Consumers hearing that some U.S. communities will no longer add fluoride to their drinking water, such as Florida’s Pinellas County, may wonder whether this cavity fighter is safe.
The short answer: Most health professionals say yes, as long as people don’t ingest too much of it.
Studies in the 1930s found tooth decay was less severe in areas with more fluoride in drinking water, prompting U.S. communities to add it to their water.
Yet the Obama administration is moving to lower its recommended amount in drinking water as newer research shows high levels can cause tooth and bone damage.
The National Academies’ National Research Council found in 2006 that children are at risk of losing enamel and developing pits and brown stains on their teeth if the fluoride in their water exceeds the maximum level set by the U.S. Environmental Protection Agency. It said this “severe fluorosis” can cause tooth decay.
The report also found that people who drink water with fluoride at that maximum level — 4 milligrams per liter — over a lifetime appear at increased risk for bone fractures.
About 200,000 Americans live in areas that exceed EPA’s maximum level, and 1.4 million live where drinking water contains at least 2 milligrams of fluoride per liter — an amount that can cause tooth spotting, according to the report.
“It can be either faint lines, like striations, or discreet white spots,” says William Bailey, chief dental officer of the U.S. Public Health Service. “Most people don’t know they have it.”
Bailey says this tooth spotting has been increasing in the USA, especially among adolescents ages 12 to 15. Forty-one percent had some form of fluorosis in a 1999-2004 survey by the U.S. Centers for Disease Control and Prevention. That’s up from 23% in a 1986-1987 survey.
In January, the EPA announced that it would review its maximum allowable level, and the Department of Health and Human Services said it would recommend that fluoride be set at the lowest end of its current range, which is 0.7 to 1.2 milligrams of fluoride per liter.
Bailey says he expects HHS to finalize its 0.7 recommendation by the end of this year.
HHS’ level looks at the total amount of fluoride in drinking water, some of which occurs naturally or is caused by industrial pollution.
“Ideally, we’d like everybody to be at 0.7,” says Howard Pollick, a practicing dentist and spokesman for the American Dental Association, which supports the lowering of the optimal amount.
But many small water systems, he says, have naturally occurring fluoride above that level and would find it costly to either pipe water in from elsewhere or defluoridate their supply.
Sonya Lunder, a senior analyst at the Environmental Working Group, a Washington-based advocacy group, says people now get enough fluoride from toothpaste and other dental products.
Lunder says: “You don’t need to swallow fluoride to get its benefits.”