Water fluoridation is the controlled addition of fluoride to a public water supply to reduce tooth decay, and is handled differently by countries across the world.
Water fluoridation is considered very common in the United States, Canada, Ireland, Chile and Australia where over 50% of the population drinks fluoridated water.
Most European countries including Italy, France, Finland, Germany, Sweden, Netherlands, Scotland, Austria, Poland, Hungary and Switzerland do not fluoridate water, but use fluoridated salt, milk, and toothpastes to reduce cavities.
Fluoridated water contains fluoride at a level that is proven effective for preventing cavities; this can occur naturally or by adding fluoride. Fluoridated water creates low levels of fluoride in saliva, which reduces the rate at which tooth enamel demineralizes, and increases the rate at which it remineralizes in the early stages of cavities. Typically, a fluoridated compound is added to drinking water, a process that in the U.S. costs an average of about $ per person-year. Defluoridation is needed when the naturally occurring fluoride level exceeds recommended limits. In 2011, the World Health Organization suggested a level of fluoride from 0.5 to 1.5 mg/L (milligrams per liter), depending on climate, local environment, and other sources of fluoride.Guidelines for Drinking-water Quality, 4th Edition WHO, 2011. . Page 168, 175, 372 and see also pp 370-73. See also J. Fawell, et al Fluoride in Drinking-water. WHO, 2006. Page 32. Quote: "Concentrations in drinking-water of about 1 mg l–1 are associated with a lower incidence of dental caries, particularly in children, whereas excess intake of fluoride can result in dental fluorosis. In severe cases this can result in erosion of enamel. The margin between the beneficial effects of fluoride and the occurrence of dental fluorosis is small and public health programmes seek to retain a suitable balance between the two" Bottled water typically has unknown fluoride levels.
Health effects Dental cavities remain a major public health concern in most industrialized countries, affecting 60–90% of schoolchildren and the vast majority of adults. Water fluoridation may slightly reduce cavities in children, while efficacy in adults is less clear. Recent studies suggest that water fluoridation, particularly in industrialized countries, may be unnecessary because topical fluorides (such as in toothpaste) are widely used and cavity rates have become low. For this reason, some scientists consider fluoridation to be unethical due to the lack of informed consent. However, a recent study funded by NHS found no significant difference between individuals who receive fluoridated water and those who don't in terms of missing teeth and reducing social inequities.
Although fluoridation can cause dental fluorosis, which can alter the appearance of developing teeth or enamel fluorosis, the differences are mild and usually not considered to be of aesthetic or public-health concern. Summary: There is no clear evidence of other adverse effects from water fluoridation, as revealed by the York review from 2000. Report website: Authors' summary: Authors' commentary: A 2007 Australian systematic review used the same inclusion criteria as York's, plus one additional study. This did not affect the York conclusions. Fluoride's effects depend on the total daily intake of fluoride from all sources. Drinking water is typically the largest source; other methods of fluoride therapy include fluoridation of toothpaste, salt, and milk. The views on the most effective method for community prevention of tooth decay are mixed. The Australian government states that water fluoridation is the most effective means of achieving fluoride exposure that is community-wide. The World Health Organization states water fluoridation, when feasible and culturally acceptable, has substantial advantages, especially for subgroups at high risk, while the European Commission finds no advantage to water fluoridation compared with topical use.
Currently about 372 million people (around 5.7% of the world population) receive artificially fluoridated water in about 24 countries, including Australia, Brazil, Canada, Chile, Republic of Ireland, Malaysia, the U.S., and Vietnam. 57.4 million people receive naturally occurring fluoridated water at or above optimal levels in countries such as Sweden, China, Sri Lanka, Finland, Zimbabwe and Gabon. Community water fluoridation is rare in Continental Europe, with 97–98% choosing not to fluoridate drinking water. Fluoridated salt and milk is promoted in some European countries instead. Water fluoridation has been replaced by other modes in many countries where water supplies are too decentralized for it to be a practical choice, or existing natural fluoride levels were already ample, including Germany, Finland, Japan, Netherlands, Sweden, Switzerland (Switzerland has 1 mg fluoride per 1 liter, USA only between 0.3 mg and 0.7 mg) water Denmark and at a time Israel. Cessation of water fluoridation has been demonstrated in scientific studies such as a recent one in Calgary, Alberta, to result in increased rates of dental decay. While fluoridation can result in mild dental fluorosis, this effect is barely detectable and causes no concerns with the appearance or health of teeth. Countries practicing artificial water fluoridation vary in their recommended fluoride levels according to what health authorities in each have determined to be most effective for its citizens. The US recently reset the recommended optimal level of fluoride in drinking water, lowering it slightly, because of observed increased fluorosis levels, likely due to additional fluoride sources like toothpaste and mouthwash which were not present when this level was originally set.
Africa Libya Before 2003, 400,000 Libyans were receiving artificially fluoridated water.
