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Top rated, 2004-2006

At EWG, our team of scientists, engineers, policy experts, lawyers and computer programmers pores over government data, legal documents, scientific studies and our own laboratory tests to expose threats to your health and the environment, and to find solutions. Our research brings to light unsettling facts that you have a right to know.

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fluoride (f)

In the chemical families: Fluoride compounds, Inorganic ions

Fluoride, the ionic form of the element fluorine, has been added to community drinking water supplies since the 1940s to help prevent tooth decay. According to the U.S. Centers for Disease Control, about 184 million Americans -- nearly 70 percent of the U.S. population -- drink fluoridated water.

Over-exposure to fluoride can be toxic, causing fluorosis (mottling and loss of tooth enamel) and skeletal fluorosis (joint pain and stiffness and bone fractures). Some studies point to a possible link between fluoride exposure and osteosarcoma, bone cancer.

The Environmental Working Group supports the use of fluoride in toothpaste, where there is strong evidence of its effectiveness. But EWG’s analysis concludes that fluoridation of public water supplies should stop, because risks outweigh possible benefits, especially for infants and young children who consume more water than adults, relative to their size.

An August 2007 EWG analysis, Fluoride in Southern California Tap Water, warned that the Southern California’s Metropolitan Water District plan to fluoridate drinking water would expose more than 64,000 children to unsafe fluoride levels. The numbers of children at risk will grow if the Environmental Protection Agency follows a 2006 recommendation by the influential National Research Council to lower the legal fluoride level in drinking water.

Scientists are exploring whether childhood exposure to fluoride may cause osteosarcoma, a rare bone cancer. In June 2005, EWG executive director Richard Wiles urged the National Toxicology Program to add fluoride in tap water to its biennial Report on Carcinogens. Wiles cited research by Dr. Elise B. Bassin, whose 2001 Harvard doctoral thesis reported that boys who drank fluoridated water were five times more likely to develop osteosarcoma than those who drank unfluoridated water.

A side controversy developed when EWG discovered that Bassin’s doctoral advisor -- Dr. Chester Douglass of the Harvard School of Dental Medicine -- had omitted her striking results from his final report while conducting research on fluoride exposure and osteosarcoma on grants from the National Institutes of Environmental Health Sciences. Douglass’s claim that no relationship between fluoride and cancer had been observed, coupled with his financial relationship with fluoride toothpaste manufacturer Colgate-Palmolive, led EWG to file ethics complaints with NIEHS and Harvard. Douglass was subsequently cleared of “intentionally” suppressing Bassin’s findings.

In February 2008, EWG asked the Federal Trade Commission to stop Nursery Water, one of the nation’s biggest infant bottled water companies, from advertising that its fluoridated water is safe for babies, in violation of Federal Food and Drug Administration rules and American Academy of Pediatrics guidance.

For more information, contact the Fluoride Action Network.

Health Effects related to fluoride (f): Birth or developmental effects, Brain and nervous system, Organ system toxicity (non-reproductive), Reproduction and fertility

Routes of Exposure related to fluoride (f):

  • Environment: agriculture
  • Food: pesticide residue
  • Water: bottled water, sewage sludge, tap water additive

More chemicals in Fluoride compounds: sodium fluoride, magnesium fluoride, calcium fluoride, view all...

More chemicals in Inorganic ions: iodide, bicarbonate, view all...