paul continually avoids systemic role of fluoride
He does this by stressing the surface mechanism initiating caries is “topical” and not “surface” and works hard to imply “topical application” methods are required. He has conceded to including the word “predominantly” when referring to the surface mechanism but seems not to understand the meaning of the word.
My dictionary definition for “predominant” is “Most common or conspicuous; main or prevalent.” The word does not mean “only” as Paul seems to assume.
Neither is tooth decay simply about the initiation of caries. It also involves the strength and hardness of the teeth where systemic fluoride plays a beneficial role – especially during teeth development in the pre-eruptive stage. Paul continually avoids this as he also does the normal and natural role of fluoride in bioapatites.
Paul has not even acknowledged the citations I have given supporting this systemic function for fluoride. I guess all I can do is add another one – published this month – Cho, et al (2014). Systemic effect of water fluoridation on dental caries prevalence.
I guess we should acknowledge there has been some progress during this exchange as Paul has made a few concessions. It is worth recording them here to show they have occurred – but of course I am interested to see if he still repeats his original claims elsewhere.
Fluoridated and unfluoridated data for the Irish Republic. Finally Paul seems to understand my point on this. At least he apologises and said he should have checked.
I really can’t understand why he was confused for so long (I raised is in my first article) but we all have our moments, I guess. He should now understand that use of WHO and similar data showing improvement of oral health in both fluoridated and unfluoridated areas is not a proof that fluoridation is ineffective. This fallacy is repeated again and again by opponents of fluoridation and ignores completely the multiple issues involve in oral health. Scientifically literate people should not resort to such fallacies.
I will be interested to see if he avoids this fallacy in future. A sign of good faith would be for him to remove or amend the section on the FAN website which promotes this fallacy.
Xiang et al’s margin of safety calculation. I asked Paul several times to clarify this because he was using a figure of 1.9 ppm yet Xiang’s paper was completely silent on how the value was obtained and seems to ignore the large variability of the data – another sign of poor reviewing by the journal Fluoride. Paul now seems to have walked away from reliance on Xiang et al (2003) and a threshold value of 1.9 ppm and wants to take a different approach.
But, he still wants to use the poor quality Chinese data and does nothing to justify using that data in the absence of demonstration of any causal, and not incidental, relationship between fluoride in drinking water and IQ. I think this makes his calculations meaningless.
In the meantime could he please remove the sections of his FAN website arguing for the 1.9 ppm margin of safety?
What happens when fluoridation is stopped. Paul has accepted my point that at least in the cases of the former DDR and La Salud, Cuba, the results are consistent with use of alternative fluoride sources such as fluoridated salt, mouth rinses and dental applications. While admitting I had a valid point he says:
“Ken responded that in two of these studies other measures were taken which might have explained why tooth decay did not increase. I in turn argued that that if this was the case it shows that there are alternatives to fluoridation that work.”
No one claims there are no alternatives to fluoridated drinking water. I have pointed out again and again that there are. So why the red herring? Paul was citing these studies to “prove” fluoridation is ineffective and I showed his conclusions were not justified.
Paul appears desperate to cling to any case I have not looked at. Must I go through every example and look at the details? Can he not do this himself? If there are no mitigating circumstances this would surely support the argument he wants to make. We should not do science this way. We should always approach the literature and research critically and intelligently.
Having conceded on La Salud and the former DDR is he prepared to modify his claims about these situations in his FAN website?
National Fluoridation Information Service
Some discussion of this body is important as Paul’s confusion extends a lot further than its name. He is demonstrating how he cynically uses terms like “weight of evidence analysis.” Cynical because he rejects the very body (NFIS) that is taking this scientific approach in New Zealand and throws his advocacy behind the body which is biased, uncritical and unintelligent in considering the evidence. The body which cherry-picks literature and interprets it selectivity to support its confirmation bias. He supports the NZ Fluoridation information Service (NZFIS).
As I wrote in my last article the NZFIS is an astroturf organisations set up by the FANNZ. Paul well knows that FANNZ has a clear bias and political aims with a declared purpose of “bringing about the permanent end to public water fluoridation (“fluoridation”) in New Zealand,” (quote from FANNZ rules).
Simple consideration of the NZFIS web site shows that it does no active work on the fluoridation issue. It’s material is old, biased and there is no current activity. However, the organisation is used for distributing biased press releases and attempting to claim scientific credibility. (See, for example, my recent article False balance and straw clutching on fluoridation.)
I can understand why Paul throws his support behind FANNZ and the NZFIS. They are part of the international tentacles of his organisation FAN. This is not about science or “weight of evidence analysis” at all. It’s about political activism.
So of course Paul must bad-mouth the organisation which is doing the work and taking a scientific approach in NZ – the National Fluoridation Information Service (NFIS). He says:
“My concern here is the use of taxpayer money (about 1 million dollars) to support the promotion of fluoridation rather than presenting a balanced view of the evidence.”
