NZ Fluoridation review – HS Micklen responds to critique

By Ken Perrott 17/02/2015


I have posted several articles in a series critiquing contributions to the Fluoride Free NZ report Scientific and Critical Analysis of the 2014 New Zealand Fluoridation Report which is aimed at discrediting the recent review Health Effects of Water Fluoridation: a Review of the Scientific Evidence produced by the Royal Society of NZ together with the Office of the Prime Minister’s Chief Science Advisor. The articles in this series are collected into a pdf document which can be downloads from Download report analysing anti-fluoride attacks on NZ Fluoridation Review.

In an attempt to encourage a discussion on the fluoridation review and the FFNZ report I offered all the authors and “peer-reviewers” of the FFNZ report the right of reply to my critiques. So far Dr H. S. Micklen (whose article I critiqued in Fluoride Free NZ report disingenuous – conclusion), is the only one to take up this offer.

Here is his reply. 


I thank Dr Perrott for reproducing my notes on the NZ Fluoridation Review and appreciate his comments. My appreciation would be warmer had he spent less time using his imagination and paid more attention to what I actually wrote.  He has me bustling around, agenda in hand, clutching at straws here, raising bogeys there, scaremongering, relying on this, calling for that, and getting confused about different grades of fluorosis (as if..,). All nonsense.  If I “distort the science” as Perrott’s headline proclaims, he does a great job of distorting the distortion.

Most of my short piece merely commented on a few places where, in my opinion, the NZ report failed – through error, omission or incompetence – to reach proper standards of objectivity and impartiality and exhibited ill-founded complacency. Since the NZ report was highly biased in favour of fluoridation, any criticisms of it are likely to have an anti-F flavour. Too bad; I was dealing with the report’s view of the science, not pushing my own. I avoided speculating on the outcome of issues that I consider unresolved, dental fluorosis (where Perrott makes nonsense of what I wrote) being the only exception.

Most of these issues have been argued over ad nauseam and I shall not try to unscramble Perrott’s lucubrations. The question of chronic kidney disease and its possible cardiovascular consequences is perhaps an exception. I gave credit to the Review for discussing the paper by Martin-Pardillos. Agreeing with the Review’s opinion that the results needed to be confirmed, I remarked “The interesting question is, what should happen meanwhile?” That is not a rhetorical question. What does, or should, happen when an alarm bell sounds over a long-established procedure? Does further research on the topic receive any funding priority, for example?  Perrott uses a piece of grammatical legerdemain to pretend that I called for CKD sufferers to be warned to avoid tap water, which I did not. In fact, I am inclined to agree with him that that might be extreme in the present state of knowledge. Perhaps it would be embarrassing, too, for a government to insist on putting fluoride in the water and then advise a substantial number of people not to drink it – or so one might think. But Perrott concludes “Any patients who are particularly worried can then take steps like using filtered water for their own peace of mind. This seems more appropriate than denying the rest of the population access to a simple, effective and safe (for them at least) social health policy like CWF.”  So that’s all right then, thanks to the patients, whom Perrott doubtless consulted, being willing to promote the alleged greater good. He has pricked a hole in the old mantra, though: “effective and safe – for some”.

Perrott asked for my feedback on his idea about the possible effect of dental fluorosis on IQ.  Since then his paper has appeared online as a short article in Neurotoxicology and Teratology. Perhaps the best thing I can do at this stage is pretend that it had arrived on my desk for peer review. I would have commented as follows.

“This communication refers to a recent paper by Choi et al (2014) that reports certain cognitive defects in young children affected by moderate-severe dental fluorosis. Choi et al suggest that this is due to an adverse effect of fluoride on the developing brain. The present author proposes an alternative explanation, namely that fluorosis itself, and the stress of living with it, can affect learning and general quality of life and result in poor performance in certain types of cognitive test. This appears to be a novel idea and, as such, is suitable in principle for publication as a short communication. There is, however, a fundamental question that the author should be invited to address and clarify with a view to possible resubmission.

“The paper is somewhat discursive and lacking in focus and in the course of it the author seems to lose track of what age group he is talking about. Surprisingly, he does not mention the age of Choi’s (2014) subjects, which averaged 7 years  (range 6-8). When he finally presents evidence that moderate-severe fluorosis is aesthetically displeasing and likely to impair quality of life, all of it relates to older children, mainly teenagers, who have reached an age to be self-conscious about their appearance and have been living with fluorosis for several years. In contrast, 16% of Choi’s (2014) subjects had no erupted permanent teeth at all and in the remainder eruption of the first permanent teeth would have been very recent. Since fluorosis was common in the community, having the condition would not appear abnormal. The crucial question is whether the author is proposing that the quality of life of these young children is so compromised by fluorosis as to impair their performance in cognitive tests. Apparently the answer is a tentative affirmative: It is just possible that the negative quality of life associated with oral defects like severe dental fluorosis contribute to cognitive deficits reported by Choi et al. (2012, 2014)’

“The author needs to discuss this issue in a transparent fashion so that readers can judge for themselves whether the proposal is plausible. Conversely, if he is not making such a proposal, that too should be made clear.

“The author might wish to refresh his memory of the paper by Hilsheimer and Kurko (1979), which really is of virtually no relevance to his argument.”

I hope this helps.

H S M 12 February 2015

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