Fluoridation is the controlled addition of fluoride salts to a water supply in order to reduce the incidence of tooth decay in those who drink from it. Fluoridated water prevents tooth decay by regenerating enamel damaged by plaque, resulting in a more acid-resistant surface. The World Health Organization (WHO) recommends drinking water fluoride concentrations between 0.5 and 1.0 mg/L depending on climate conditions. Fluoride in varying concentrations occurs naturally in most water sources. Over-fluoridated water can cause dental fluorosis, a cosmetic brown discoloration of the enamel, and skeletal fluorosis, an affliction that can cause pain and damage to the bones and joints, when consumed at concentrations above recommended levels; such levels occur naturally in some water sources. Higher fluoride concentrations uncommon to natural water sources can result in acute fluoride poisoning, as in three cases of improper implementation reported in the US from 1991 to 1998.
Fluoridation was first introduced in the United States in the 1950’s, starting in selected test communities before spreading nationwide. Opposition was quick to follow. Though 50 million Americans had access to fluoridated water by 1960 and 170 million had access by 2002, opposition remained strong, with minor and major victories across the country. Internationally, fluoridation was adopted in Australia and Ireland within the decade, eventually outpacing the United States in implementation. Other countries such as New Zealand, Brazil, and the United Kingdom also adopted water fluoridation in the same decade. The efficacy of fluoridation in the modern era is questioned, with some studies suggesting that access to alternative fluoride sources renders water fluoridation unnecessary.
The history of fluoridation began in 1901 with Frederick McKay, a dentist in Colorado Springs, CO. McKay's work revolved around finding the cause of "Colorado brown stain," a discoloration of the teeth common in and around the Rocky Mountains. His studies conducted in Colorado were inconclusive. Thirty years after he began his search, in 1931, a breakthrough in Bauxite, Arkansas showed that a change in the drinking water was the culprit of a recent outbreak. He also noted, without fully realizing the implications, that teeth with the stain had "a singular absence of decay". Further testing by ALCOA, an aluminium company with a vested interest in the area, showed high levels of fluoride in the water. By 1942, it was shown by studies funded by the U.S. Public Health Service (USPHS) that at concentrations of one part-per-million (ppm), the health benefits of fluoridated water were retained without visible staining of the teeth.  The USPHS noted that the addition of fluoride to public water sources appeared to drastically improve dental health, but cautioned against implementation without testing of the long-term effects.
Three years later, case studies for water fluoridation began in four cities: Grand Rapids, MI, Newburgh, NY, Sheboygan, WI, and Marshall, TX. Fluoride was added to the water at one ppm in each city to be compared to three control cities over a ten to fifteen year period. If fluoridation proved safe and effective at the end of these studies, the USPHS would push for implementation in more communities. Within a year, however, pressure arose in Wisconsin from progressives for a more aggressive approach, pushing for fluoridation in 50 Wisconsin communities by 1950 and urging other states to follow suit. This campaigning combined with positive initial reports from the case study cities led the USPHS to change its stance from a conservative approach to immediate fluoridation in every community in America. The American Dental Association (ADA) and American Medical Association (AMA) quickly followed suit.
In 1950, the first major opposition to fluoridation arose in one of the WI progressives' 50 communities, the small town of Stevens Point, WI. The city council's first fluoridation proposal was turned down, and a later referendum confirmed the decision not to fluoridate. This victory for anti-fluoridation was highly publicized, influencing the spread of anti-fluoridation sentiment to parties such as the Citizens Medical Reference Bureau and Prevention magazine. Similar opposition occurred in small towns across the US afterwards, as well as some larger cities such as Los Angeles and Seattle.
The participants of the fluoridation controversy are broad and varied. Proponents generally support fluoridation for the dental health benefits. The World Health Organization (WHO), the Center for Disease Control (CDC), and the Surgeon General have all expressed explicit support of fluoridation of municipal drinking supplies   . Individual citizens concerned about their, or their children’s, health represent both unorganized and organized participants. Unorganized participants also include citizens who are unaware of the fluoridation status of their drinking water, or unaware of fluoridation practices in general. Grassroots organizations both for, and against fluoridation have sprung up all around the country since the controversy first began . . Participants who oppose fluoridation are diverse. Some groups reject fluoridation on the grounds of personal freedom – generally these groups value personal privacy, and object to over-regulation by government. In fact, some groups have even claimed fluoridation of drinking water was a government tool for mind control.
