Fluoride Frenzy
UIC professor and dental public health expert Dr. Scott Tomar lends perspective to media outlets and clinical dentists as fluoridated water generates swelling attention.
Intro
Fluoride is under fire. Again.
Last August, the National Toxicology Program (NTP), part of the Department of Health and Human Services (HHS), released a headline-grabbing report detailing an association between fluoride exposure and children’s neurodevelopment. The “Monograph on the State of Science Concerning Fluoride Exposure and Neurodevelopment and Cognition” linked fluoride in drinking water at more than twice the recommended limit to lower IQ in children.
Then, three months later, Robert F. Kennedy Jr., the nominee to head HHS, generated attention when he signaled ambitions to remove fluoride from public water.
Mainstream media outlets such as CNN, NPR and NBC News began re-examining fluoride’s presence in the nation’s drinking water and turned to expert voices like Dr. Scott Tomar for comment. Over recent months, Tomar, professor and associate dean for prevention and public sciences at the UIC College of Dentistry, has offered measured perspective to local media such as The Chicago Tribune and WGN Radio as well as national outlets like The New York Times.
Tomar, a member of the National Fluoridation Advisory Committee, the American Dental Association’s standing panel of experts providing advice about the safety and effectiveness of fluoride, discusses the latest charges against fluoridated drinking water as well as how practicing dentists might discuss the issue with concerned patients.
Can you provide a snapshot history of fluoride’s intentional addition to drinking water, including concerns about this practice?
There was a series of studies in the 1930s noticing an association between tooth decay and natural fluoride levels in drinking water. It led to a theory in the early 1940s that if we could adjust fluoride levels to an appropriate level in drinking water, we could reduce the prevalence of tooth decay to mimic the preventive effect of naturally occurring fluoride levels. This prompted four pioneering studies in the 1940s in which one city adjusted fluoride levels while another local city, as comparison, did not. Researchers found a sweet spot – about one part per million fluoride in the water – in which there were low levels of tooth decay and low levels of fluorosis, a discoloration of dental enamel that occurs when fluoride exposure is too high during tooth development.
Since communities across the country began actively incorporating fluoride into their drinking water, rates of dental decay in children and adults have fallen dramatically, which has been a positive for human health overall. At the same time, a small but vocal minority has tried to tie fluoride to a wide range of conditions, such as cancer, osteoporosis, thyroid disorders, immunosuppression and Down Syndrome. All of these claims have been soundly refuted by scientific literature. The attention to children’s IQ is the latest attempt to question the safety of community water fluoridation.
Is the concern about fluoride exposure and children’s IQ warranted?
Absolutely not. A lot of people have critiqued the NTP’s recent systematic review in which 55 of the 72 studies came from countries such as China, India and Iran, which have a range of other pollutants in their water systems. By and large, the studies are low quality and considered high risk for bias. The NTP found no association between IQ and the levels of fluoride used in community water fluoridation.
What’s being explored in this area now and where do you see this issue heading?
To be certain, if there are questions, then we should design thoughtful, detailed studies to test those questions.
There’s a just-published study out of the University of Queensland in Australia, where drinking water is pretty widely fluoridated – more so than the U.S., in fact – that followed a cohort of children for a decade. The study tracked their fluoride exposure and took in detailed information on where the children lived and other key factors like socioeconomic status. That study found zero relation between fluoride exposure and negative cognitive development.
How would you suggest practicing dentists talk about this issue to patients?
We should certainly respect patient concerns, but it’s important to point out that public health policy is based on the best available evidence. We have 80 years of credible evidence that fluoride in drinking water at low levels – 0.7 milligrams per liter, or the equivalent of three drops of fluoride in 55 gallons of water – helps prevent tooth decay and has no adverse health effects, including on children’s neurodevelopment. That is why community water fluoridation continues to be strongly supported by major health authorities, including the U.S. Centers for Disease Control and Prevention, the American Public Health Association, the World Health Organization and the American Academy of Pediatrics.
Now, the use of other fluorides, as we’ve always said, needs to be done carefully. One reason we recommend small amounts of fluoride toothpaste is because we don’t want young children swallowing high levels of fluoride. In that case, though, the concern is fluorosis, not any effect on IQ. But it’s worth remembering that the fluoride concentration in toothpaste is about 1,500 times greater than the concentration in fluoridated drinking water.