Prime Minister’s science advisor awry
Robert Mann & Ross Forbes
We interpolate comments on the PM’s extremist advice.
What is in the water?
Office of the Prime Minister’s Science Advisory Committee
URL: Click Here
June 12, 2013
In recent weeks we have seen a revival of the water fluoridation “debate”. Perhaps the question we need to ask is “what is the debate really about?”
The science of fluoride in water is effectively settled. It has been one of the most thoroughly worked questions in public health science over some decades. There is a voluminous scientific and lay literature that needs to be considered.
Professor Sir Peter Gluckman, much of whose medical research has examined the factors during pregnancy that create a healthy start to life, in particular how a baby’s environment from conception to birth determines its childhood development and lifelong health, has evidently not considered the key writings on the bodily effects of fluoride. He should start with Prof. Paul Connett’s book ‘The Case Against Fluoride’.
There is no doubt that the presence of low amounts of fluoride in water (either naturally occurring or adjusted to between 0.7 and 1 mg/litre) reduces the incidence of dental caries
There is extreme doubt, among scientists familiar with the evidence. The benefit, if any, is at most tiny.
Actually, natural fluoride in NZ waters was known NOT to be correlated with tooth decay, from before fluoridation was invented: Hewat, R.E.T. NZ Dent. J. 45, 157-167 (1949); Hewat RET, Eastcott DF. Dental Caries in New Zealand. Christchurch: Medical Research Council of NZ,1954.
Fluoridation would not have been allowed if these facts had been properly understood.
and this is even in advanced economies where dental hygiene has been much improved and where fluoride toothpastes are available. In some countries, fluoride need not be added to the water supply because their geology naturally provides water with fluoride in at least these concentrations.
Does Gluckman really believe that fluoride in natural waters varies according to national boundaries?
The landmark review was Diesendorf’s 1986 Nature paper ‘The Mystery of Declining Tooth Decay’, showing that the decline (approx. 3-fold) in decay rates over several decades was a set of parallel graphs for fluoridated and non-fluoridated states.
But for some decades, in countries such as New Zealand, where fluoride levels are very low in natural water, fluoride has been added to the water supply.
Notably, both the very young and the old benefit from fluoride in the water supply.
This claim of benefit for the old is not so usual as the standard mantra ‘we are helping the kiddies’. Fluoride does tend to make elderly bones more brittle, which is damage rather than benefit.
They develop fewer dental caries and thus have a significant reduction in the downstream effects such as the need for invasive dental surgery associated with problematic dental status. As in all populations the burden of poor dental health is considerably greater for those in less advantaged socioeconomic conditions and it is this population that benefits most from water fluoridation.
Nice PC line but not borne out by fact, e.g. Onehunga has natural low-fluoride water (from its own wells on the low slopes of One Tree Hill) and has far less dental fluorosis than in surrounding ARC fluoridated districts. Does it suffer the higher decay alleged by Gluckman? Facts are needed!
In other areas of the world, natural levels of fluoride in water can reach well above 4 mg/litre – this level is considered by authorities to be the level at which water is still determined to be perfectly safe for human consumption.
Wildly wrong! 4 ppm is known to cause significant skeletal fluorosis (harm to long bones), as well as frequent dental fluorosis.
It is absolutely clear that at doses used in New Zealand to adjust the natural level to a level consistent with beneficial health effects (0.7-1.0mg/litre), there is no health risk from fluoride in the water.
1. What Gluckman calls a ‘dose’ is notoriously not. The figures he quotes are for concentration (‘level’); the doses i.e mg of fluoride which people ingest are uncontrolled.
2. Several types of harm are suspected from 1 ppm fluoride including cancer, brittle bones, and mental handicaps.
Like any agent, including salt, sugar and water itself, if you eat or drink enough it can become toxic. At the doses used in New Zealand water, however, one would in all likelihood become very ill or succumb to water intoxication before any toxic effect of fluoride was discernable.
However there is one side effect of fluoride that is found even at this low level of fluoride in the water supply; in a portion of the population, it causes minimal white mottling of the enamel of the permanent teeth. This is very rarely discernible
Rubbish! Fluorosis is noticeable in an obvious minority.
and is definitely not the severe fluorosis that is so often pictured on websites of those opposed to fluoridation of the public water supply. The latter is associated with drinking water with very high naturally occurring levels of fluoride (more than ten times levels in New Zealand water after fluoridation) or from other sources of high fluoride – for example that found in some forms of black tea, generally in parts of Asia. The exposures needed are chronic exposures at levels many times that in our water supply.
So why is there any issue at all? There are at least two primary questions on which public debate seems to be hinged.
The first issue is an inherent challenge for any public health intervention: How to balance the common good of a population-based intervention with individual rights? This is primarily a question of societal values not science. Indeed, the balance between doing good (reducing caries) and not doing significant harm (minimal dental mottling) is scientifically clear.
When the reduction in caries is very slight if any, and the dental fluorosis matters more to some victims than Gluckman admits, this weighing is rather simple. It is not even necessary to weigh on the harm side the several suspected types of damage to health which, if proven, would tilt the balance further against fluoridation.
Thus in some ways any remaining debate has analogies to the immunization situation and to the imposition of regulations such as those requiring the wearing of seat belts. However whether to apply the science-based knowledge in this equation is a question of public health ethics and societal values.
The second issue is yet another values debate: Can food be used as a medium for delivering a public heath intervention? Is it OK for public water to be manipulated for an additional health benefit or for a potentially medicinal purpose? As it happens we already do so with iodine – our salt is iodised to prevent the developmental delay (cretinism) and goiters (big thyroid glands) associated with iodine deficiency and which was so common in New Zealand 100 years ago. There is no scientific issue here – it is purely an issue of values.
