Robert F. Kennedy Jr. pledged that one of his first acts in the new Trump administration would be to “advise all U.S. water systems to remove fluoride from public water.”

However, water fluoridation is usually determined by local governments, and it’s uncertain whether Kennedy would have the authority to mandate municipalities to eliminate the cavity-fighting chemical.

Pennsylvania residents can check to see if their water is fluoridated by inputting their address on the PA Coalition for Oral Health website’s interactive map.

In Pennsylvania, every water system is able to decide and vote whether to pursue regulation of fluoride in water — which has left about half of the state with fluoridated water, said Helen Hawkey, executive director of the PA Coalition for Oral Health.

The Municipal Authority of Westmoreland County doesn’t fluoridate the water in its service area, but some of the water it sells to other water systems in Western Pennsylvania is fluoridated, said Matt Junker, spokesperson for MAWC.

For example, when Plum and Monroeville switched to using water from MAWC, the communities decided they wanted fluoride.

In 2003, Shaler commissioners voted to keep its water fluoride-free.

About 75% of Americans receive fluoride in their tap water, according to the Centers for Disease Control and Prevention.

A federal review by the National Toxicology Program at the National Institutes of Health published in August found an association between lower IQ in children and higher levels of fluoride. However, the findings were based on studies where fluoride levels were about twice the recommended limit for U.S. drinking water.

Fluoridated water is largely the same as regular water, just with one added step in the engineering process, Hawkey said.

Though it’s not typically added to bottled water, when fluoride is added, the U.S. Food and Drug Administration says the total amount of fluoride — added plus naturally occurring — cannot exceed the recommended amount of 0.7 milligrams per liter.

Brita filters aren’t designed to remove fluoride, according to the company website. And refrigerators’ water filters cannot completely filter fluoride either.

The American Dental Association on its website says water fluoridation can reduce dental decay by 25% in children and adults.

John Pawlowicz, president of the Dental Society of Western PA and retired dentist who owned a practice in Butler and Mars, said he believes fluoride isn’t that big of an issue.

He said the bigger concern should be on “chemicals more detrimental than fluoride” — potential forever chemicals in day-to-day household items like clothing, makeup, cooking utensils and carpeting.