Water fluoridation controversy
The water fluoridation controversy arises from political, moral, ethical, and safety concerns regarding the fluoridation of public water supplies. While some countries, particularly in Europe, have ceased water fluoridation, the controversy persists in others. Those opposed argue that water fluoridation may cause serious health problems, is not effective enough to justify the costs, and has a dosage that cannot be precisely controlled. In some countries, fluoride is added to table salt.
At the dosage recommended for water fluoridation, the only known adverse effect is dental fluorosis, which can alter the appearance of children's teeth during tooth development. Dental fluorosis is cosmetic and unlikely to represent any other effect on public health. Some countries choose water fluoridation as a method to reduce cavities in both children and adults.
Opposition to fluoridation has existed since its initiation in the 1940s. During the 1950s and 1960s, some opponents of water fluoridation suggested that fluoridation was a communist plot to undermine public health. In recent years water fluoridation has become a pervasive health and political issue in many countries, resulting in changes to public policy regarding water fluoridation.
Many who oppose water fluoridation consider it to be a form of compulsory mass medication.
Water fluoridation was characterized in at least one journal publication as a violation of the Nuremberg Code and the Council of Europe's Biomedical Convention of 1999. A dentistry professor and a philosopher argued in a dentistry journal that the moral status for advocating water fluoridation is "at best indeterminate" and could even be considered immoral. They asserted that it infringes upon autonomy based on uncertain evidence, with possible negative effects. Another journal article suggested applying the precautionary principle to this controversy, which calls for public policy to reflect a conservative approach to minimize risk in the setting where harm is possible (but not necessarily confirmed) and where the science is not settled.
In the United Kingdom, the Green Party opposes mass fluoridation on the grounds that “there is conflicting evidence on the benefits to dental health of this practice and major concerns on the cumulative negative wider health effects of total ingestion levels of fluoride” and that “there are further concerns on the links with the chemical industry that supplies artificial fluoride and the compulsory nature of its addition to drinking water that denies consumers choice”.
In her book 50 Health Scares That Fizzled, Joan Callahan writes that, "For lower-income people with no insurance, fluoridated water (like enriched flour and fortified milk) looks more like a free preventative health measure that a few elitists are trying to take away."
Fluoride can occur naturally in water in concentrations well above recommended levels, which can have several long-term adverse effects, including severe dental fluorosis, skeletal fluorosis, and weakened bones. The World Health Organization recommends a guideline maximum fluoride value of 1.5 mg/L as a level at which fluorosis should be minimal.
Fluoridation has little effect on risk of bone fracture (broken bones); it may result in slightly lower fracture risk than either excessively high levels of fluoridation or no fluoridation. There is no clear association between fluoridation and cancer or deaths due to cancer, both for cancer in general and also specifically for bone cancer and osteosarcoma.
In rare cases improper implementation of water fluoridation can result in overfluoridation that causes outbreaks of acute fluoride poisoning, with symptoms that include nausea, vomiting, and diarrhea. Three such outbreaks were reported in the U.S. between 1991 and 1998, caused by fluoride concentrations as high as 220 mg/L; in the 1992 Alaska outbreak, 262 people became ill and one person died. In 2010, approximately 60 gallons of fluoride were released into the water supply in Asheboro, North Carolina in 90 minutes—an amount that was intended to be released in a 24-hour period.
Like other common water additives such as chlorine, hydrofluosilicic acid and sodium silicofluoride decrease pH and cause a small increase of corrosivity, but this problem is easily addressed by increasing the pH. Although it has been hypothesized that hydrofluosilicic acid and sodium silicofluoride might increase human lead uptake from water, a 2006 statistical analysis did not support concerns that these chemicals cause higher blood lead concentrations in children. Trace levels of arsenic and lead may be present in fluoride compounds added to water, however, concentrations are below measurement limits.
The effect of water fluoridation on the natural environment has been investigated, and no adverse effects have been established. Issues studied have included fluoride concentrations in groundwater and downstream rivers; lawns, gardens, and plants; consumption of plants grown in fluoridated water; air emissions; and equipment noise.
Water fluoridation is effective at reducing cavities in both children and adults. Studies have shown that water fluoridation has led to reductions of 50–60% in childhood cavities; while more recent studies show lower reductions (18–40%), likely due to increasing use of fluoride from other sources, notably toothpaste, and also to the halo effect of food and drink made in fluoridated areas and consumed in unfluoridated ones.
