The long-standing debate about whether to fluoridate our drinking water continues.
Fluoridation is the addition of fluoride to public water supplies with the aim of reducing tooth decay. The fluorine, when mixed with water, becomes fluoride and the desired concentration of fluoride in the water is approximately one part per million, depending on the regional temperature and hence the amount of water children are likely to drink. Many studies, such as those by McClure in 1970 through to Burt in 1983, have shown that when children drink fluoridated water, their average rate of tooth decay seems greatly reduced. This apparently enormous benefit for children's teeth is the major argument in favour of fluoridation.
Three main grounds for opposition to fluoridation have been expressed. First, opponents claim the benefits are exaggerated or not established. Second, there are claims of health risks to parts of the population, for example, allergic reactions. It is also accepted that high levels of fluoride can cause discolouration of otherwise healthy teeth. Proponents do not consider this to be a problem in such small concentrations, whereas opponents disagree - especially because some people drink more water and could thus consume more than the standard 1 milligram of fluoride per day. Third, fluoridation is thought to be an infringement on individual rights because it is a compulsory medication of all members of a community.
An understanding of the fluoridation issue has important implications. If fluoridation is a beneficial and non-hazardous measure, then authorities may be justified in trying to educate the public to vote on, and not reject it on moral grounds.
Almost all studies that have been done have assumed that the scientific issues about fluoridation are unproblematic, and they have addressed the issue from sociological examination. The traditional view is that science is a special kind of knowledge, which is established by the scientific method and is objectively applied by members of a scientific community. However, in recent years there has been a major challenge to this picture by a sociology of science that shows how scientific knowledge is socially negotiated and variable, depending on the views of the relevant parties, both scientists and nonscientists. These challenges do not see science as objective, but rather as a form of social inquiry.
Kuhn (1970) argued that scientific knowledge does not always develop as an orderly process, but is characterized by periodic revolutions, in which the nature of scientific knowledge and the assessment criteria change in a fragmented way. According to Kuhn, the shift to the new scientific way of thinking is not necessarily based solely on the basis of clear rules of formal scientific practice, but can include social factors, though Kuhn has never developed a full analysis of what these might be. Collins (1975) took this concept further when he asserted that the outcome of experiments was not something whose meaning could be immediately comprehended, but rather something for interpretation, discussion between scientists, and reinterpretation in the light of other experiments.
One interpretation of this analysis of science is that traditional distinctions between facts and theories, and between scientific knowledge and values, can no longer be justified. Because social processes are involved at all stages of the creation, evaluation, and establishing of scientific knowledge, social values may also be involved.
In the same way as many scientists who study fluoridation have overlooked social values, sociologists have also downplayed an important part of the debate by ignoring the number of eminent scientists who have questioned aspects of fluoridation. An example is the study by Sutton in 1960, which analyzed the classic North American studies of the effect of fluoridation on tooth decay, and found that each showed significant methodological shortcomings. Sutton's detailed study throws doubt as to the extent of reductions in tooth decay from fluoridation. Most studies do not take in a single analysis of the fluoridation issue by sociologists.
In a situation of scientific uncertainty, differences in values are highlighted. A supporter of fluoridation might argue, “The evidence for benefits of fluoridation is quite substantial, while the evidence for harm is limited and dubious. I think the likely benefits outweigh the possible risks. Therefore, I support fluoridation because it is the cheapest and easiest way to make sure most children get the benefits.” An opponent might argue, “Although the evidence for the benefits of fluoridation is impressive, we don’t know the full cost. Since fluoridation is being forced on us, then it should require strong evidence that it does not pose a slight chance of harm. Some scientists claim that a small segment of the population may be harmed by fluoride. Therefore, I oppose fluoridation of water supplies and favour the voluntary use of fluoride tablets by those who want to take them.”
Both arguments consider the scientific evidence concerning fluoridation, but differ in their assessments of the social benefits and costs. This difference is not between rationality and irrationality but is a legitimate difference of values, for example, the positive value placed on good teeth, the negative value placed on possible health risks, and the social benefits or costs of compulsory or voluntary intake of fluorides.
From the sociological point of view, opposition to fluoridation is not necessarily irrational. Rather, claims to rationality and to scientific authority are best seen as part of a strategy to promote fluoridation than as incontrovertible statements of fact. Second, social values are likely to be bound up in any decision about fluoridation, so this is not an issue on which declarations by scientific experts ought to be considered the final word.