Well he would say that wouldn’t he? He treats public funding of NZFIS as a smear! That is the typical naive conspiracy theory approach taken by climate change deniers and any other anti-science organisation who attempt to discredit scientific findings. It distorts the facts completely – governments don’t employ scientists to produce a predetermined conclusion – if they wanted that theologians would be more appropriate and a lot cheaper. Research funding is not used to confirm a bias but to employ the people and resources who can answer important questions.
He also seems to think dropping a figure like “about 1 million dollars” acts as a smear. Let’s put this into context – here is the NFIS budget for 2012/2013. From the 2012-2013 annual plan.
And, no, the NFIS does not spend its time issuing misleading press releases or providing institutional status to political activists. Here is how an early evaluation document described its role:
“NFIS is an information and advisory service which will support District Health Boards and Territorial Local Authorities by providing robust and independent scientific and technical information, advice and critical commentary around water fluoridation.”
Go to the NFIS website and have a look at its output – it is professional and balanced. It is a laugh to even compare the barely operating astroturf NZFIS with it. Of course Paul wants to discredit the NFIS – he would like our scientists and health professional to rely on his own biased political organisations instead.
My criticism of FAN
Paul says that in making criticisms of FAN I am playing a “pro-fluoridation activist rather than a scientist.” I disagree because scientists must be concerned about the quality of material they consider. The must be aware of ideologically driven cherry-picking, opportunist use of selected research and the promulgation of unwarranted conclusions being promoted for political or ideological reasons. This is all part of looking at all the evidence critically and intelligently.
Scientists are concerned about poor quality and misinterpretation. It is disingenuous of Paul to make an accusation of activism to ignore or deny, the legitimacy of these concerns.
Paul claims that even if “FAN is a terrible organisation . . . That does not affect the scientific case for and against fluoridation.” I agree – the scientific case rests on objective reality and the science itself – not on reputation or rumour. But the determination and presentation of a case is very much influenced by the bias and the ideological and political positions of an organisation making the case.
In my last article I analysed the way that FAN worked to demonstrate why their information and claims are unreliable. I believe that was perfectly justified from a scientific perspective.
Similarly I think my arguments above analysing Paul’s mechanical interpretation of “weight of evidence,” and what he means by it in practice, are also justified from a scientific perspective.
Surely such analyses must be part of the critical and intelligent consideration of the arguments of organisations and people? Isn’t this what Carl Sagan meant with:
“Skeptical scrutiny is the means, in both science and religion, by which deep thoughts can be winnowed from deep nonsense.”
Several times I have stressed my motivations in this debate are scientific and not supporting a specific policy. I am concerned at the way the scientific literature and findings are being misrepresented by ideologically driven activists. We have seen this before on issues like evolutionary science and climate change. Similar misrepresentation is currently rife among advocates of alternative and natural medicine and health. I believe it must be opposed.
Hopefully many readers have taken my point on this. While I currently believe fluoridation of drinking water is a worthwhile social policy in New Zealand I don’t see it as the end of the world if it is rejected by a community. Nor do I see it as the only way of overcoming deficient levels of fluoride in our diet. And, of course, there is always the possibility that future research may change the current scientific consensus that fluoride at the levels used in water or salt fluoridation is safe and beneficial. Science is like that. Because our knowledge is always provisional, but improving over time, we sometimes do modify our conclusions.
So, if readers take my point about the need to overcome misrepresentation of science in these sorts of issues I will consider participation in this exchange worthwhile – even if most readers do not change their political views on support or opposition to fluoridation of water.
Balls, M., Amcoff, P., Bremer, S., Casati, S., Coecke, S., Clothier, R., … Zuang, V. (2006). The principles of weight of evidence validation of test methods and testing strategies. The report and recommendations of ECVAM workshop 58. Alternatives to laboratory animals : ATLA, 34(6), 603–20.
Blakey, K. et al (2014). Is fluoride a risk factor for bone cancer? Small area analysis of osteosarcoma and Ewing sarcoma diagnosed among 0-49-year-olds in Great Britain, 1980-2005. International Journal of Epidemiology, 2014, January 14.
Cho, H.-J., Jin, B.-H., Park, D.-Y., Jung, S.-H., Lee, H.-S., Paik, D.-I., & Bae, K.-H. (2014). Systemic effect of water fluoridation on dental caries prevalence. Community dentistry and oral epidemiology.
Choi, A. L., Sun, G., Zhang, Y., & Grandjean, P. (2012). Developmental fluoride neurotoxicity: A systematic review and meta-analysis. Environmental Health Perspectives, 120(10), 1362–1368.
Colquhoun, J. (1987). Education and fluoridation in New Zealand: an historical study. Ph.D. thesis. University of Auckland, New Zealand.
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The links to all the articles in the exchange are listed by date on the Fluoride Debate page. I will shortly put the articles together in a PDF document (and maybe an eBook format) so readers can download and consult at their leisure. Maybe we could even use Paul Connett’s speaking tour of New Zealand early in the year to encourage people to read the exchange.
Thanks to Paul Connett for agreeing to this exchange (it was actually his idea to try it as an on-line exercise) and to all the people who participated in the comments discussion.