A 2000 systematic review found that water fluoridation was statistically associated with a decreased proportion of children with cavities (the median of mean decreases was 14.6%, the range −5 to 64%), and with a decrease in decayed, missing, and filled primary teeth (the median of mean decreases was 2.25 teeth, the range 0.5–4.4 teeth), which is roughly equivalent to preventing 40% of cavities. The review found that the evidence was of moderate quality: many studies did not attempt to reduce observer bias, control for confounding factors, report variance measures, or use appropriate analysis. Although no major differences between natural and artificial fluoridation were apparent, the evidence was inadequate to reach a conclusion about any differences.
Fluoride is also used to prevent cavities in adults. However, there are fewer studies in adults, and the design of water fluoridation studies in adults is inferior to that of studies of self- or clinically-applied fluoride. A 2007 meta-analysis found that water fluoridation prevented an estimated 27% of cavities in adults (95% confidence interval [CI] 19–34%), about the same fraction as prevented by exposure to any delivery method of fluoride (29% average, 95% CI: 16–42%). A 2002 systematic review found strong evidence that water fluoridation is effective at reducing overall tooth decay in communities.
Most countries in Europe have experienced substantial declines in cavities without the use of water fluoridation. For example, in Finland and Germany, tooth decay rates remained stable or continued to decline after water fluoridation stopped. Fluoridation may be useful in the U.S. because unlike most European countries, the U.S. does not have school-based dental care, many children do not visit a dentist regularly, and for many U.S. children water fluoridation is the prime source of exposure to fluoride. The effectiveness of water fluoridation can vary according to circumstances such as whether preventive dental care is free to all children.
Some studies suggest that fluoridation reduces oral health inequalities between the rich and poor, but the evidence is limited. There is anecdotal but not scientific evidence that fluoride allows more time for dental treatment by slowing the progression of tooth decay, or that it simplifies treatment by causing most cavities to occur in pits and fissures of teeth.
The fluoridation of public water has been hailed by the U.S. Centers for Disease Control as one of the top medical achievements of the 20th century. It is ranked No. 9 on this list ahead of "Recognition of tobacco use as a health hazard."
The American Dental Association calls water fluoridation "one of the safest and most beneficial, cost-effective public health measures for preventing, controlling, and in some cases reversing, tooth decay."
Health Canada supports fluoridation, citing a number of international scientific reviews that indicate "there is no link between any adverse health effects and exposure to fluoride in drinking water at levels that are below the maximum acceptable concentration of 1.5 mg/L."
The World Health Organization says fluoridation is an effective way to prevent tooth decay in poor communities. "In some developed countries, the health and economic benefits of fluoridation may be small, but particularly important in deprived areas, where water fluoridation may be a key factor in reducing inequalities in dental health."
Use throughout the world
Water fluoridation is used in the United States, United Kingdom, Ireland, Canada, and Australia, and a handful of other countries. The following nations previously fluoridated their water, but stopped the practice, with the years when water fluoridation started and stopped in parentheses:
- Federal Republic of Germany (1952–1971)
- Sweden (1952–1971)
- Netherlands (1953–1976)
- Czechoslovakia (1955–1990)
- German Democratic Republic (1959–1990)
- Soviet Union (1960–1990)
- Finland (1959–1993)
- Japan (1952–1972)
- Israel (1981–2014) *Mandatory by law since 2002.
In the United Kingdom a Strategic Health Authority can direct a water company to fluoridate the water supply in an area if it is technically possible. The strategic health authority must consult with the local community and businesses in the affected area. The water company will act as a contractor in any new schemes and cannot refuse to fluoridate the supply.
In areas with complex water sources, water fluoridation is more difficult and more costly. Alternative fluoridation methods have been proposed, and implemented in some parts of the world. The World Health Organization (WHO) is currently assessing the effects of fluoridated toothpaste, milk fluoridation and salt fluoridation in Africa, Asia, and Europe. The WHO supports fluoridation of water in some areas.
The first large fluoridation controversy occurred in Wisconsin in 1950. Fluoridation opponents questioned the ethics, safety, and efficacy of fluoridation. New Zealand was the second country to fluoridate, and similar controversies arose there. Fears about fluoride were likely exacerbated by the reputation of fluoride compounds as insect poisons and by early literature which tended to use terms such as "toxic" and "low grade chronic fluoride poisoning" to describe mottling from consumption of 6 mg/L of fluoride prior to tooth eruption, a level of consumption not expected to occur under controlled fluoridation. When voted upon, the outcomes tend to be negative, and thus fluoridation has had a history of gaining through administrative orders in North America.
Outside North America, water fluoridation was adopted in some European countries, but in the late 1970s and early 1980s, Denmark and Sweden banned fluoridation when government panels found insufficient evidence of safety, and the Netherlands banned water fluoridation when "a group of medical practitioners presented evidence" that it caused negative effects in a percentage of the population.