Nigeria Only a fraction of Nigerians receive water from waterworks, so water fluoridation affects very few people. A 2009 study found that about 21% of water sources naturally contain fluoride to the recommended range of 0.3–0.6 ppm. About 62% have fluoride below this range.
South Africa South Africa's Health Department recommends adding fluoridation chemicals to drinking water in some areas. It also advises removal of fluoride from drinking water (defluoridation) where the fluoride content is too high.ml "Water Fluoridation – The Facts", from South Africa's Department of Health website. Retrieved 29 April 2006.
Legislation around mandatory fluoridation was introduced in 2002, but has been delayed since then pending further research after opposition from water companies, municipalities and the public.
Zambia Approximately 947,000 (7% of the population) receives water with naturally occurring fluoride in it.
Zimbabwe Roughly 2,600,000 (21% of the population) receives water with naturally occurring fluoride in it.
Asia
China Many areas in China have fluoride at levels far higher than recommended due to natural occurrence or industrial contamination, which has resulted in a large amount of skeletal fluorosis. Water fluoridation levels are set at a national standard of 1 mg/L, with higher levels for rural areas at 1.2 mg/L. Water fluoridation began in 1965 in the urban area of Guangzhou. It was interrupted during 1976–1978 due to the shortage of sodium silico-fluoride. It was resumed only in the Fangcun district of the city, but was halted in 1983 after opponents claimed that fluoride levels were already sufficiently high in local foods and tea. Later analysis in 1988 found that the incidence of dental caries among 4-year-old children had increased by 62%. The fluoridation reduced the number of cavities, but increased dental fluorosis; the fluoride levels could have been set too high, and low-quality equipment led to inconsistent, and often excessive, fluoride concentrations.
Hong Kong All Hong Kong residents receive natural occurring fluoride in water, at about half the traditionally recommended fluoride level. The Water Supplies Department fluoridates rainwater from 17 local reservoirs, in 21 treatment plants. Recent tests showed drinking water to have an average fluoride level of 0.48 mg/L, and a maximum of 0.69 mg/L.
India Water fluoridation is not practiced in India.Ingram, Colin. (2006). The Drinking Water Book. pp. 15-16 Due to naturally occurring fluoride, both skeletal and dental fluorosis have been endemic in India in at least 20 states, including Uttarakhand, Jharkhand and Chhattisgarh. The maximum permissible limit of fluoride in drinking water in India is 1.2 mg/L, and the government has been obligated to install fluoride removal plants of various technologies to reduce fluoride levels from industrial waste and mineral deposits. Now reverse osmosis plants are widely used. Household and public system reverse osmosis plants are common in the market. Alleppey in Kerala is most affected with over-fluoridated water. Government-installed reverse osmosis plants supply free filtered water. Rotary International Club, Saratoga USA, helped to install 3 RO Plants in rural Alleppey.
, there are 14,132 habitations in 19 States still containing fluoride above the permissible levels in drinking water. Rajasthan has the highest number of habitations (7,670) with high amount of fluoride in drinking water. Telangana has 1174, Karnataka has 1122 and Madhya Pradesh has 1055 habitation. Assam, Andhra Pradesh, Bihar, Chhattisgarh, Maharashtra, Odisha, West Bengal and Uttar Pradesh also has such habitations.
The government of India launched the National Programme for Prevention and Control of Fluorosis in 2008–2009. In 2013–2014, the programme was brought under the National Rural Health Mission, which has so far covered 111 districts. The programme includes surveillance of fluorosis in the community, training and manpower support, establishment of diagnostic facilities, treatment and health education. The Indian Council of Medical Research has formed a task force on fluorosis to address issues related to prevention and control.
Israel Fluoride was required in water supplies nationwide by legislation passed in 2002, but the requirement was repealed in 2014, and artificial fluoridation was disparaged by national health officials, effectively ending the practice in Israel for a short while.Press Releases (17 August 2014) End of Mandatory Fluoridation in Israel , Ministry of Health (Israel). Retrieved 29 September 2014. After the election of 2015 the fluoridation program was to be re-debated the new deputy Health Minister Yaakov Litzman.
Mekorot, Israel's national water company states, "In the South of the country, it is unnecessary to add fluoride because it is found naturally in the water." Water fluoridation was introduced in Israel's large cities in 1981, and a national effort to fluoridate all the country's water was approved in 1988.
In 2002, the Union of Local Authorities (ULA) and others petitioned Israel's High Court to stop the Health Ministry from forcing cities to implement water fluoridation. The court soon issued a restraining order, but after half a year ULA withdrew its petition upon the request of the court.
By 2011, about 65% of the municipalities and local authorities in Israel had agreed to allow fluoridation, and there was active opposition to the spread of fluoridation to the towns where it has not yet been instituted. In 2011, the Health and Welfare Committee of the Knesset criticized the Health Ministry for continuation of water fluoridation.