| Stuart Cooper is used to ridicule. Health experts have accused him of peddling conspiracy theories, wearing a “tin foil hat” and being part of the John Birch Society, a right-wing group that once claimed that fluoridation was part of a Communist mind-control plot. But lately, Cooper and others who oppose adding fluoride to drinking water have been riding high, thanks to a federal court decision and the stunning rise of Robert F. Kennedy Jr. In recent weeks, a handful of communities, from Winter Haven, Florida, to Thermopolis, Wyoming, have voted to ban fluoride in water. “If you look into it a small amount, particularly the infant exposure aspect, you realize that this is a flawed practice and it needs to end,” says Cooper, who is executive director of the Fluoride Action Network. The connection between fluoride and dental health was first made in the early 1900s, when a dental school graduate noticed that many people in a Colorado town had brown-stained teeth from drinking water with high levels of the naturally occurring mineral. Researchers later discovered that fluoride can help prevent cavities. So for the past 80 years, towns have added low levels of fluoride to their drinking water to prevent tooth decay. Today, 72% of Americans using community water systems drink fluoridated water, according to the Centers for Disease Control and Prevention, which named the practice one of 10 great public health interventions of the 20th century. But a few developments have knocked fluoride defenders on their heels. A first-of-its-kind study suggested that fluoride exposure during pregnancy could be linked to neurobehavioral issues in children. Health experts raise doubts about the recent research. Some suggest the number of women who participated in this study and the single urine sample collected was too small. The results could be influenced by other factors, says David Juurlink, a toxicologist, researcher and professor of medicine at the University of Toronto. Even the study’s authors say that there should be fluoride in drinking water. “I have yet to see a study of this issue that is not riddled with methodologic limitations,” Juurlink said in an email. In September, a federal court judge ordered the Environmental Protection Agency to tighten rules on fluoride in drinking water, saying it poses a potential risk to children’s developing brains. And in November, Kennedy tweeted that fluoride was an “industrial waste” with links to various health threats, and that President-elect Donald Trump plans to advise all water systems to remove it. A few weeks later, Trump nominated Kennedy to lead the Department of Health and Human Services, which would give him a top role in federal health policy. Professional health associations still support adding fluoride to tap water, with the American Dental Association calling it “the single most effective public health measure to prevent tooth decay.” “We’re science-based,” says anti-fluoride activist Cooper. “But when we bring this information to the public, immediately we hear the scientists’ ridicule.” Now, with Kennedy poised to have outsized influence over public health, Cooper has a powerful new ally. — Gerry Smith | 
