by Bonnie C. Dyck, RDH, MPH
From the Past Toward the Year 2000
Community water fluoridation is the deliberate upward adjustment of the natural
trace element fluoride to promote public health through the prevention of dental caries
(tooth decay) in accordance with scientific and dental guidelines. Fluoride is present
naturally in variable amounts in all soils and existing water supplies. It is also present
in animal and plant food consumed by people. The highest concentrations in mammals are
found in the bones and teeth.
- The study of the correlation between fluorides in water and dental health dates back to
the early 1900's, when a young dentist, Frederick S. McKay, established a dental practice
in Colorado Springs, Colorado. In 1908, Dr. McKay initiated a study to investigate the
cause of a developmental enamel defect which he called "Colorado Brown Stain."
We know this defect today as dental fluorosis (mottled enamel), or chronic endemic enamel
fluorosis. In the late 1920's Dr. McKay made another major discovery, namely, that teeth
with mottled enamel were essentially free of dental caries. In 1931, fluoride was
identified as the element in drinking water that not only caused mottled enamel but also
inhibited dental caries. During the 1930's, Dr. H. Trendly, Dean of the U.S. Public Health
Service, and Dr. McKay corroborated to determine if fluoride could be added to the
drinking water to prevent cavities. Dr. Dean and his associates conducted several classic
studies to establish a community fluorosis index. This research led to further studies
that predicted the cause-and-effect relationship between fluoridation and the reduction of
dental caries and that also determined what the optimal levels of fluoride should be in a
community's drinking water (1ppm).
Four Classic Studies
- Although the studies on fluorides were interrupted by World War II, on January 25, 1945,
Grand Rapids, Michigan, became the first city in the world to adjust its water fluoride
concentration to a level expected to reduce dental caries and achieve dental health. Four
and a half months later Newburgh, New York, added sodium fluoride to its water supply; and
in late June, 1945, fluoride was added to the water supply of Brantford, Ontario. In
February, 1947, Evanston, Illinois, was fluoridated. These studies firmly established
fluoridation as a practical and effective public health measure that would prevent dental
- Although it had been determined that fluoridation was safe and effective, the
engineering aspects needed to be developed before community water fluoridation could be
more widely implemented. In the 1950's and 1960's, two more individuals emerged on the
fluoridation scene, both with the U.S. Public Health Service, Franz J. Maier, a sanitary
engineer, and Ervin Bellack, a chemist, helped determine for water fluoridation which
fluoride chemicals were the most practical to use and which were the best mechanical
equipment and process controls to use. In 1963, Maier published the first comprehensive
book of the technical aspects of fluoridation, the Manual of Water Fluoridation
Practices. In 1972, Bellack, then with the U.S. Environmental Protection Agency,
published the Fluoridation Engineering Manual, which is still widely used today.
- The early studies showed that children who had from birth drank water containing optimal
fluoride had 30-60 percent fewer cavities. Current data on dental caries show that the
incidence of dental caries is reduced by 20-40 percent in the mixed dentition of children
(ages 8-12) and 15-35 percent in the permanent dentition of adolescents (ages 14-17).
Fluoridation does not only benefit children, it reduces coronal caries in adults by as
much as 35 percent in fluoridated communities. The benefits of fluoride last a lifetime.
- There is strong evidence that water fluoridation not only makes the tooth more resistant
to bacterial acids, but it inhibits the growth of certain kinds of bacteria that produce
these acids. Fluoride actually promotes the demineralization of the tooth, causing a
reversal process of tooth decay after it has already begun. The actual mechanism for the
incorporation of the fluoride ion in the tooth and bone is not well known. However, it is
known that the fluoride ion replaces the hydroxyl ion (OH-) in the crystal lattice in the
enamel, resulting in a stronger tooth. In addition, several studies have evaluated the
effect of discontinuing water fluoridation; after 2-6 years, the prevalence of dental
caries had risen as high as 84 percent in school-age children, therefore, establishing a
causal relationship between optimal concentrations of fluoride in drinking water and
Community Water Fluoridation
- According to the 1992 Fluoridation Census published by the Centers for Disease Control
and Prevention (CDC), approximately 144 million Americans --- 55.8 percent of the total
U.S. population and 62.1 percent of the population on public water supplies --- are served
by drinking water containing optimal or above levels of fluoride. Despite the benefits of
community water fluoridation, only 14,351 public water systems are fluoridated. In
contrast, approximately 46,000 public water systems, serving more than one-third of the
U.S. population, are not fluoridated. Since the introduction of community water
fluoridation in 1945, the U.S. population receiving the benefits of water fluoridation has
generally grown with the overall population growth and with the growth of the population
on public water systems. One of the oral health objectives contained in Healthy People
2000, which outlines the disease prevention and health promotion objectives for the
nation, proposes to increase to at least 75 percent the proportion of people served by
community water systems providing optimal levels of fluoride. To achieve this goal,
approximately 30 million people must gain access to the benefits of fluoride through the
addition of community water fluoridation to their public water systems.
