Water fluoridation
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Water fluoridation is the practice of adding fluoride compounds to water with the intended purpose of reducing tooth decay in the general population. Many North American and Australian municipalities fluoridate their water supplies in the belief that this practice will reduce tooth decay at a low cost. Currently 66% of United States residents on public water supplies have fluoridated water.<ref>http://www.awwa.org/Advocacy/pressroom/fluoride.cfm</ref>
Water purveyors typically add a fluoride in the form of sodium hexafluosilicate or hexafluosilicic acid <ref>Reeves T.G.: "Technical aspects of water fluoridation in the United States and an overview of fluoridation engineering world-wide", Community Dent. Health 13: Suppl. 2 (1996) 21-26. </ref> <ref>Bellack E.: "Fluoridation Engineering Manual", Report EPA-520/9-74-022, (1974). </ref>, at a level between 0.7 and 1.2 ppm. These compounds originate as side products from the processing ("defluorination") of phosphate ores to prepare fertilizer, food additive etc. <ref>Bellack E., Baker R.J. (USPHS): "Fluoridation Chemicals - the supply picture", J. Am. Water Works Assn. 62 (1970) 223 </ref> <ref>Maier F.J. (USPHS): "Manual of Water Fluoridation Practice", McGraw Hill Book Co., New York 1963 </ref>. Fluorides such as sodium fluoride (NaF), sodium monofluorophosphate ("SMFP" or "MFP", Na2FPO3), tin(II) fluoride ("Stannous fluoride", SnF2), and amine fluorides are common ingredients in toothpaste.
Water fluoridation has provoked controversy though opponents of fluoridation have not assembled as a majority in the scientific community. Whether for health concerns or concerns of consent or because their people are receiving fluoride through other means, some governments have ceased or decided not to start fluoridating their water.
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[edit] History
While the use of fluorides for prevention of dental caries was discussed already in the 19th century in Europe <ref>Meiers, Peter: "Early Fluoride research in Europe", from the Fluoride History website, page accessed 21 May, 2006.</ref>, community water fluoridation owes its origin in part to the research of Dr. Frederick McKay, who pressed the dental community for an investigation into what was then known as "Colorado stain."<ref name="csdshistory">History of Dentistry in the Pikes Peak Region,Colorado Springs Dental Society webpage, page accessed 25 February, 2006.</ref> In 1909, of the 2,945 children seen by Dr. McKay, 87.5% had some degree of stain or mottling. All the affected children were from the Pikes Peak region. Despite having a negative impact on the physical appearance of their teeth, the children with stained or mottled teeth also had fewer cavities than other children. McKay brought the problem to the attention of Dr. G.V. Black, and Black's interest into the Colorado stain led to greater interest throughout the dental profession.
Initial hypotheses for the staining included poor nutrition, overconsumption of pork or milk, radium exposure, childhood diseases, or a calcium deficiency in the local drinking water.<ref name="csdshistory">History of Dentistry in the Pikes Peak Region,Colorado Springs Dental Society webpage, page accessed 25 February, 2006.</ref> In 1931, researchers finally concluded that the cause of the Colorado stain was a high concentration of fluoride ions (above 1 ppm) in the region's drinking water <ref>Meiers, Peter: "The Bauxite Story - A look at ALCOA", from the Fluoride History website, page accessed 12 May, 2006.</ref>. Pikes Peak's rock formations contained the mineral cryolite, one of whose constituents is fluoride. As the rain and snow fell, the resulting runoff water picked up the fluoride as it migrated to the water supply.
Dental research then moved toward determining a safe level for fluoride in water supplies. The research had two goals: (1) to warn communities with a high concentration of fluoride of the danger, initiating a reduction of the fluoride levels in order to prevent the Colorado stain, currently known as dental fluorosis, and (2) to encourage communities with a low concentration of fluoride in drinking water to increase the fluoride levels in order to help prevent tooth decay.
