In the U.S., water fluoridation has been a standard policy since the 1950s. As of 2012, 72% of the U.S. population receives water with added fluoride. Fluoride, in appropriate amounts, is known to reduce the likelihood of cavity formation. In Australia, water fluoridation is more controversial. And in Queensland, Australia, over 20 city councils have refused to add fluoride after being given the choice to add it in 2012.

Queensland chief dentist Dr. Brown says that the benefits of added fluoride are clear, and that local governments chose to resist reviewing evidence that suggested as much. The various government councils, though, have stood by their decisions, and continue to downplay the potentially negative impact it might be having on the teeth of local residents.

Some council people seemed to be afraid of the risks with over-fluoridation. “It might protect your teeth but if you get too much fluoride your bones go brittle, said Blackall-Tambo mayor Barry Muir. “You end up with a real lot of old people who might have good teeth but they can’t move anywhere because their bones are fractured.”

Fluoride does not cause any health issues, though, unless it is present in very high milligrams per liter — much higher than it would ever be found in drinking water. Even then, the most common side effect is dental fluorosis (teeth staining), not weak bones. Studies by various research bodies and health organizations, including the Harvard School of Public Health, and the U.S. Public Health Service, have found no links between fluoride and weak bones, or cancer.

Many of the local councils might be, ultimately, choosing not to fluoridate the water since the service costs cities several thousand dollars each year. Mayors like Rob Chandler, who represents Barcaldine, say that there is naturally occurring fluoride in their water, even though the fluoride levels are below what Queensland Health recommends.

For the towns that continue to support water fluoridation, the current state of their teeth is all they need to know. “I come from a city that’s had fluoride in the water for the better part of five decades and today it shows that those results work,” said the Mundingburra MP David Crisafulli, in an interview with the Courier Mail.