Communist conspiracy theory (1940s-1960s)
Water fluoridation has frequently been the subject of conspiracy theories. During the "Red Scare" in the United States during the late 1940s and 1950s, and to a lesser extent in the 1960s, activists on the far right of American politics routinely asserted that fluoridation was part of a far-reaching plot to impose a socialist or communist regime. These opponents believed it was "another aspect of President Truman's drive to socialize medicine." They also opposed other public health programs, notably mass vaccination and mental health services. Their views were influenced by opposition to a number of major social and political changes that had happened in recent years: the growth of internationalism, particularly the UN and its programs; the introduction of social welfare provisions, particularly the various programs established by the New Deal; and government efforts to reduce perceived inequalities in the social structure of the United States.
Others asserted the existence of "a Communist plot to deplete the brainpower and sap the strength of a generation of American children". Dr. Charles Bett, a prominent anti-fluoridationist, charged that fluoridation was "better than using the atom bomb because the atom bomb has to be made, has to be transported to the place it is to be set off while poisonous fluorine has been placed right beside the water supplies by the Americans themselves ready to be dumped into the water mains whenever a Communist desires!" Similarly, a right-wing newsletter, the American Capsule News, claimed that "the Soviet General Staff is very happy about it. Anytime they get ready to strike, and their 5th column takes over, there are tons and tons of this poison "standing by" municipal and military water systems ready to be poured in within 15 minutes."
This controversy had a direct impact on local program during the 1950s and 1960s, where referendums on introducing fluoridation were defeated in over a thousand Florida communities. It was not until as late as the 1990s that fluoridated water was consumed by the majority of the population of the United States.
The communist conspiracy argument declined in influence by the mid-1960s, becoming associated in the public mind with irrational fear and paranoia. It was portrayed in Stanley Kubrick's 1964 film Dr. Strangelove, in which the character General Jack D. Ripper initiates a nuclear war in the hope of thwarting a communist plot to "sap and impurify" the "precious bodily fluids" of the American people with fluoridated water. Another satire appeared in the 1967 movie In Like Flint, in which a character's fear of fluoridation is used to indicate that he is insane.
Some anti-fluoridationists claimed that the conspiracy theories were damaging their goals; Dr. Frederick Exner, an anti-fluoridation campaigner in the early 1960s, told a conference: "most people are not prepared to believe that fluoridation is a communist plot, and if you say it is, you are successfully ridiculed by the promoters. It is being done, effectively, every day ... some of the people on our side are the fluoridators' 'fifth column'."
Later conspiracy theories
In 1987, Ian E. Stephens authored a self-published booklet, an extract of which was published in the Australian new age publication Nexus Magazine in 1995. In it he claimed he was told by "Charles Elliot Perkins" that: "Repeated doses of infinitesimal amounts of fluoride will in time reduce an individual's power to resist domination by slowly poisoning and narcotising a certain area of the brain and will thus make him submissive to the will of those who wish to govern him ... Both the Germans and the Russians added sodium fluoride to the drinking water of prisoners of war to make them stupid and docile." These statements have been dismissed by reputable Holocaust historians as untrue, but they are regularly repeated to the present day in conspiracy publications and websites.
In 2004, on the U.S. television program Democracy Now, investigative journalist and author of the book The Fluoride Deception, Christopher Bryson claimed that, “the post-war campaign to fluoridate drinking water was less a public health innovation than a public relations ploy sponsored by industrial users of fluoride—including the government’s nuclear weapons program.”
Water was fluoridated in large parts of the Netherlands from 1960 to 1973, at which point the Supreme Court of the Netherlands declared fluoridation of drinking water unauthorized. The Dutch Court decided that authorities had no legal basis for adding chemicals to drinking water if they did not also improve safety. It was also stated as support that consumers cannot choose a different tap water provider. Drinking water has not been fluoridated in any part of the Netherlands since 1973.
In Ryan v. Attorney General (1965), the Supreme Court of Ireland held that water fluoridation did not infringe the plaintiff's right to bodily integrity. The court found that such a right to bodily integrity did exist, despite the fact that it was not explicitly mentioned in the Constitution of Ireland, thus establishing the doctrine of unenumerated rights in Irish constitutional law.
Fluoridation has been the subject of many court cases wherein activists have sued municipalities, asserting that their rights to consent to medical treatment and due process are infringed by mandatory water fluoridation. Individuals have sued municipalities for a number of illnesses that they believe were caused by fluoridation of the city's water supply. In most of these cases, the courts have held in favor of cities, finding no or only a tenuous connection between health problems and widespread water fluoridation. To date, no federal appellate court or state court of last resort (i.e., state supreme court) has found water fluoridation to be unlawful.
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