The classic epidemiological study to attempt to determine the optimal level of fluoride in water was led by Dr. H. Trendley Dean, a dental officer of the U.S. Public Health Service, in 1934. <ref>Dean, H.T. "Classification of mottled enamel diagnosis." Journal of the American Dental Association, 21, 1421 - 1426, 1934.</ref> <ref>Dean, H.T. "Chronic endemic dental fluorosis." Journal of the American Dental Association, 16, 1269 - 1273, 1936.</ref> His research on the fluoride - dental caries relationship, published in 1942, included 7,000 children from 21 cities in Colorado, Illinois, Indiana, and Ohio. The study concluded that the optimal level of fluoride which minimized the risk of severe fluorosis but had positive benefits for tooth decay was 1 part per million (ppm). In 1939, Dr. Gerald J. Cox <ref>Meiers, Peter: "Gerald Judy Cox".</ref> conducted laboratory tests on fluoride and suggested to add fluoride to drinking water (or other media such as milk or bottled water) in order to improve oral health.<ref>Cox, G.J., M.C. Matuschak, S.F. Dixon, M.L. Dodds, W.E. Walker. "Experimental dental caries IV. Fluorine and its relation to dental caries. Journal of Dental Research, 18, 481-490, 1939. Copy of original paper can be found here.</ref> In 1937 already, dentists Henry Klein and Carroll E. Palmer had considered the possibility of fluoridation to prevent cavities after their evaluation of data gathered by a Public Health Service team at dental examinations of American Indian children. <ref>Klein H., Palmer C.E.: "Dental caries in American Indian children", Public Health Bulletin, No. 239, Dec. 1937 </ref> In a series of papers published afterwards (1937-1941), yet disregarded by his colleagues within the U.S.P.H.S., Klein summarized his findings on tooth development in children and related problems in epidemiological investigations on caries prevalence.
In the mid 1940s, four widely-cited studies were conducted. The researchers investigated cities that had both fluoridated and unfluoridated water. The first pair was Muskegon, Michigan and Grand Rapids, Michigan, making Grand Rapids the first community in the world to modify its fluoride levels in drinking water to benefit dental health on January 25, 1945.<ref name="mntmichigan">After 60 Years of Success, Water Fluoridation Still Lacking in Many Communities. Medical News Today website, accessed 26 February, 2006.</ref> Kingston, New York was paired with Newburgh, New York. <ref>Ast, D.B., D.J. Smith, B. Wacks, K.T. Cantwell. "Newburgh-Kingston caries-fluorine study XIV. Combined clinical and roentgenographic dental findings after ten years of fluoride experience." Journal of the American Dental Association, 52, 314-25, 1956.</ref> Oak Park, Illinois was paired with Evanston, Illinois. Sarnia, Ontario was paired with Brantford, Ontario, Canada.<ref>Brown, H., M. Poplove. "The Brantford-Sarnia-Stratford Fluoridation Caries Study: Final Survey, 1963." Canadian Journal of Public Health,56, 319–24, 1965.</ref> The research found a decrease in the incidence of tooth decay in cities which had added fluoride to water supplies.
[edit] Bottled water and fluoridation
Currently, there is some concern among dental professionals that the growing use of bottled water may decrease the amount of fluoride exposure people will receive.<ref>Smith, Michael. "Bottled Water Cited as Contributing to Cavity Comeback", from the MedPage Today website, page accessed 29 April, 2006.</ref> Some bottlers such as Dannon have begun adding fluoride to their water. Most bottlers, however, do not add fluoride, and fluoride concentrations are not usually labeled on the bottle. As a result, people who have fluoridated water supplies may receive less than the amounts of fluoride that fluoride proponents recommend if they choose bottled water over tap water.