State Mandate and Ranking
- Fluoridation is mandatory in 8 states: Connecticut (1965), Georgia (1973), Illinois
(1967), Michigan (1968), Minnesota (1967), Nebraska (1973), Ohio (1969), and South Dakota
(1969). Six of these states have restrictions in their laws that limit the scope of the
mandate; however, the two other states, Minnesota and Illinois, have mandated that all
public water supplies be fluoridated. According to the 1992 CDC Fluoridation Census, nine
of the states with the lowest percentage of population on public systems using fluoridated
water are in the western one-third of the country (Washington, Idaho, Wyoming, Montana,
Oregon, Arizona, California, Nevada, and Utah). Other low ranking states include Kansas,
New Hampshire, New Jersey, Mississippi, and Hawaii. Four of the five largest U.S. cities
(New York, Chicago, Philadelphia, and Detroit) were fluoridated between 1950 and 1960. The
fifth, Los Angeles, with a population of 3 million, is not fluoridated. Twenty-one states
meet the Healthy People 2000 objective of having at least 75 percent of their
population on public water supplies that receive the benefits of fluoridated drinking
- Community water fluoridation in the 1990's continues to be a political and legal issue
in the public health arena. From a scientific and public health perspective, community
water fluoridation is not controversial. There is a broad consensus among scientists,
health professionals, and the courts that water fluoridation is safe, cost effective,
practical, equitable, and does not violate individual rights guaranteed in the U.S.
Constitution. Recently, statewide ballots to prohibit fluoridation have surfaced in
Oregon, Washington, and Utah. Also, over the last decade, groups who oppose water
- Made attempts to rescind fluoridation in communities already fluoridated;
- Introduced legislative bills to allow local option for fluoridation in those states with
statewide mandates; and
- Initiated state and local litigations.
- Opponents of fluoridation have used many of the popular phrases that have been alarming
to the public and effective in defeating fluoridation efforts, such as "violation of
personal freedom," "forced medication," "Communist plot," and
"an abuse of 'police power.'" The legal validity of fluoridation has been
repeatedly tested and universally affirmed by the court of last resort in the United
States over the past decade. Over a dozen cases reached the U.S. Supreme Court between
1954 and 1984, but none were actually heard by the court. Either the cases were dismissed
for lack of a substantial federal question, or the court denied the writ of certiorari
for which no reason need be given.
- In 1980, 41 fluoridation referenda were held in the United States; fluoridation was
disapproved in 33 of these and approved in only eight. Between 1977 and 1982, about 25
percent of the ballot measures on fluoridation were approved. Although much progress has
been made in water fluoridation over the last 45 years, it is important that supporters of
fluoridation understand various factors that often result in defeat of fluoridation
efforts. These factors include, but are not limited to:
- Public apathy and distrust in government.
- Failure to effectively educate the public on the scientific and sociopolitical aspects
of water fluoridation.
- Timing and readiness of the community to consider the adoption of fluoridation as a
preventive oral health measure.
- Failure of health professionals to treat the situation as a "political"
- Failure of supporters of fluoridation to organize and prepare countererresponses early
enough to refute opponents claims.
- Failure to word the ballot succinctly to avoid confusion by the voter.
- Fluoridation has been linked with many diseases and conditions (from constipation in
dogs to cancer in humans), none of which has ever shown to be valid.
Toward the Year 2000
- If the year 2000 fluoridation goal is to be met, there must be a collaborative
partnership established at local, state, federal, and national levels to do the following:
- Develop and implement a plan of action to maintain efficacy of water fluoridation as a
proven public health measure.
- Organize and enlist the support of other state and federal organizations that have an
influence in guiding the development of public health policies and bringing about social
- Effectively translate fluoridation information into languages for all racial and ethnic
- Develop new and innovative strategies to meet the challenges of fluoridation opponents,
both past and present.
- Develop a national clearinghouse for fluoridation materials, which include the
sociopolitical, legal, medical, dental, scientific, and engineering aspects of community
- Develop a national surveillance system to collect, analyze, and evaluate risk factor
data related to fluorides.
- Create a national work group charged with the responsibility of developing a strategic
plan to implement a national policy that would require all public water systems serving
more than a population of 50,000 to fluoridate their water supplies.
- Support legislation to fund community water fluoridation.
- Finally, these plans of action must also be accompanied by a consorted effort to
eliminate the general public's misconceptions of water fluoridation in order to ensure the
public's acceptance of water fluoridation as the practical and effective means of
preventing dental caries.
Bonnie C. Dyck, RDH, MPH
Bonnie Dyck received her Diploma of Dental Hygiene from Meharry Medical College in
Nashville, Tennessee and her MPH degree from the University of Tennessee, Knoxville. She
is currently working with the California Department of Health Services, Dental Health
Section, as the state fluoridation coordinator. She is also a public health advisor with
the Centers for Disease Control and Prevention. She conducts a series of fluoridation
seminars during the winter quarter at the University of California, San Francisco, School
- Ripa LW: A half-century of community water fluoridation in the United States: Review and
commentary. J. Public Health Dent 53(1):17-44, 1993.
- Dodge CH, Tiemann ME: Fluoridation of Public Drinking Water: Issues of Health
Benefits and Risks.. Congressional Research Service, Library of Congress. September 1,
- Grembowski D, Fiset L, Spadafora A: How fluoridation affects adult dental caries:
Systemic and topical effects are explored. JADA 123(February):49-54, 1992.
- Newbrun E: Effectiveness of water fluoridation. J Public Health Dent 49(5 Spec
- Kaminsky LS, Mahoney MC, Leah J, et al.: Critical Reviews of Oral Bio Med
- U.S. Public Health Service, Committee to Coordinate Environmental Health and Related
Programs. Ad Hoc Subcommittee on Fluoride: Review of Fluoride Benefits and Risks
Washington, DC, Public Health Service Department and Human Services, 1991.