Aerial view of downtown Calgary, Alberta, September 2021. (AceYYC /CC BY-SA 4.0)
The City of Calgary is reintroducing fluoride back into its drinking water, saying it helps prevent tooth decay. The city had removed the mineral from its water system in 2011.
Effective June 30, fluoride levels will be maintained at “optimal” concentrations of 0.7 milligrams per litre, according to Health Canada’s guidelines, the city says on its website, noting that the mineral is “naturally found in water, air, soil and almost all foods” in lower levels.
In a city-wide plebiscite in the 2021 civic general election, 62 percent of Calgary residents voted in favour of fluoridation in the drinking water system. Four years later, the city is implementing the refluoridation, stating that it’s a “safe and effective public health measure to prevent dental cavities and improve oral health.”
In 2011, fluoride was removed from Calgary’s drinking water after Calgarians expressed that they wanted it gone, city councillor Gian-Carlo Carra said in a radio interview with NPR in December 2024. He said that, while managing its $4 billion annual budget, the city decided not to upgrade its worn-out fluoride injection system rather than invest in a $20 million upgrade and continue to incur about $1 million a year in operating costs.
Now, Calgary rejoins a host of Canadian cities that either fluoridate or have refluoridated their drinking water supply, including Edmonton, Winnipeg, Ottawa, and Toronto. A number of cities and provinces do not fluoridate or have defluoridated their drinking water, including Newfoundland and Labrador and various communities in British Columbia.
Both Health Canada and Alberta Health Services state that fluoride is beneficial in preventing tooth decay.
However, the use of the mineral has received more scrutiny in the United States.
A report by the U.S. National Toxicology Program notes that fluoride exposure is associated with lower IQ in children.
In 2024, U.S. District Court Judge Edward Chen in California ordered the Environmental Protection Agency to strengthen its regulations on drinking water. “The scientific literature in the record provides a high level of certainty that a hazard is present: fluoride is associated with reduced IQ,” Chen wrote in the ruling.
U.S. Health and Human Services Secretary Robert F. Kennedy Jr. on April 7 announced he would tell the Centers for Disease Control and Prevention to stop recommending fluoridation in municipal water nationwide, citing concerns about the impact on children’s IQ.
Michael Wing is a writer and editor based in Calgary, Canada, where he was born and educated in the arts. He writes mainly on culture, human interest, and trending news.