Fluoridation (Encyclopedia of Environmental Issues, Revised Edition)
Fluoridation of water supplies was first introduced in the United States in the 1940’s as a preventive measure to reduce tooth decay, which was a serious and widespread problem in the early twentieth century. Since that time, many cities have taken the step of adding fluoride to their public water-supply systems, but the merits and drawbacks of fluoridation have long been subjects of debate. Proponents of fluoridation claim that it has dramatically reduced tooth decay in Americans, but opponents of the practice have not been entirely convinced of its effectiveness, and some are concerned about possible health risks that may be associated with fluoridation. The decision to fluoridate drinking water generally rests with local governments and communities.
Fluoride is the water-soluble, ionic form of the element fluorine. It is present naturally in most water supplies at low levels, generally less than 0.2 part per million (ppm), and nearly all food contains traces of fluoride. Tea contains more fluoride than most foods, and fish and vegetables also have relatively high levels. The findings of many scientific studies suggest that water containing a concentration of about 1 ppm fluoride, in contrast with water containing less fluoride, dramatically reduces the incidence of tooth decay.
Tooth decay occurs when acids in the mouth dissolve the protective enamel outer coating of a tooth, creating a hole, or cavity. These acids are present...
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Opposition to Fluoridation (Encyclopedia of Environmental Issues, Revised Edition)
Strong opposition to fluoridation began to emerge in the 1950’s, as some people asserted that the possible side effects of consuming fluoride had not been adequately investigated. This concern was not unreasonable, given that high levels of ingested fluoride can be lethal. It is not unusual, however, for a substance that is lethal at high concentration to be safe at low levels, as is the case with most vitamins and trace elements. Opponents of fluoridation were also concerned on moral grounds; they argued that fluoridation represents compulsory mass medication.
Since the 1960’s, heated debates have arisen over the issue of fluoridation across the United States. Critics have pointed to the harmful effects of large doses of fluoride, including bone damage, and the special risks fluoride may pose for some people, such as those with kidney disease and others who are particularly sensitive to toxic substances. Between the 1950’s and the 1980’s, some scientists suggested that fluoride may have a mutagenic effect—that is, it may be associated with human birth defects, including Down syndrome.
Controversial claims that fluoride can cause cancer were also raised in the 1970’s, most notably by biochemist John Yiamouyiannis, who asserted that U.S. cities with fluoridated water had higher rates of death from cancers than did cities with unfluoridated water. Fluoridation proponents were quick to discredit his...
(The entire section is 688 words.)
Further Reading (Encyclopedia of Environmental Issues, Revised Edition)
De Zuane, John. Handbook of Drinking Water Quality. 2d ed. New York: John Wiley & Sons, 1997.
Martin, Brian. Scientific Knowledge in Controversy: The Social Dynamic of the Fluoridation Debate. Albany: State University of New York Press, 1991.
National Research Council. Health Effects of Ingested Fluoride. Washington, D.C.: National Academy Press, 1993.
Reilly, Gretchen Ann. “The Task Is a Political One: The Promotion of Fluoridation.” In Silent Victories: The History and Practice of Public Health in Twentieth-Century America, edited by John W. Ward and Christian Warren. New York: Oxford University Press, 2007.
Stewart, John Cary. Drinking Water Hazards. Hiram, Ohio: Envirographics, 1989.
Weinstein, L. H., and A. W. Davison. Fluorides in the Environment. Cambridge, Mass.: CABI, 2004.
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Fluoridation (Encyclopedia of Science)
Fluoridation is the process of adding the chemical fluoride to a substance (often drinking water) to reduce tooth decay. In the human body, fluoride acts to prevent tooth decay by strengthening tooth enamel and inhibiting the growth of plaque-forming bacteria. Fluoridation was first introduced into the United States in the 1940s in an attempt to study its effect on the reduction of tooth decay. Since then many cities have added fluoride to their water supply systems.
Early fluoridation studies
In 1901, Frederick McKay (1874959), a dentist in Colorado Springs, Colorado, noticed that many of his patients had brown stains, called mottled enamel, on their teeth. After studying the cause of this staining for three decades, McKay concluded that it was due to high concentrations of fluoride in the patients' drinking water. McKay also observed that although unsightly, the stained teeth of his patients seemed to be more resistant to decay. After experimentation, he found that the ideal level of fluoride in water should be one part fluoride per million parts of water (or one ppm). That was enough to stop decay but too little to cause mottling.
The U.S. Public Health Service (USPHS) grew interested in fluoride and, following safety tests on animals, conducted field tests. In 1945, the public water systems of Newburgh, New York, and Grand Rapids, Michigan,...
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Fluoridation (Encyclopedia of Children's Health)
Fluoridation is the addition of fluoride to water supplies to help prevent tooth decay.
The element fluorine is the seventeenth most abundant element in the earth's crust. It occurs as fluoride ion in combination with other elements such as sodium. Most water supplies naturally contain low levels of fluoride. In much of the United States, as well as in other parts of the world, fluoride is added to community water systems to bring fluoride levels up to the recommended amount for preventing teeth decay: 0.7.2 parts of fluoride to 1 million parts of water (parts per million or ppm). The levels of naturally occurring fluoride in fresh water range from less than 0.1 ppm to more than 13 ppm. Seawater contains about 1.5 ppm. As of 2000, about 162 million Americanswo-thirds of the populationere served by fluoridated water systems.
Mode of action
Systemic fluorides, including fluoridated water and prescription fluoride supplements supplied as tablets, drops, or lozenges, can be incorporated into the enamel of children's developing teeth. The enamel that covers the crown, the part of the tooth that is above the gum, is made of a substance...
(The entire section is 2496 words.)