Utah to Become First State to Ban Fluoride in Public Water

Utah Gov. Spencer Cox said he would sign a bill that bans the use of fluoride in public water systems, rejecting the practice that many public-health experts say is a crucial protector against tooth decay.

The Republican governor said half the state already doesn’t have fluoride added to the water and that dentists he had spoken to said there haven’t been dramatic differences between the different counties.

“It’s got to be a really high bar for me if we’re going to require people to be medicated by their government,” said Cox on ABC4 Utah.

“It’s not a bill I felt strongly about; it’s not a bill I care that much about, but it’s a bill I will sign,” he said.

The Utah law is set to take effect in early May. It will be the first state with such a ban.

Most public-health agencies and doctors say fluoride should be added to drinking water to prevent cavities and boost oral health. The Centers for Disease Control and Prevention, which has called fluoridation one of the 10 great public-health achievements of the 20th century, said it reduces tooth decay by about 25%.

Critics have said that high fluoride exposure is linked to neurodevelopmental problems—and that given its availability in toothpaste and other dental products, it isn’t necessary to require everyone to ingest it through the water supply.

Dr. Richard Valachovic, a professor at NYU’s college of dentistry, said there is no reason to be concerned about the small amount of fluoride added to water in the U.S. “Anything in excess can be damaging. You can drink too much water and have damage because of that,” said Valachovic.

“The issue is that the studies that have been done that relate to neurological damage are at much higher levels, much higher levels than what we’re talking about in community water fluoridation.”

Laura Briefer, the director of Salt Lake City’s Department of Public Utilities—which provides fluoridated water to more than 365,000 people—said defluoridating could be especially harmful to residents who don’t have easy access to healthcare and dental care.

“I just think that we could have addressed this in a more measured and prudent way, so that we don’t have unintended consequences to some of our most underresourced communities,” she said.

The American Dental Association urged Cox in a letter to veto Utah’s bill, warning it “proposes to take the unprecedented step of ending one of the most trusted and tested public health strategies in the arsenal of preventive medicine.”

Typically, local municipalities decide whether to add fluoride to their water, though some states require water systems of a certain size to fluoridate. Lawmakers in states including Kentucky and South Dakota have filed bills to challenge those mandates.

Lawmakers in states including North Dakota, Tennessee and Montana have also attempted to follow in Utah’s footsteps and pass bills banning the practice statewide.

As of 2022, about 72% of the U.S. population on community-water systems were receiving fluoridated water, according to CDC data. However, many European countries, such as France and Germany, don’t add fluoride to their water.

Some cities that chose to defluoridate later added fluoride back to the water supply. The Canadian cities of Calgary and Windsor both chose to refluoridate after studies found an uptick in tooth decay.

Critics of the practice notched a victory last year when a federal judge in California ruled that the CDC-recommended fluoride level—0.7 milligrams per liter—posed an unreasonable risk of harm. The judge said the fluoride level didn’t comply with federal standards requiring an exposure level below one-tenth of the level at which a substance is hazardous. He ordered the Environmental Protection Agency to take regulatory action in response, but didn’t specify what it should be.

The criticism of fluoride as an additive gained greater prominence with the ascendance of Health and Human Services Secretary Robert F. Kennedy Jr.

He called the mineral “an industrial waste” in a social-media post late last year.

“I was called a conspiracy theorist because I said fluoride lowered IQ,” Kennedy said at his confirmation hearing. “JAMA published a meta-review of 87 studies saying that there’s a direct inverse correlation between IQ loss.”

Kennedy appeared to be referring to a review published in the Journal of the American Medical Association Pediatrics. The review, which analyzed 74 studies, found that exposure to high levels of fluoride was associated with lower IQ scores in children. The levels studied, however, were more than twice as high as what is recommended by the CDC—and the authors noted that many of the studies had a high risk of bias.

Stuart Cooper, executive director for the Fluoride Action Network—which is opposed to fluoridation—said he doesn’t think adding fluoride is worth the risk.

“A cavity can easily be filled, but damage to the brain is permanent and has significant lifelong consequences,” he said.

Valachovic, the dentistry professor, disagreed. “Using this broad paintbrush approach, that any level of fluoride can cause neurotoxic effects, is just wrong,” he said.

Write to Victoria Albert at victoria.albert@wsj.com