Hamilton's board of health is pressing Health Canada for proof that having fluoride in our drinking water is safe.
Councillors voted this week to ask the federal agency for reassurance, and to ask the province for proof of toxicology studies on the fluoride used in Hamilton's water.
The unanimous vote was moved by Coun. Brian McHattie, who said he's asked for information on fluoride but hasn't gotten the answers he wanted.
While he's "not quite ready to make the decision" to remove fluoride from the water, McHattie said he's concerned.
"My worst fear is that seven years from now, there will be definitive science that says there are links to cancer and other diseases, and we've supported it for 60-plus years," he said. "That would be the worst case scenario."
The letter comes after two months of debate at board of health meetings. In April, eight people spoke on the issue, most of them against fluoridated water. This week, Cindy Mayor of Waterdown encouraged councillors to write the letter.
Fluoride an 'easy toxin' to reduce
Mayor has spent five years and about 30 hours per week researching the impact of fluoride in drinking water. She has spent hundreds of dollars on Freedom of Information Act requests to the city.
"If you look at the toxins we have in our lives today and the need to reduce them, [fluoride] is the simplest one we can get out of our lives," she said. "We already have fluoride from other sources that we didn't have back in the 1940s when they started to put this in the water. We're ingesting about five times as much as we did back then. That alone is quite a concern."
Fluoridated water has become an issue in some communities across Canada. Earlier this year, Halton heard 10 hours of presentations before it decided to keep fluoride.
Peel Region heard from 20 presentations before it voted to keep fluoridating. Other communities, such as Calgary, Amherstburg, Ont., and Moncton, N.B., have recently voted to remove fluoride.
The rate of fluoride in Hamilton's water is 0.6 parts per million (ppm). City water has been fluoridated since 1966, said Dr. Chris Mackie, the city's associate Medical Officer of Health.
City reviews latest research
The fluoride in Hamilton's water undergoes a number of safety checks, Mackie said. The manufacturer, Solvay Chemicals, provides a certificate of analysis. Then the National Sanitation Foundation (NSF) certifies the chemicals.
The city has also tested the fluoride and discovered it was as good or better than the certificate of analysis claimed, he said.
The issue was revisited in 2008 when the city upgraded its water treatment facilities. Since then, city staff annually reviews the latest fluoride research, Mackie said.
There is evidence against fluoridation, Mayor said. She points to research showing that fluoride of 1 ppm is linked to Alzheimer-like symptoms, and that formula-fed infants could be getting too much fluoride.
She's confident that as the board goes through the stages of investigating the issue itself, it will be alarmed.
"If they're really diligent in their letter writing to Health Canada and the Ministry of Environment, if they start seeing answers they get, they'll find out it could be very unsafe," she said.
Decay rates were 'staggering'
Stephen Birch, a McMaster University health economist, is a proponent of fluoride. He's given presentations to councillors in London and Halton about the dental benefits for residents with low incomes.
Water fluoridation is the only truly equitable health care policy in Canada, he said.
Canadians support equitable health care, he said, yet "removing fluoride from the water would be doing just the opposite," he said.
Dr. Larry Levin, longtime Hamilton dentist and past president of the Ontario Dental Association, said he has seen the positive impact fluoride has on young patients.
"The decay rates we used to see in children were staggering," he said. "Disadvantaged children were constantly repairing their teeth. Now that we have an alternative, why would we do anything different?"