On Wednesday evening, nearly 400 Londoners squeezed into the Wolf Performance Hall in order to hear Dr Paul Connett warn his audience about the dangers of fluoridation. It was an impressive turnout for the head of the Fluoride Action Network who pronounced it the largest crowd he had spoken to anywhere. From the questions that followed the presentation, it was clear that most of those in attendance shared the concerns that he identified about the safety of adding fluoride to our water supply.
Similar concerns were raised with me and other councillors by Chris Gupta, a local activist who works with the citizens group, Waterloo Watch. The presentation that they provided for a few of us at city hall in 2008 was enough to prompt me to sit down with the head of our water department to discuss our practices at the city. I learned that, because of the issues raised by the National Research Council in 2006 pertaining to the link between fluoride and thyroid functioning, cancer and dental fluorosis, Health Canada was undertaking a full review of the matter.
That review was supposed to be completed in the spring of 2009. Although the research has been concluded and opportunities for public comment on the preliminary document ended in November 2009, the final report and recommendations have yet to be released.
Nonetheless, the conclusions are not expected to provide the impetus for much change in public policy. According to the London Middlesex Public Health Unit, in its review of the report, the available research does not support a link between exposure to fluoride in the drinking water at 1.5mg/L and adverse health effects with respect to cancer, reproduction, and a whole host of other concerns including lowered IQ.
Accordingly, Dr. Graham Pollett, London’s Medical Officer of Health, recommended that "the Board of Health support the ongoing fluoridation of the City of London’s drinking water supply as a measure to achieve optimal dental/oral health for all residents, which is an important component of total health." It did so unanimously. City council representative Denise Brown was absent.
London has been putting fluoride in its drinking water since 1967, following a plebiscite on the issue. At the time it was very controversial since for many it meant that we would be putting “rat poison” into the water, and because it, unlike additives in foods, it is very hard to avoid. Nonetheless, the thinking of the day was that the public health benefits in the form of reduced cavities in teeth outweighed those concerns.
But that was before we put fluoride in toothpaste allowing for a topical application rather than ingestion. It was also before fluoride applications at the dentist’s office were available. And it was also before many workers had benefits than included dental care.
It was also a time when we had little evidence on the effects of long term use, especially on bones. There is some indication that prolonged exposure to higher levels of fluoride may make the bones more brittle resulting in increased propensity to breakage, especially in women. This too may become an important health concern for an aging population.
Much of the research has focused on significantly elevated levels of fluoride that occurs naturally in the environment including in groundwater. In London the level is maintained at .7mg/L, about half of what is considered “safe”. But, given that it is the water as well as in various foods, it is difficult to determine the actual level of exposure for each individual. Some people drink a lot of water, some less.
Additionally, there are concerns about exposure by infants and young children who are most sensitive and for whom exposure is not recommended. How are they to avoid such exposure when it is in the drinking water?
To date, established authorities such as Health Canada, the American and Canadian Dental Associations and various public health bodies have stood solidly behind the fluoridation of water. The United States Center for Disease Control and Prevention has called it one of the ten great public health achievements of the twentieth century. Calls for a review have generally been dismissed. Dr. Connett thinks that this is largely due to the fear of lost credibility. Have we been doing the wrong thing all these years? And if so, how can these public agencies be trusted?
But it has been nearly half a century since London began fluoridating its water. There has been much research since then, enough to suggest that we should have another look. We need to review all the evidence, continue to engage the public, and make a decision whether to continue or not.
The use of fluoride in the water is for disease prevention, not for water safety. That makes it a medication which residents can’t decline to use. That being the case, we need to apply the precautionary principle, that is, to establish the safety of the product before we use it. We argued for the precautionary principle when we worked to eliminate the use of pesticides. It applies here just as well.
Fluoridation is considered to be an inexpensive means of reducing cavities especially among economically disadvantaged groups; the resulting high incidence of dental fluorosis is not considered to be a serious issue. However, isn’t it possible to provide topical applications through a public health program in the schools? That, plus fluoride toothpastes should be able to provide good results without exposing everyone to a medicine they may not want or need and which may have negative consequences.
I am not a scientist. I cannot adequately critique the research that has been done to date. I rely on experts to do that.
But the experts themselves do not agree. It seems to me there is enough disagreement among the experts to warrant reconsideration.
The 1996 Update of the 1996 Federal-Provincial Report on the Benefits and Risks of Water Fluoridation prepared for the Ontario Ministry of Health summarized its review as follows:
The main limitations of current research on the effectiveness of water fluoridation are its exclusion of adults and elderly and failure to consider quality of life outcomes. Since water fluoridation is a total population strategy, its benefits to the population as a whole need to be documented. Those benefits should encompass reductions in disease and contributions to oral health-related quality of life.
Research also needs to be undertaken to determine when and what level of dental fluorosis has a negative effect on those with the condition and the trade-offs the lay population is willing to make with respect to reductions in dental decay and increases in dental fluorosis.
Those outcomes and trade-offs need to be examined carefully. But ultimately, this is a political decision. That’s why fluoridation is not mandated by our provincial or federal governments; it’s a municipal responsibility.
A number of municipal jurisdictions have decided to stop fluoridation. Should London follow suit?
That’s a political choice. But first we need the evidence and the debate.
You can access the Health Canada Report here.