• Howard Cohen, BA, MA, PhD • © J Can Dent Assoc 2001; 67(10):578-80
• David Locker, BDS, PhD •
© J Can Dent Assoc 2001; 67(10):578-80
A statement concerning the ethics of water fluoridation was published in a recent issue of the Journal of the Canadian Dental Association.1 The arguments presented in that paper did not constitute what we would consider a complete and systematic account of the scientific and moral issues involved. It is our contention that water fluoridation, by the very nature of the way it is administered, engenders a number of moral dilemmas that do not admit to any easy solution. In this paper, we attempt to elucidate the particular problems posed by this public health initiative, according to the principles of bioethics.
The Role of Bioethics
Beneficence and Autonomy
Advocates of water fluoridation argue that the benefits accruing to society through reductions in dental caries outweigh any harm to individual autonomy. Defenders of autonomy argue that fluoride is available from many sources, and so its benefits can be realized without violating the principle of autonomy. However, this presumes that everyone in society can access these alternative sources. The most vulnerable in society, it is countered, would surely miss out on the benefits of fluoride.1
Therefore, considering the benefit that accrues to disadvantaged groups in society, advocates of fluoridation contend that water supplies should be fluoridated on the grounds that everyone, regardless of socioeconomic status, can benefit. The claim here is that water fluoridation promotes social equity. This solution still leaves the conflict of beneficence and autonomy unresolved. In fact, there appears to be no escape from this conflict of values, which would exist even if water fluoridation involved benefits and no risks. However, water fluoridation does involve risks, in the form of increases in the prevalence and severity of dental fluorosis. Moreover, as Coggon and Cooper5 indicate, those most likely to benefit from water fluoridation are not necessarily those placed at most risk. This complicates considerably any attempt to balance beneficence and autonomy.
Advocates of water fluoridation, in seeking to strike a balance between competing values, are attempting to reconcile irreconcilables: the demands of moral autonomy cannot be made compatible with what could be regarded as the involuntary medication of populations. This situation gives rise to the question of which values concerning the conflict between beneficence and autonomy should inform decision making with respect to water fluoridation: those of health professionals or those of the community?
The conventional view is that policy-makers are presented with a clear moral choice when weighing the benefits and harms associated with water fluoridation. Historically this may have been the case. The original community trials of water fluoridation indicated a substantial effect.7,8 However, over the past 25 years there has been a marked reduction in rates of dental caries among children, such that the benefits of water fluoridation are no longer so clear. Although current studies indicate that water fluoridation continues to be beneficial, recent reviews have shown that the quality of the evidence provided by these studies is poor.9-11 In addition, studies that are more methodologically sound indicate that differences in rates of dental decay between optimally fluoridated and nonfluoridated child populations are small in absolute terms.12,13 Canadian studies of fluoridated and nonfluoridated communities provide little systematic evidence regarding the benefits to children of water fluoridation.14-17 Moreover, studies of the benefits to adults are largely absent,9 and there is little evidence that water fluoridation has reduced social inequalities in dental health.10
Truthfulness entails a proper appraisal of the benefits and risks. Currently, the benefits of water fluoridation are exaggerated by the use of misleading measures of effect such as percent reductions. The risks are minimized by the characterization of dental fluorosis as a “cosmetic” problem. Yet a study of the psychosocial impact of fluorosis found that “10 to 17 year olds were able to recognize very mild and mild fluorosis and register changes in satisfaction with the colour and appearance of the teeth.”18 The investigators also stated, “The most dramatic finding was that the strength of association of [fluorosis] score with psycho-behavioural impact was similar to that of overcrowding and overbite, both considered key occlusal traits driving the demand for orthodontic care.” In the absence of a full account of benefits and risks, communities cannot make a properly informed decision whether or not to fluoridate, and if so at what level, on the basis of their own values regarding the balance of benefits and risks.
In the absence of comprehensive, high-quality evidence with respect to the benefits and risks of water fluoridation, the moral status of advocacy for this practice is, at best, indeterminate, and could perhaps be considered immoral.
Ethically, it cannot be argued that past benefits, by themselves, justify continuing the practice of fluoridation. This position presumes the constancy of the environment in which policy decisions are made. Questions of public health policy are relative, not absolute, and different stages of human progress not only will have, but ought to have, different needs and different means of meeting those needs. Standards regarding the optimal level of fluoride in the water supply were developed on the basis of epidemiological data collected more than 50 years ago. There is a need for new guidelines for water fluoridation that are based on sound, up-to-date science and sound ethics. In this context, we would argue that sound ethics presupposes sound science.
Dr. Cohen has a PhD in political and moral philosophy from the University of Toronto. He is currently enrolled in the dental undergraduate program at the University of Toronto.
Dr. Locker is professor and director of the Community Dental Health Services Research Unit, Faculty of Dentistry, University of Toronto.
The views expressed are those of the authors and do not necessarily reflect the opinions or official policies of the Canadian Dental Association.
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