This 2nd edition of the British Fluoridation Society-drafted fluoridation document is produced from the same standpoint as its 1994/95 predecessor, and with much the same one-sided approach. It is rather more substantial and heavily referenced than the 1st edition.
Like many other documents on water fluoridation it is propaganda dressed up as science. Because much of it pretends to the latter it is plausible, and may well persuade many who do not know where to look for the truth. It is curious that it has the Chief Dental Officer’s “full endorsement”, given his stated intention to set up a high-quality research programme to plug the gaps in the evidence.
Its flaws are mainly these:
- It is selective throughout. Nothing that casts doubt on water fluoridation is included, and assurances are mostly absolute. (Some examples: studies that support the dental case are claimed to have been wrongly rejected by the York review, e.g. Hoover (p. 30) that York rated inferior to Yiamouyiannis who found the opposite, while opponents’ studies are claimed to be flawed (e.g. Down’s, p. 32 col. 2); York’s favourable findings on bone fracture > 10 years are cited (p. 29 col. 1), but not their negative ones <10 years*; countries or areas that reject fluoridation, and there are many, are glossed over or not mentioned (p. 72); the later Medical Research Council report is preferred over York (passim); only ethicists and lawyers who support fluoridation are cited (pp. 88-92).)
- Assessment of the quality of evidence plays no part. The chief example is over the York report, whose pre-eminence as a systematic scientific review is not explained, but which is treated as just another review with less column inches than several other sources, notably the MRC which is preferred because of its dentally-orientated angle. As with the MRC report, One in a Million is a vehicle for importing preferred studies which York rejected on scientific grounds (e.g. pp. 7, 9, 21). There is long discussion of a non-peer-reviewed theoretical paper on the chemistry of bioavailability (pp. 42ff.), which is surely now water under the bridge after the Newcastle study (see below). There are 8 pages of raw league tables (pp. 13-20), which have no scientific standing. (Some other examples: Riley, Lennon et al. occupies a whole page (pp. 5-6, 21) on inequalities in dental health; it was the least reliable study – level C, 0.8/8 – in all the York review. Hoover et al. has a whole page in the cancer section (pp. 30-1 & 33: York scored it 3rd from bottom at 3.3), presumably because it yields the result the authors desire; and Hillier et al. (pp. 28 col. 2 & 33), another weak study, is similarly referenced in the bone section. York’s finding on cosmetically significant fluorosis based on over 70 studies is watered down by one study which the York reviewers would have known about but rejected (p. 24 col. 2).) The authors of One in a Million do not appear concerned about good evidence.
- The tone is often emotive. Fluoridators’ language abounds, with reiteration of “optimal” concentrations (these have not been scientifically demonstrated), of areas whose fluoride content is “adjusted” (i.e. raised by x 10 or more) so that populations can be “targeted” (i.e. whole regions fluoridated), and of communities who “enjoy” the “benefits” of fluoridation. The “400 million worldwide” who “benefit” are frequently emphasised, while the reader is reminded that it has been around for nearly 60 years, commanding universal professional support. There are photographs of decayed teeth and operations, and of smiling people serving no clear purpose other than subliminally to underscore the case being made.
- There are errors. Not all references support their arguments (e.g. Marinho  on pp. 4 col. 2 & 21, a reviewer who also has important things to say about the scarcity of safety evidence for all fluorides). York is said to have “found”, “demonstrated” and “concluded” many things (e.g. pp. 4-5), and this constant overstatement of findings and omission of caveats (e.g. p. 6 col. 2) runs throughout the document to give a spurious aura of certainty. It is stated more than once that York and others found “no evidence” of adverse effects (e.g. p. 27 col. 2), a careless if not dishonest use of terms. York is said to have “included 33 studies” on possible adverse effects (p. 28 col.1), whereas the true figure was 88 since the cancer and bone studies were missed. Fluoridation is said to reduce decay “very effectively and . . very safely” (p. 27 col. 1), a claim that the NHS CRD (‘York’) website cited in 12. below is at pains to dispel for the benefit of those who have not studied the York report. “Numerous searching reviews of the safety of fluoridation” (p. 28 col. 1) would be hard to find, given the paucity of safety data highlighted by York. Dental fluorosis is “primarily a cosmetic issue” (p. 23, col. 2): yet the Government replied to a Written Parliamentary Question on 20th April 1999 that it “is a manifestation of systemic toxicity” (Hansard, Lords, WA158). “Analyses . . have not shown any differences in total cancer rates . .”: Yiamouyiannis did so, in a better study (4.1) than Hoover’s.
