Description

Fluoride is a naturally occurring ion of fluorine, an element that is abundant in the Earth's crust. Calcium fluoride and sodium fluoride compounds occur naturally in water (including most surface and ground water supplies) and air. They are also released as polluting byproducts of many industrial processes, such as aluminum, steel and fertilizer manufacturing, coal-burning power plants and glass and cement production. 

Fluoride has been embraced by the medical community and public agencies for its ability to prevent tooth decay. In addition to fluoride toothpastes and supplements, fluoride has been added to the municipal drinking-water supplies of nearly two-thirds of the U.S. population. Safety concerns have made fluoridation of water a controversial topic in some areas of the country.

While low doses of fluoride does protect enamel, fluoride can be toxic at high doses. In fact, fluoride toothpaste tubes bear warnings to avoid ingestion. Overexposure in children has been linked to dental fluorosis, in which teeth are permanently stained or pitted. Excessive fluoride ingestion may also cause bone fragility and tenderness.

Current research does not provide evidence of a link between fluoride and cancer.  However, the data has not been sufficient for cancer agencies to make a determination of fluoride’s status as a carcinogen.

The U.S. Environmental Protection Agency, which regulates fluoride levels in water supplies, has set a legal limit of 4 milligrams of fluoride per liter of water (mg/l), warning that some people who drink water containing fluoride in excess of this level over many years could develop bone disease. EPA has also recommended (but does not require) a lower limit of 2 mg/L to protect against dental fluorosis, and advises that children under nine should not drink water that has more than 2 mg/L of fluoride.

A number of towns and cities have resisted fluoridation, including Newark, NJ, Honolulu, HI and Worcester, MA. Nevertheless, the American Dental Association and the EPA maintain that fluoridated water is safe.  Currently, the National Research Council is undertaking a review of the data on fluoride.

In addition to toothpastes, fluoride supplements, and fluoridated drinking water, children ingest fluoride in infant formula and beverages made with fluoridated water.  Fluoride may also be present in foods grown in soil containing fluoride or irrigated with fluoridated water and in milk from cows raised on fluoride-containing water and feed. (EHP)

To avoid excessive exposure for children under the age of nine, consider using a non-fluoridated toothpaste if your drinking water is fluoridated.  Very young children should not be given fluoride toothpaste, as they are likely to swallow it.

Health Effects

Immediate Health Effects

• If SWALLOWED, fluoride is Highly Toxic

• If ABSORBED THROUGH SKIN, fluoride is Not Available

• If INHALED (SNIFFED OR BREATHED IN), fluoride is Not Available

Longterm or Delayed Health Effects

• This chemical is considered an Unclassifiable Carcinogen by the World Health Organization, the U.S. Environmental Protection Agency, or another agency.

Other

• Children who ingest fluoride during the years when the enamel of their permanent teeth is still forming (up to 6-8 years of age) may develop dental fluorosis, a condition in which permanent teeth are irreversibly mottled and stained. National surveys indicate that as many as 22 percent of U.S. children have fluorosis, with even higher rates in some areas with fluoridated drinking water. (EHP)

• Ingesting elevated levels of fluoride over many years may cause fluoride to accumulate in the bones, leading to skeletal fluorosis, in which bones become brittle and tender. (EPA, Hileman, WHO)

• New research suggests that low levels of fluoride may have developmental effects and effects on the brain.

• Decreased rates of tooth decay (dental caries).

For More information

Books, articles, factsheets and reports

Other government agencies

National Library of Medicine's Household Products Database

Lists brands of products that contain fluoride.

http://householdproducts.nlm.nih.gov/

U.S. Environmental Protection Agency

Office of Ground Water and Drinking Water

http://www.epa.gov/safewater/

U.S. Centers For Disease Control and Prevention

Fluoridation Fact Sheets