www.keithrankin.co.nz/kra01OnehungaFluoridation.html

14 Mar 2001
 

The decision is about to be made over Onehunga's water supply. To fluoridate or not to fluoridate; that is the question.

A referendum of sorts was held among Onehunga residents. In a turnout that was about as high as you can ever expect to get for this kind of exercise (about one-third of ballots were returned) there was a two-to-one rejection of the proposal to fluoridate Onehunga's spring water.

A majority of members of the Maungakiekie Community Board and various commentators (most specifically the NZ Herald's Brian Rudman) believe that the residents' poll should be overridden on the grounds that the scientific evidence in favour of fluoridation is irrefutable, and on the claim that there may have been many more fluoridation supporters than opponents who for one reason or another did not return their ballots.

As a political economist who is equally happy to drink fluoridated or unfluoridated water, these kinds of anti-democratic rationalisations worry me.

First, the poll non-response rate is most likely due to a combination of ignorance and indifference. By ignorance, I mean an unawareness of fluoride. Probably for a substantial minority of people, water is simply water, toothpaste is simple toothpaste, and fluoride is a meaningless word on the side of a toothpaste tube.

Of those Onehunga residents who do have an opinion, the weight of opinion is clearly and substantially against fluoridation. In this regard, the Onehunga poll is almost certainly more reliable than the referendums held with the general election in 1999. In those polls, many people who would not have chosen to participate felt obliged to fill in ballot papers that they were not expecting. Such voters responded to the leading questions asked of them in an entirely predictable manner.

Second, the "technocrat knows best" argument has failed us on a number of occasions in the past; eg Freudian psychology, DDT, thalidomide, mad cow disease and the wanton use of antibiotics are examples that spring to mind. The issue is not that there may be a conspiracy to dispose of waste fluoride by unloading it into our water. Rather it is the possibility of unintended harm occurring to at least some members of the public.

Third, the main beneficiaries of fluoridation are children. But we need to consider children of different ages. Few would doubt that 10-year old children who don't use fluoridated toothpaste are better off with fluoride in the water. But are the marginal benefits of water fluoridation to a 2-year old child who regularly swallows substantial amounts of fluoride toothpaste greater than the possible harm?

Fourth, what research has been done to contrast the dental health of Onehunga children with those of say Glen Innes or Mt Roskill? Fluoridation proponents assert that children in Onehunga have more tooth decay. No doubt they are right. But how much more decay? And is that statistic attributable to socio-economic status, to ethnicity, or to the absence of fluoride in the water? We recently heard about the severe dental problems of poor Maori children in Northland. Onehunga also has its share of poor children.

Herald readers would be well served by a clear unbiased presentation of the evidence of children's dental health in different parts of the cities of Auckland. Simple statistical techniques are available to compare data from suburbs with varying socio-economic characteristics. We can only feel confident about the value of fluoridation when the results of such straightforward research are presented to the public for comment and informed debate. The matter is of interest to all Aucklanders, not just the residents of Onehunga.

Fifth, to what extent are dental health problems caused by fluoride-induced complacency? I am reminded of a Herald correspondent last year who suggested that the road toll would come down if driver air bags in cars were replaced by spikes. Then people would drive more carefully, and fewer pedestrians and cyclists would be killed. It is my understanding that, worldwide, dental health problems have been worse in towns that have removed fluoride than they ever were before fluoride was first introduced.

All of Auckland benefits if one part of Auckland has unfluoridated water. Call it an ongoing experiment if you like. Keeping Onehunga unfluoridated means that researchers will be able to study the effects of fluoridated water over the long term. Onehunga serves as the control group.

Further, a continuance of the status quo will mean that both supporters and opponents of fluoridation can choose to reside in a place that suits them. As economists say, "the customer is always right". That maxim applies to public goods as well as to pizzas and meat pies.

According to one claim advanced in the "Catching the Knowledge Wave" project, the world's knowledge doubles every seven years. Who knows what this exponential growth of future knowledge will reveal about fluoride?

The more we know, the more we upwardly revise our estimates of what we don't know. A future 'knowledge society' will be more humble than our society of the 20th century was. Last century, too many of our decision-makers believed they knew everything that there was to know.

Fluoridation is a small matter that raises big questions.
 

Rankin File