June 2009 - Hot Topic

Objections to Water Fluoridation: Is there something in it?

by Angus Dawson, PhD, Senior Research Fellow, Joint Centre for Bioethics, University of Toronto
Picture of Dr. Angus Dawson.

An increasing number of municipalities in Ontario have voted to end the fluoridation of their water supply. Those that object to water fluoridation tend to offer two ethical arguments about why it is wrong. First, they offer a ‘consent argument’: it is wrong to impose something without the agreement of the relevant parties. Second they offer a ‘harm argument’: fluoride is unnecessary and harmful. I suggest here that the ‘consent argument’ is not decisive and the ‘harm argument’ is usually based (at best) on selective reporting of relevant data and tends to ignore potentially important community benefits.

The objector’s message is a powerful one in today’s society with its commitment to individual choice and suspicion of government interference in people’s lives. However, focusing on individual consent in such cases makes no sense. I suggest we can set the ‘consent argument’ to one side because it works (or does not) equally in favour of or against fluoridation. The standard consent argument tends to be made by the objectors to fluoridation on the basis that fluoride is added to the water supply at a point where no one can opt out (except by buying their own drinking water). The individual has no choice and may not have consented. However, given the fact that well-organised groups of objectors have sought election with the aim of ending fluoridation of water, exactly the same argument can be used against them. If I live in a community that has no fluoridation, but I want my water to be fluoridated, I cannot attain my wish.

My point here is that this is essentially one of the paradoxes of this particular type of intervention: everyone is left with the same result, as long as the relevant majority are in favour of it. In such cases the ‘result’ may be fluoridation or not, and the ‘relevant majority’ may not be a true majority view in the relevant group. So the consent argument can be turned around and used to argue that objectors have imposed their view about what is best upon others without their consent. So, the focus should really be on general arguments about what gives legitimacy to choices about such policies, and how choices are to be made where a minority feel strongly about the impact of a decision that they cannot (easily) avoid.

It might be argued by the objectors that it is relevant that fluoridation is about adding something to the water but this is strictly irrelevant to any discussion of consent. The giving of consent is the act of giving permission for what follows, and there is no reason to see it as relating only to positive (adding) or negative (ending) acts. Whilst democratic structures may be the best we have, they are no guarantee of representative (or even sensible) decisions. Certainly there is little evidence that ending water fluoridation is the informed choice of the majority of voters. There is a practical lesson here for everyone that cares about public health: engagement with local political issues is essential.

So much for consent, what about the ‘harm argument’? The problem here is that the objectors to fluoridation tend to be (at best) highly selective about the scientific literature they cite and often just allege or insinuate potential harm from fluoridation. For example, one prominent anti-fluoridation website provides a long list of ‘risks’ as though they were equally well established, including dental fluorosis (for which there is evidence), but also increased risks of bone fractures (some dubious evidence) and cancers (no good evidence) [1]. The website is full of strong rhetorical claims such as: ‘the main fluoride chemical added to water (hydrofluorosilicic acid) is an industrial by-product from the phosphate fertilizer industry … It is an unpurified, industrial-grade, corrosive acid…’ [1]. This all paints a picture of unnatural and dangerous products dumped in our water through a conspiracy between government and the chemical industry. As with debates about raw milk and vaccinations there is a whole world-view here that unfortunately cannot be tackled through rational discussion about the evidence.

More importantly, there is a general problem with the way that objectors focus on harm. Arguably, everything, including doing nothing, involves some risk of harm. Therefore, it makes no sense to focus merely on harms: any evidence of harm must be weighed against potential benefits carefully. Objectors tend not to acknowledge the evidence in favour of fluoridation as a preventive dental health measure or as a contribution to tackling health inequalities in relation to dental caries [2]. We are owed an explanation as to why such issues don’t count as relevant considerations and why the promotion of greater social justice is not even on the table.

A good case can be made for continuing water fluoridation, but I think it is only fair to add that new research is needed to confirm its relevance in preventive dental care [2, 3]. The world has changed since many of the original fluoridation studies were performed and far more people have access to other sources of fluoride (such as toothpastes) [3]. But, of course, some do not. The potential impact (in terms of harms and benefits) needs to be considered carefully. Increasing fluorosis is likely to result in growing calls for the end of fluoridation, and supporters of fluoridation need not see the recent call for a reduction in the amount of fluoride in the water in Canada as a retrograde step [4]. If the benefits of water fluoridation are significant enough to really benefit the intended targets, such as those without other or inadequate means of preventive dental interventions, then it is time for public health to fight back. However, to do so, we need good quality relevant evidence [3].

References

[1] Fluoride Action Network. (no date). Frequently Asked Questions. (accessed: 7/6/09)

[2] Medical Research Council. (2002). Water Fluoridation and Health. London: MRC.

[3] Cheng, KK, Chalmers, I, and Sheldon, TA. (2007). Adding fluoride to water supplies. BMJ, 335: 669-702.

[4] Health Canada. (2008). Findings and Recommendations of the Fluoride Expert Panel [PDF] (January 2007). (accessed: 7/6/09).