London’s medical officer of health has been called upon, again, to make a case for keeping fluoride in the city’s water supply.
Dr. Chris Mackie will be speaking at Tuesday afternoon’s civic works committee meeting about what public health agencies consider to be a “safe, beneficial, equitable, and cost-effective” measure to prevent tooth decay.
According to his report, he’ll recommend the city keeps practising water fluoridation at a level of 0.6-0.8 milligrams a litre.
Asked why the issue was coming before councillors, Mackie said a delegation of fluoride opponents came before the committee under the previous council, who deferred the matter to the new council.
Mackie said he saw the presentation as an opportunity to address and highlight the importance of dental health, and how many Ontarians don’t have access to dental insurance.
In its report, the health unit estimates if the city stopped putting fluoride in the water, kids would experience at least 40,000 more cavities over the next 10 years.
“If we lost water fluoridation, it would be a big problem, especially for the people who are most vulnerable,” he said. “It’s also an opportunity to talk about science. Do we want to have policy decisions based on an objective view of the science, or do we want to go with an advocacy position where people are picking and choosing the evidence they want us to look at.”
Opponents to fluoride argue not enough is known about what they say are possible health risks such as cancer, bone disease and fluorosis, in which too much fluoride causes teeth to discolour, and say adding fluoride violates people’s Charter rights by medicating without consent.
The health unit says there is no evidence to support a link between exposure to fluoride in drinking water at the levels used in London to adverse health effects, including any types of cancer, developmental defects, neurobehavioral effects, or genotoxicity.
While federal and provincial governments set guidelines for fluoridation, the decision is left up to municipalities.
“Are there questions, are there concerns? The health risks that get associated with fluoride are the sorts of things that happen at way higher doses,” Mackie said.
“If you have fluoride naturally occurring in your water that is at a way higher dose, which is fairly common… in other places of the world, you can’t have negative health impacts. It’s the same as anything. You take one Tylenol you can cure a headache. You take a whole bottle of Tylenol and you can wreck your liver.”
Several communities across Canada have chosen to remove fluoride from drinking water, with Calgary being the most notable example. The city discontinued the practice in 2011 and rejected setting up an expert panel to study the issue.
Since then, the city has seen a rise in tooth decay rates compared to Edmonton where water is still fluoridated. A University of Calgary study looking at Grade 2 students in both cities found the number of decayed tooth surfaces per child rose by 3.8 in Calgary and 2.1 in Edmonton.
A similar uptick in tooth decay rates in Windsor, Ont. prompted that city’s council to reverse its 2013 decision to end fluoridation late last year.
Despite what the lack of fluoride has done to the teeth of those city’s children, Mackie says the information gleaned from those real-world examples has added to the scientific literature.
“All we’ve had in the past is ‘when you have fluoride, how does it improve dental health’? And then people argued ‘well, there’s lots of toothbrushing now, we don’t need fluoride.’ Now we see, even though toothbrushing is well taken up as a health behaviour, you still see a massive impact when you take fluoride out of the water.”
With files from Matthew Trevithick and The Canadian Press