[edit] International status
[edit] United States
As of May 2000, 42 of the 50 largest U.S. cities have water fluoridation.<ref>The Benefits of Fluoride, from the Centers for Disease Control and Prevention website, accessed 19 March, 2006.</ref> 67% of Americans are living in communities with fluoridated water according to a 2002 study.<ref>Fluoridation Status: Percentage of U.S. Population on Public Water Supply Systems Receiving Fluoridated Water, from the Centers for Disease Control and Prevention website, accessed 19 March, 2006.</ref> As of 2001, 19 states have at least 75% of their population receiving fluoridated water.<ref>National Oral Health Surveillance System: Public Water Supply, from the Centers for Disease Control and Prevention.</ref> There is a CDC database for researching the water fluoridation status of neighborhood water.<ref>http://apps.nccd.cdc.gov/MWF/index.asp</ref>
In 1998, 70% of people polled in an American Dental Association survey (a pro-fluoridation group) believed community water should be fluoridated, with 18% disagreeing and the rest undecided.<ref>American Dental Association Survey Center. 1998 consumers' opinions regarding community water fluoridation. Chicago, Illinois: American Dental Association, 1998</ref>
The issue of whether or not to fluoridate waters supplies occasionally arises in local governments. For example, on November 8, 2005, citizens of Mt. Pleasant, Michigan voted 63% to 37% in favor of reinstating fluoridation in public drinking water after a 2004 ballot initiative ceased water fluoridation in the city.<ref>Crozier, Stacie. "Michigan town votes to return fluoridation" November 30, 2005.</ref> At the same time, voters in Xenia, Ohio; Springfield, Ohio; Bellingham, Washington; and Tooele City, Utah all rejected water fluoridation.<ref>http://www.noforcedfluoride.org</ref>
The cost of fluoridating water supplies in the United States has been researched.<ref name="RingelbergCost">Ringelberg, M. L., S. J. Allen, L. J. Brown. "Cost of fluoridation: 44 Florida communities.", abstract from PubMed website, page accessed 19 March, 2006.</ref> In cities with a population of over 50,000 people, fluoridation costs 31 cents per person per year. The cost rises to $2.12 per person in cities with a population below 10,000.
[edit] Canada
Approximately 40% of the Canadian population receives fluoridated water<ref>"Fluorides and Human Health", from the Health Canada website, page accessed March 25, 2006.</ref>
Implementation of fluoridation usually lies with provincial or city governments. Brantford, Ontario became the first city in Canada to fluoridate its water supplies in 1945. In 1955, Toronto approved water fluoridation, but delayed implementation of the program until 1963 due to a campaign against fluoridation by broadcaster Gordon Sinclair.<ref>"Gordon Sinclair's rant", from the Canadian Broadcasting Corporation Archives website, page accessed March 27, 2006.</ref> The city continues to fluoridate its water today.<ref>"Water supply - R. L. Clark Filtration Plant", from Toronto's website, page accessed March 27, 2006.</ref> There have been some recent decreases in the amount of fluoridation used, however, as it has decreased from 1 to 0.8 to 0.6 mg per litre. Historically, British Columbia has been the province with least percentage of its population receiving fluoridated water.<ref>"Ambient Water Quality Criteria for Fluoride", from the Environmental Protection Division of British Columbia's Ministry of Environment website, page accessed March 27, 2006.</ref> Montreal may be the last major city in Canada which does not fluoridate its water supplies.
[edit] Europe
Most of Europe does not fluoridate its water supply.The Republic of Ireland is the only EU nation to have mandatory fluoridation. In the United Kingdom 10% of the population receives fluoridated water - including two major cities: Birmingham and Newcastle upon Tyne.<ref>Mullen, Joe. "History of Water Fluoridation", British Dental Journal, 2005, page accessed April 29, 2006.</ref> <p> After a consultation on children's oral health, Scotland retained permissive legislation allowing health authorites to request fluoridation of the water supply.<p> France does not fluoridate its water supply. As "[f]luoride chemicals are not included in the list [of 'chemicals for drinking water treatment']. This is due to ethical as well as medical considerations.", Directeur de la Protection de l'Environment, August 25, 2000). However, the use of fluoridated salt is widespread <ref>P Tramini. Schweiz Monatsschr Zahnmed 2005, 115; 12-14.</ref><p> Germany has rejected water fluoridation. As the German Federal Minster of Health "[g]enerally, in Germany fluoridation of drinking water is forbidden. The relevant German law allows exceptions to the fluoridation ban on application (as was the case in the Kassel-Wahlershausen experiment in the 1950´s). The argumentation, in 1999, of the Federal Ministry of Health against a general permission of fluoridation of drinking water is the problematic nature of compuls[ory] medication." (Gerda Hankel-Khan, Embassy of Federal Republic of Germany, September 16, 1999). However, experience shows that opinions change with the official in charge. In common with France and Switzerland, the use of fluoridated salt is widespread in Germany <ref>Andreas G Shulte. Schweiz Monatsschr Zahnmed 2005, 115; 15-18</ref>.<p> In Switzerland since 1962 two fluoridation programmes had operated in tandem: water fluoridation in the City of Basel, and salt fluoridation in the rest of Switzerland (around 83% of domestic salt sold had fluoride added). However it became increasingly difficult to keep the two programmes separate. As a result some of the population of Basel were assumed to use both fluoridated salt and fluoridated water. In order to correct that situation, in April 2003 the State Parliament agreed to cease water fluoridation and officially expand salt fluoridation to Basel <ref>J. MEYER and P. Wiehl in Schweiz Monatsschr. Zahnmed 2003; 113: 702 (in French) and 728-729 (in German)</ref>.
