Fluoride Action Network

Researchers pour dose of worry in fluoridated water

Source: Chicago Tribune | Tribune Health & Fitness Reporter
Posted on April 2nd, 2006

Fluoride is considered an essential weapon against rotting teeth, but it also can make bones brittle. In addition, researchers suspect that the controversial substance can cause a rare bone and joint disease called skeletal fluorosis and even lower a person’s IQ.

So why have Chicago and many other communities been adding fluoride to tap water since the 1950s?

As with most chemicals, the dose makes the poison, according to a recent report by the prestigious National Academy of Sciences.

After studying the hotly debated issue for three years, the panel of scientists found that the U.S. Environmental Protection Agency’s standard for the maximum amount of naturally occurring fluoride allowed in drinking water–4 milligrams of fluoride per liter of water–is too high. About 200,000 people in the U.S., including the western Illinois town of Bushnell and parts of Indiana, Colorado and New Mexico, consume water with naturally occurring fluoride levels of 4 milligrams per liter or higher.

At this level, children are at greater risk of tooth-enamel fluorosis, which shows up as yellow and brown staining, enamel loss and pitted teeth. A majority of the committee found that people who consume water containing that much fluoride over a lifetime are likely to have increased risk of bone fractures.

Still, the American Dental Association, which considers fluoride as sacred as a childhood vaccination, pointed out that the study did not examine the health risks or benefits of the artificially fluoridated tap water that about two-thirds of all Americans drink. This treated water is safe, they say, because it contains just 0.7 to 1.2 milligrams per liter of water, which is far below the too-high 4-milligram cap set by the EPA.

Most medical experts agree that in small amounts, fluoride is a safe, effective and cheap way to prevent tooth decay. The Centers for Disease Control and Prevention hails community fluoridation as one of the top 10 public health achievements in the 20th Century.

But while the anti-fluoride camp once was viewed skeptically as a small but vocal fringe group that distributed dangerous misinformation, the NAS report shows that there are legitimate concerns with high levels of fluoride.

Although drinking water presents the greatest exposure to fluoride, there is still a debate over whether fluoride needs to be swallowed to be effective. And the evidence regarding fluoride’s potential to cause cancer, particularly of the bone, is tentative and mixed, the NAS committee found.

Another study that looks at osteosarcoma and fluoride exposure–one that may help understand fluoride’s carcinogenic potential–is under way at the Harvard School of Dental Medicine and is expected to be published this summer. Meanwhile, consumers can take steps to make sure the cumulative intake of fluoride remains at a safe level.

Find out how much fluoride is in your drinking water. In 1947, Evanston became the first Illinois community to fluoridate water. Now 860 of the 1,804 water systems in the state add fluoride, according to the Illinois Department of Public Health. Check whether yours does by calling the local water-treatment provider. Water-quality reports, called consumer-confidence reports, provide a summary of what’s in the water in your area. If you’re living in a treated area, you don’t need supplements such as chewable fluoride tablets.

Monitor your child’s intake. Because of their low body weight, infants and young children are exposed to three to four times as much fluoride as adults, according to the study. Don’t give children fluoridated toothpaste until they can safely spit it out. Fluoride is also in food and water-based products and bottled water marketed to kids.

Use fluoride-free bottled water to mix infant formula. For children under 6 months of age, the upper limit of daily fluoride is 0.7 milligrams per liter. But in most major cities, at least 15 percent of formula-fed infants are exposed to excessive levels of fluoride, mostly from tap water used to make infant formula, according to the Environmental Working Group.

Monitor your own intake. If you drink a lot of water because of exercise, outdoor work or a medical condition, you might be exposed to more fluoride than you realize. Fluoride accumulates in bone over time, so the elderly and people with severe renal deficiency who have trouble excreting fluoride in their urine are likely to have increased bone-fluoride concentrations.