TORONTO – Putting fluoride in municipal drinking water may be more trouble than it is worth, according to a newly released government report.
The report, commissioned by the federal and Ontario governments, suggests that fluoridation has minimal benefits and even some risk.
The evidence suggests that tooth decay is less common in communities with fluoridated water, but the difference is so small it is often not statistically significant and “may not be of clinical significance,” said the report by Dr. David Locker, a University of Toronto dentistry professor.
Meanwhile, he found that fluoridation seems to increase the rate of fluorosis, a condition that can leave pits and white marks on teeth.
The report says the benefits of fluoride are particularly questionable in areas with low rates of tooth decay.
“In such communities, a careful assessment of the balance between reductions in dental decay and increases in dental fluorosis should be undertaken,” he urged.
The study also suggests more research is needed on the actual advantages to “quality of life” from fluoridation. The lack of such evidence “undermines the credibility of fluoridation as a public health initiative,” said the report.
An estimated 40% of Canadians use water that has been infused with trace amounts of fluoride, a substance proven to prevent cavities.
The country’s largest association of dentists said yesterday it still stands by the practice as a valuable way to stave off cavities.
“It’s the most cost-effective public health effort to reduce tooth decay,” said Dr. Burton Conrod of Sydney, N.S., the president of the Canadian Dental Association.
But Dr. Conrod acknowledged the dose of fluoride in drinking water has been reduced because the chemical is now available from such sources as toothpaste and packaged foods prepared with fluoridated water.
Debates over fluoridation have raged since cities began putting it in drinking water decades ago. In Kamloops, B.C., a city resident is suing three levels of government over health problems he blames on fluoridation.
Dr. Hardy Limeback, another University of Toronto dentistry professor, has said there is no need to put fluoride in water because it is present in various other sources. He says children are getting too much fluoride in communities where it is added to the water.
The Ontario-federal report reviewed numerous studies conducted around the world in the past five years on the risks and benefits of fluoridation.
Although completed about a year ago, the report has only just been released by the Ontario Health Ministry. A provincial government spokesman was not available for comment yesterday.
The study was also commissioned by the federal First Nations and Inuit Health Branch.
Dr. Locker noted that in a few studies that looked at cities that had discontinued it, the rate of tooth decay did not increase to any significant degree. He also found few studies look at the risks and benefits of fluoridation on adults.