Perhaps the biggest group to oppose fluoridation is citizens concerned about health; these participants cite fluoride as a toxic chemical and unnatural additive to public water. Alternative medicine supporters and smaller religious groups also reject mass fluoridation. A small subset of the health opposition is simply concerned with over-fluoridation in the form of dental fluorosis or fluoride poisoning. Other organized participants include contractors involved in installing, maintaining, and improving municipal fluoridation systems. These groups, as well as fluoride manufacturers and distributors, have a vested interested in large scale adoption of fluorinated water supplies. On the other side of industry, companies that sell products containing fluoride for health purposes (e.g. toothpaste with added fluoride) stand to lose market share if municipal water supplies were to be fluorinated.
The anti-fluoridation campaign in Stevens Point, WI was led by Alexander Wallace, a concerned citizen and local poet. His efforts forced a referendum for fluoridation in the town; however, before the referendum was carried out, the city council secretly voted to add fluoride anyways. When Wallace discovered this decision, he used it to further fuel his efforts, suggesting that the groups pushing fluoridation in Stevens Point were looking to experiment on the citizens of the town. His use of populist tactics such as mass meetings and handbills calling citizens to action resulted in the ultimate success of his campaign: fluoridation in Stevens Point was rejected by referendum. This success was publicized nationally, and demonstrated to opponents of fluoridation that an organized, properly executed campaign could be successful in overturning fluoridation, even when the pro-fluoridation group had experts on their side. The success at Steven's point was picked up by anti-communist groups such as the publishers of The Dan Smoot Report and the John Birch Society, who framed fluoridation as a result of communist infiltration into the government; these groups suggested that fluoridation was a communist plot to give drugs to the entire American population.
Another prominent event in the 1950's which fueled popular anti-fluoridation opinion in the US was a study by Texas biochemist Dr. Alfred Taylor. His study concluded that sodium fluoride, the most common salt used to fluoridate water, caused cancer to occur sooner (but not more frequently) in laboratory mice. This study was later to be found faulty after review by the US Public Health service, but the results still prevented the implementation of fluoridation in over 20 Texas towns, including Austin, Dallas, and Fort Worth.
Other groups historically associated with opposition to fluoridation are natural food activists, chiropractors, and Christian Scientists. The combination of these groups influences led to the denial of a proposal to implement fluoridation in Seattle, WA in 1951. Another significant figure in the anti-fluoridation was John Y. Yiamouyiannis, former science director of the National Health Federation, an alternative medicine organization. His studies in Los Angeles, dismissed by the CDC, National Cancer Institute, and National Academy of Science as insubstantial, nevertheless influenced the public and policymakers enough to defeat a fluoridation proposal in 1975.
Currently, fluoridation is widespread in the United States, Malaysia, Singapore, Australia, New Zealand, Brazil, Chile, and the Republic of Ireland. Many western European nations, including Austria, Denmark, Finland, the Netherlands, and Sweden, do not fluoridate their water at all; others, such as Germany, Portugal, Spain and the United Kingdom, have some level of fluoridation. Currently over 144 cities in United States are also without fluoridated municipal drinking water. Globally, only 5.7% of the population has access to water with recommended levels of fluorine. Fluoridation is rare in Europe, with only 2% of Europeans having access to fluoridated water; instead European countries promote use of alternative sources. Many of the successful tactics used in the historical fight can be easily seen in use by modern day anti-fluoridation groups. The unification of unorganized participants into integrated, active networks continues to be the most successful strategy. Today, these groups in the US generally attempt to argue against fluoridation on the basis of toxicity, individual rights, or forced medication. A common argument from modern opponents of fluoridation is the proliferation of alternatives such as fluoride toothpaste and their effectiveness in regions without artificially fluoridated water.
Fluoride naturally occurs in groundwater and in crops. Drinking water, however, is usually the largest contributor to daily fluoride intake. In fact, almost all water contains fluoride – though generally not enough to produce the desired health effects seen with artificially fluoridated drinking supplies. The fluoride concentration of groundwater varies with geography; water with high fluoride content are mostly found in calcium deficient groundwater. Large parts of Africa, China, the Middle East, and southern Asia are known to contain relatively high concentrations of fluoride. The United States, too, has similar geographical areas of naturally high fluoride concentration in the water supply.
In addition to naturally occurring fluoride in food and water, fluoride has been added to commercial products with the intention of improving dental health. Toothpaste and mouthwash are some of the most common commercial products to increase the daily fluoride intake. Fluoride supplements or professional dental fluoride treatments can also provide forms of natural or synthetic fluoride. In some counties with limited naturally occurring fluoride or fluoridated drinking supplies, salt has been fortified with fluoride to provide improved dental health. All of these products require conscious and consistent application or use, appealing to those who recognize the health benefits of fluoride but believe fluoridation of public water supply to be immoral on the grounds of enforced medication.
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