Water fluoridation continues to be a contentious public health policy. Recent moves to introduce schemes in England raise important questions about the use of evidence in public policy. Of particular concern is how evidence is used for public health policy-making purposes. This article reviews some of the key debates about water fluoridation and examines the way evidence has been promoted and used. The background to water fluoridation is discussed and also key ideas about how evidence influences policy. While traditionally the problem of evidence is characterised as one where policy makers either accept or ignore evidence, a central concern of this article is where poor evidence is promoted by professionals and accepted by policy makers. The article then examines the evidence on the effects of water fluoridation. Drawing on the idea of the ‘Gold Effect’, the article shows how deeply held beliefs about public health actions shape not just policy but also the application of evidence itself by professionals and researchers.
1.There are current proposals to introduce water fluoridation in a number of areas in England including Southampton, Bristol, parts of Yorkshire and the North West. In Southampton, 72% of those consulted opposed the scheme but the SCSHA still voted to go ahead with the scheme on the basis that they felt health benefits outweighed all other considerations. Recent proposals by the new coalition government about substantial NHS reorganisation and the abolition of SHAs and local PCTs and far-reaching changes to the organisation and delivery of public health services in England mean that the current legislation will need to be changed (Secretary of State for Health 2010).
2. Proponents of water fluoridation refer to the ‘optimum dose’. However, technically this is not a dose as would normally be understood as a dose of medicine as it refers to levels of fluoride in water. Therefore in this paper it is referred to as the ‘opitmal concentration’.
3. There are a number of different measurement scales for assessing the degree of dental fluorosis. The first was developed by Dean which provides six levels – no fluorosis, questionable, very mild, mild, moderate and severe fluorosis and is based on assessment of the front two teeth. The Dean index is widely used and supported by WHO. In addition, there are other classification and description methods of assessment including the TF index based on histologically identified changes in enamel, the Tooth Surface Index of Fluorosis and Young’s description of location, colour and hypoplasia. See Browne et al. (2005 Browne, D, Whelton, H and O’Mullane, D. 2005. Fluoride metabolism and fluorosis. Journal of Dentistry, 33: 177–186. ) for a full discussion.
4. Guidance to the NHS by the Chief Dental Officer in 2008, statements by Ministers in Parliament and papers produced by SCSHA for the consultation consistently state that there is no evidence of harmful effects.