Correct. And no dispute is heard about adding iodine to salt. This is because there is no suggested harm, and the benefit is proven by long experience – an exceedingly different situation from fluoridation.
But because both such questions are values-based, for many people they are difficult to discuss. As with other issues where science and values are seen to converge – such as climate change – it is often easier for those seeking to advance values-based concerns to make the science sound scary or more uncertain than it really is. Indeed, it becomes a tactic amongst those who become passionate about their cause. Because biology and medicine are complex, studies can be difficult to put in perspective and odd results can be given undue weight. I have discussed this problem extensively elsewhere (Click Here).
The fluoride debate is based in no small part on numerous examples of inappropriate extrapolation from what happens at hugely higher doses of fluoridation, combined with what is frankly scaremongering. Further, because the way one looks for side effects following population interventions requires particular epidemiological approaches, the language of evidence-based medicine can be confusing to the non-expert and easily exploited.
With regard to fluoride, there have been genuine concerns raised regarding risks of bone disease, thyroid disease, brain disease and cancer. While these issues have been settled, they continue to be emphasized by those who oppose fluoride. Some of this continued emphasis is based on inappropriate interpretations of studies in rats or from humans who have fluoride poisoning or live in areas where there are extremely high concentrations of fluoride naturally occurring in the water or diet. Obviously the medical and public health science community has put a lot of effort into being sure that this is not the case at the doses being used to adjust natural levels in water.
‘Obviously’, huh? The fluoridation enthusiasts in the NZ Govt know the Hastings experiment was rigged and did not demonstrate inhibition of caries; and they have never spoken seriously of the several types of reasonably suspected harm.
Safety has been the subject of major assessments by many health authorities in Western countries. It is clear that there is no risk of such disorders at the doses of fluoride being used and extensive epidemiological surveys have repeatedly confirmed this to be the case.
So why does this concern continue? The misuse or inappropriate and alarmist use of science is a classic example of science being a proxy for values debates. Others, who have a more skeptical view of the medical-scientific sector, have seen this as some bizarre form of conspiracy.
Why so vague? Collusion to convert concentrated toxic industrial wastes into dispersed public “assets” is the logistical source of fluoridation (toxic wastes from aluminium smelters and superphosphate factories). If Gluckman deems those arrangements ‘bizarre’, so be it – but they are no less real therefore and he again confuses concentration with dose.
Regarding epidemiological surveys, the 1986 US National Institute of Dental Research survey of tooth decay of nearly 40,000 children in 84 US communities found, when raw survey data was released for independent analysis, that there was no statistical dental health difference between children who lived their whole lives in a fluoridated community, a non-fluoridated community or part of the time under each regime. Ironically, the lowest tooth decay rate reported in the survey occurred in a non-fluoridated area. Later analysis of the NIDR data came to a similar conclusion so why expose New Zealand communities to potential health risks with fluoride dispensed by way of their water supplies?
The NIDR survey was brought to Gluckman’s notice, among other fluoride related matters, in September last year.
Alternatively, it could be that it simply provides a platform for people looking for a cause to fight because of their personal ideology.
True, some activists have used the fluoridation issue as an arena in which they deem it ‘OK’ to behave abusively or crazily. In our experience, nearly all the bad behaviour has been by pro-fluoridation activists.
The scientific basis for stating that fluoride in water (at the concentrations recommended) is a safe and very effective approach to improving dental health is clear.
Rubbish. The ‘York’ review over a decade ago showed no such clear picture.
Where there is debate, it is with the values-based issues, even though these can be overstated. Sadly, rather than having dialogue on such values issues which is a proper discourse for society, the debate has been hijacked by a misinterpretation of science. Such values debates are critical for a healthy democracy, but they cannot proceed usefully if the debate is shifted inappropriately to another domain.
The Ministry of Health and its expert dental, public health and scientific advisors have been well positioned to opine on the science. Indeed their conclusions are in accord with other major scientific and public health authorities that have looked at the question repeatedly. But irrespective of the conclusions that the scientific community has reached, scientists do not have a privileged position within a values debate beyond clarifying when science is being misused. Such values based debates should focus on any real issues of contention and be resolved through the political process – whether local or nationally.
What Gluckman fails to recognise is that MoH and its various advisors are not well positioned to opine on fluoridation science. For example, the National Fluoridation Information Service was established under contract between the Ministry of Health and the Hutt Valley District Health Board to the tune of around $1.25 million. The contract has a laudable aim of maintaining an objective and credible viewpoint when reviewing literature and framing communications on water fluoridation (Service Specification, clause 2.3) yet in that same clause there is a requirement that the contractor will “not act in any way that may contradict or be inconsistent with Ministry policy on water fluoridation or with the MoH publication ‘Good Oral Health for All, For Life’,” both of which unequivocally advocate fluoridation.
This same Gluckman is an extremely enthusiastic proponent of gene-tampering experiments, attacking scientists who express misgivings.
He is a constitutive bully. While Dean of the Auckland medical school he issued a ‘gagging order’ to Professor Elliott (which was of course disregarded).
Gluckman tries to make out that the science regarding benefit and harm from fluoridation is settled. This is far from true.
Better studies would be interesting on most of the sub-topics mentioned, but meanwhile, the science now known is summarised: tiny or nil benefit and worrying evidence (not proof) of harm. That is no basis for Gluckman to bully the concerned public into silence on this issue.
Robert Mann, retired senior lecturer in biochemistry & in environmental studies, advised successive Ministers of Health about poisons on the Toxic Substances Board. Ross Forbes is a retired teacher & adminstrator with a long-standing involvement in conservation science.
ENDS