Among the most serious is the treatment of the recent Newcastle study into bioavailability, which is cited in several places (e.g. pp. 28 & 29 col. 1; p.32 col. 1) as evidence that there is “no [significant] difference” in the absorption of natural and artificial fluoride in water, providing “further reassurance” on overall safety. Professors Trevor Sheldon of York and Stephen Holgate of Southampton are not alone in having pointed out that this grossly underpowered (n = 20) study did suggest a huge difference (over 30%), whose statistical significance, but not the strong trend, was removed by the authors illegitimately discarding an inconvenient outlier, thus reducing participants to 19.
There is more in terms of errors or distortions than can be listed here.
- Future research is largely passed over (there is no Index heading for this). “York identified the need for more good quality research” (p. 28 col. 1) comes as a surprise after what has been said or not said so far. The focus then shifts to the safer ground of the MRC (which was not a systematic review), and the lines of enquiry that it found “not of high priority”, while quoting extensively the purported bioavailability finding, and briefly citing the MRC’s two areas of weak interest in cancer (pp. 29, 31 col. 2). [Note: citation of two post-York studies into congenital abnormalities (p. 32, col. 2) highlights the Government’s failure to fund Cochrane-standard updating of the York review. Congenital abnormalities were an area of concern which York, but not MRC, pulled out. Since bias in reporting continues to abound on all sides, this is a serious matter, especially as the present document speaks of no “convincing” evidence of Down’s Syndrome in 2002, itself an unconvincing use or words.]
This document concludes: “it seems to us inconceivable that any adverse health effects would not by now have been uncovered”. This is in direct contradiction to York 12.4, and pp. xiv and 2, and to York’s verdict on the weakness of the existing safety studies; and it denies the experience of, for example, the careful work needed to link smoking and lung cancer. Three years later 3 distinguished writers in the British Medical Journal demonstrated how a “modest association between fluoridation and bladder cancer would be difficult to detect” with tools at the disposal of medical science (Cheng KK, Chalmers I, Sheldon TA. Adding fluoride to water supplies. BMJ 2007;335:699-702). There is no mention of the page of MRC research recommendations (6.2) which include the need to know “the effects of water fluoridation on children . .”
- Moving from the ‘science’, the document dismisses referendums and ballots without good argument (p. 39). They are a separate issue (the decision process) from the prior consultation process. In view of the 1990 advice of a U.S. fluoridation co-ordinator to “Avoid a referendum. The statistics are that 3 out of 4 fluoridation referenda fail”, BFS dislike of this method is understandable.
- “Clearly, fluoridation . . is not as extensive in Europe as it is in the US and elsewhere” (p. 72, col. 2) is an interesting way of recording that it is practically unknown on the continent of Europe. Biased selection applies in the description of the worldwide picture, and of US trends of acceptance which in fact go both ways. There is a rundown of all the countries that fluoridate (pp. 75-6), which is useful if it is accurate (no dates are given in a situation which often changes); there appears to be no key to references a – e.
- The environmental section makes no mention of the EU Dangerous Substances Directive 1976 which classifies a number of forms of fluoride as a danger to the aquatic environment. It concludes instead that fluoridation “could . . be described as environmentally friendly”.
- Evidence for public support relies exclusively on polls commissioned by supporters (Health Authorities, BFS, p. 86) with their preferred wording of questions. For obvious reasons these cannot be relied on. The “at least two thirds” public support they produced would in any case need to be shaded downwards by the recent figures from the London Assembly (38% in favour) and Scottish Executive (3% of individual non-dentist public + 25% of non-health-service organisations in favour), which showed less than full enthusiasm.
- The section on ethics relies on the views of selected supporters only. It conflates ethics with the safety question, which is a separate issue, and cites those courts which have upheld the right to fluoridate but not those that have judged it to be unjustified medication. It includes the statement that fluoridation evens out dental health inequalities, on evidence which independent York review scientists described as “weak, contradictory and unreliable”.
- Cost-effectiveness is taken as proved, without reference to York which found the evidence inadequate for any conclusions.
- Websites under ‘Help and Resources’ do not include the National Pure Water Association’s or any source unfavourable to fluoride, nor the York NHS CRD website www.york.ac.uk/inst.crd/fluoridnew which corrects the record about what the review “really found”. In short, One in a Million was written in order to make a case.