Socio-economic differences in public opinion regarding water fluoridation in Queensland

Objective: To describe public opinion relating to the fluoridation of drinking water in a sample of the Queensland population. Method: Data were collected by means of a computer-assisted telephone interview survey from a sample of the Queensland population. Descriptive statistics and logistical regression were used to examine associations between variables. Results: Seventy per cent of the total sample supported water fluoridation of their local supply. More than 71% of the total sample agreed that water fluoridation was safe. People living in areas of higher socio-economic/relative socio-economic advantage were more likely to support the addition of fluoride to local drinking water and agree that it was safe. Opinions about fluoridation varied by respondent age and gender. Conclusions: General support was found in this sample of the Queensland population for fluoridation of drinking water. Implications: In Queensland, fluoridation of the water supply is now a political decision. Information about public opinion on fluoridation may assist decision makers in the final determination. The safety and efficacy of fluoridation of drinking water has been the subject of much popular debate. In terms of efficacy, the scientific literature demonstrates that fluoride is effective in the prevention and reversal of dental caries1–6 and that the addition of low levels of fluoride to drinking water is a cost-effective public health intervention.7,8 Numerous studies have examined the safety of fluoridation. Although concerns about dental fluorosis, bone fracture and development, associations between water fluoridation and cancer, and the relationship between water fluoridation and congenital abnormalities exist, there is no clear evidence of negative health effects of water fluoridation aside from concerns relating to dental fluorosis.6,9,10 Despite being acknowledged as one of the 10 greatest public health achievements of the 20th century,11 the issue of fluoridation of public drinking-water supplies is often an emotionally charged debate12 and one that has the potential to effect policy decisions at various levels of government. The debate is ongoing in Queensland. Although more than 70% of Australians have fluoridated drinking water, the proportion of the Queensland population with access is less than 5%.13 The power to make the decision to fluoridate local water supplies is held by local government associations (LGAs), making it a political issue at the level of local government. There is evidence that poor oral health is associated with relatively low socio-economic status (SES)14,15 and that evidence also supports the assertion that water fluoridation reduces the oral health disparities between SES groups.16,17 Since fluoridation in Queensland is now a regional issue, and regional differences may potentially be manifest in inequalities in health access and outcomes, the purpose of this study was to measure public opinion about fluoridation of the drinking-water supply and to examine associations between support for fluoridation and socio-economic status.