This is a fact sheet about a chemical that may be found in some public or
private drinking water supplies. It may cause health problems if found
in amounts greater than the health standard set by the United States
Environmental Protection Agency (EPA).
August 2001—The Centers for Disease Control and Prevention (CDC) has issued new recommendations
on using fluoride to prevent dental caries (tooth decay). The recommendations provide guidance to
health care providers, public health officials, policymakers, and the general public on how to achieve
maximum dental decay protection while efficiently using dental care resources and minimizing any cosmetic
concerns. In 1999, CDC profiled the wide-spread practice of fluoridating community drinking water to
prevent dental decay as one of 10 great public health achievements of the 20th Century.
Fluorine, from which fluoride is derived, is the 13th most abundant element and is released into the
environment naturally in both water and air.
Fluoride is naturally present in all water. Community water fluoridation is the addition of fluoride to adjust the natural fluoride concentration of a community’s water supply to the level recommended for optimal dental health, approximately 1.0 ppm (parts per million). One ppm is the equivalent of 1 mg/L, or 1 inch in 16 miles.
Community water fluoridation is an effective, safe, and inexpensive way to prevent tooth decay.
Fluoridation benefits Americans of all ages and socioeconomic status.
Children and adults who are at low risk of dental decay can stay cavity-free through frequent exposure to
small amounts of fluoride. This is best gained by drinking fluoridated water and using a fluoride toothpaste twice daily.
Children and adults at high risk of dental decay may benefit from using additional fluoride products,
including dietary supplements (for children who do not have adequate levels of fluoride in their
drinking water), mouthrinses, and professionally applied gels and varnishes.
Good scientific evidence supports the use of community water fluoridation and the use of fluoride
dental products for preventing tooth decay for both children and adults.
Fluoride was first used purposefully to prevent tooth decay in Grand Rapids, Michigan, in 1945 by
adjusting the level of fluoride in drinking water. Fluoridation of drinking water has been used
successfully in the United States for more than 50 years.
Fluoridation of community water has been credited with reducing tooth decay by 50%-60% in the United
States since World War II. More recent estimates of this effect show decay reduction at 18%-40%, which
reflects that even in communities that are not optimally fluoridated, people are receiving some benefits
from other sources (e.g., bottled beverages, toothpaste).
Fluoride’s main effect occurs after the tooth has erupted above the gum. This topical effect happens
when small amounts of fluoride are maintained in the mouth in saliva and dental plaque (the film that adheres to tooth enamel).
Fluoride works by stopping or even reversing the tooth decay process. It keeps the tooth enamel strong
and solid by preventing the loss of (and enhancing the reattachment of) important minerals from the tooth enamel.
Of the 50 largest cities in the United States, 43 have community water fluoridation.
Fluoridation reaches 62% of the population on public water supplies—more than 144 million people.
(These data are from the Water Fluoridation Fact Sheet, 1992. See more recent data in the Water
Fluoridation Fact Sheet, 2000).
Water fluoridation costs, on average, 72 cents per person per year in U.S. communities (1999 dollars).
Consumption of fluids—water, soft drinks, and juice—accounts for approximately 75 percent of fluoride
intake in the United States.
Children aged 6 years or less may develop enamel fluorosis if they ingest more fluoride than needed. Enamel
fluorosis is a chalk-like discoloration (white spots) of tooth enamel. A common source of extra fluoride is
unsupervised use of toothpaste in very young children.
Fluoride also benefits adults, decreasing the risk of cavities at the root surface as well as the enamel crown.
Use of fluoridated water and fluoride dental products will help people maintain oral health and keep more permanent teeth.
Many communities add fluoride to their drinking water to promote dental health.
Each community makes its own decision about whether or not to add fluoride. EPA has set an
enforceable drinking water standard for fluoride of 4 mg/L (some people who drink water
containing fluoride in excess of this level over many years could get bone disease, including
pain and tenderness of the bones). EPA has also set a secondary fluoride standard of 2 mg/L to
protect against dental fluorosis. Dental fluorosis, in its moderate or severe forms, may result
in a brown staining and/or pitting of the permanent teeth. This problem occurs only in developing
teeth, before they erupt from the gums. Children under nine should not drink water that has more
than 2 mg/L of fluoride.
Note: This fact sheet is part of a larger
publication adapted from U.S. EPA publication: EPA National Primary
Drinking Water Regulations.