IDPH 125th


A group of city officials met on Feb. 23, 1945, to consider adding sodium fluoride to Evanston’s public water supply to prevent dental caries, particularly in children. The decision was to begin fluoridation of the public water supply on an experimental basis. A month later, the Department agreed to subsidize the project.

Fluoridation of the water supply, which has been shown to reduce dental caries in children by almost two-thirds, began in Evanston in 1947. It was preceded by a survey of prevailing dental conditions among children in Evanston and nearby Oak Park. Periodic follow- up surveys done during the experimental period revealed a substantial reduction in carious teeth compared with conditions that existed prior to fluoridation in Evanston and Oak Park, where the water supply was free of fluorine.

On Aug. 8, 1951, the Department adopted a policy favoring fluoridation and launched an aggressive program to promote its use by all public water supply systems in Illinois. In December of that year, Chester, in Randolph County, became the second Illinois community to fluoridate its water supply. During 1952, other communities followed: Beckemeyer, Carbondale, Carlyle, Casey, De Soto, Northfield, Orion, Park Forest, Waukegan and Winnetka.

Strong and sometimes bitter opposition to fluoridating public water supplies developed in many communities and the proposition was defeated in several local referenda. Despite a well organized effort by opponents of fluoridation, however, 148 municipalities (including Chicago), representing nearly 5.3 million people, had begun to treat their public water supplies by the end of 1962.

Mandatory fluoridation of all Illinois public water supplies was first considered in February 1966, during a meeting in Chicago on dental health education. Several months later – on Aug. 4, 1966 – representatives from the Illinois Department of Public Health and from the Illinois State Dental Society met to consider plans for adopting such a program.

Legislation mandating the fluoridation of all public water supplies in the state was passed in 1967 and signed into law July 18 of that year. The law gave communities one year in which to submit plans and to begin actual fluoridation. Approximately 6 million Illinois residents were already drinking water with natural or added fluoride prior to the July 1, 1968, deadline.

Community water fluoridation is still the most equitable and cost effective public health measure to protect teeth from decay and to improve oral health for both children and adults. Studies have shown that, for every dollar invested in fluoridation, as much as $38 is saved in dental treatment costs.

Fluoride is found naturally in water but, in many communities, the amount of the mineral is too low and does not meet the required standards. When this occurs, fluoride must be added to the water to provide optimal oral health benefits to the community. Of the 1,804 water supply systems in Illinois, 860 add fluoride to their water. The average cost to fluoridate a community water supply is about 50 cents per person per year.

The Department, along with the Illinois Environmental Protection Agency, annually recognize water systems for maintaining the state mandated fluoride level in drinking water. Illinois maintains required fluoride levels for 93 percent of those residents served by its public water systems. The current national average is 66 percent.

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Springfield, Illinois 62761
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