[edit] Other
The government of South Africa supports the fluoridation of water supplies.<ref>"Water Fluoridation - The Facts", from South Africa's Department of Health website, page accessed April 29, 2006.</ref>
In Brazil, about 45% of the cities have a fluoridated water supply. Government studies reported a decrease in cavities on the affected population between 40% and 80%.<ref>Fluoretação da Água em Sistema Público de Abastecimento, page accessed April 29, 2006.</ref>
In Chile 70.5% of the population receive fluoridated water (10.1 million adjusted, 604,000 naturally occurring)<ref>Information from the Oral Health Department of the Chilean Ministry of Health. December 2004.</ref>.
Australia has fluoridation in all but one state, Queensland, in which water fluoridation is under local government control. The City of Geelong, west of Melbourne, does not fluoridate its water supplies. This is despite the fact that all of Melbourne's water is fluoridated. Many regional centres in Queensland do fluoridate their water supply, however Brisbane, the state capital, currently does not add fluoride to its drinking water. The first town to fluoridate the water supply in Australia was Beaconsfield, Tasmania in 1953.<ref> (1987) “Tasmania”, Editors: Graham Aplin, S.G. Foster and Michael McKernan: Australians:Events and Places. Sydney, NSW, Australia: Fairfax, Syme & Weldon Associates, page 366. ISBN 0-521-34073-X. </ref>
[edit] Malfunctions in water fluoridation equipment
Water fluoridation equipment has, on occasion, malfunctioned in the United States. Perhaps the worst incident in the United States occurred in Hooper Bay, Alaska in 1992. When fluoridation equipment failed, a large amount of fluoride was released into the drinking water supply and "296 people were poisoned; 1 person died,"[1] marking the "first reported death due to fluoride toxicity caused by drinking water from a community water system."[2]
[edit] Controversy
- See main article Water fluoridation controversy
Water fluoridation by public authorities has occasionally provoked controversy. Advocates of water fluoridation say that fluoridation is similar to fortifying salt with iodine, milk with vitamin D and orange juice with vitamin C and say it is an effective way to prevent tooth decay. Those opposed to public fluoridation of drinking water say that water fluoridation can have negative health effects such as dental fluorosis, bone cancer and osteoporosis which outweighs the purported benefits of water fluoridation. Some opponents claim that releasing fluoride compounds into municipal water takes away individual choice as to the substances a person ingests and amounts to mass medication.
[edit] Popular culture
Water fluoridation has received some attention in popular culture. Stanley Kubrick's 1964 film Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb satirized an urban legend declaring water fluoridation to be a communist conspiracy.
[edit] See also
[edit] References
[edit] External links
- [3] York Review Executive Summary, Water Fluoridation
- CDC database for the fluoridation status of neighborhood water
- Letter on fluoridation from EPA (PDF) supporting fluoridation hosted by ADA
- History of Water Fluoridation
- 1970s discussion on fluoridation
- World Health Organization report on fluorine and fluorides (1984)
- "Environmental Health Criteria for Fluorides," World Health Organization (2002)
- Fluoride Deception = Poison In Your Water - A 30 minute video explaining some of the controversy in depth.de:Fluoridierung
