When was fluorine first introduced in tap water?
Water fluoridation
Health and dental organizations worldwide have endorsed its safety and effectiveness. Its use began in 1945, following studies of children in a region where higher levels of fluoride occur naturally in the water. Further research showed that moderate fluoridation prevents tooth decay.
Water fluoridation controversy
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.
Greater Winnipeg Water District aqueduct
Equipment to fluoridate the water supply was installed at the aqueduct intake and operations commenced on 28 December 1956.
History of water filters
Limited drinking water standards were first implemented in the US in 1914, but it would not be until the 1940s that federal drinking water standards were widely applied. In 1972, the Clean Water Act passed through Congress and became law, requiring industrial plants to proactively improve their waste procedures in order to limit the effect of contaminants on freshwater sources. In 1974, the Safe Drinking Water Act was adopted by all 50 U.S. states for the regulation of public water systems within their jurisdictions.
Water fluoridation controversy
Public water fluoridation was first practiced in 1945, in the US. As of 2012, 25 countries have supplemental water fluoridation to varying degrees, and 11 of them have more than 50% of their population drinking fluoridated water. A further 28 countries have water that is naturally fluoridated, though in many of them there are areas where fluoride is above the optimum level. As of 2012 about 435 million people worldwide received water fluoridated at the recommended level, of whom 57 million (13%) received naturally fluoridated water and 377 million (87%) received artificially fluoridated water. In 2014, three-quarters of the US population on the public water supply received fluoridated water, which represented two-thirds of the total US population.
Water purification
Permanent water chlorination began in 1905, when a faulty slow sand filter and a contaminated water supply led to a serious typhoid fever epidemic in Lincoln, England. Dr. Alexander Cruickshank Houston used chlorination of the water to stem the epidemic. His installation fed a concentrated solution of chloride of lime to the water being treated. The chlorination of the water supply helped stop the epidemic and as a precaution, the chlorination was continued until 1911 when a new water supply was instituted.
The first continuous use of chlorine in the United States for disinfection took place in 1908 at Boonton Reservoir (on the Rockaway River), which served as the supply for Jersey City, New Jersey. Chlorination was achieved by controlled additions of dilute solutions of chloride of lime (calcium hypochlorite) at doses of 0.2 to 0.35 ppm. The treatment process was conceived by Dr. John L. Leal and the chlorination plant was designed by George Warren Fuller. Over the next few years, chlorine disinfection using chloride of lime were rapidly installed in drinking water systems around the world.
History of fluorine
English chemist George Gore also tried electrolyzing dry HF and may have made small quantities of fluorine gas in 1860. He reported an explosion after running his cell (hydrogen and fluorine recombine dramatically), but he recognized that an oxygen leak could have also caused the reaction.
Cardinia Reservoir
Construction of the dam was completed in 1973, following which it took another four years to fill, including substantial water transfers from Silvan Reservoir. As part of the Victorian Government's policy that fluoride should be added to all public water supplies, construction began on local fluoridation plants. In 1981, following continued demand for potable water on the Mornington Peninsula finally exceeded the district's ability to meet its own water supply needs. Despite upgrading of existing facilities, water from the MMBW reservoir at Cardinia was first used to supplement local water supplies. Export of "Australia Pure", a bottled water from Cardinia Reservoir, commenced in 1993 to several European countries and the United States of America.
Water fluoridation controversy
The World Health Organization, looking at global public health, identifies fluoride as one of a few chemicals for which the contribution from drinking-water to overall intake is an important factor in preventing disease. This is because there is clear evidence that optimal concentrations of fluoride provide protection against cavities, both in children and in adults.
History of fluorine
Moissan also constructed special apparatus—5m long platinum tubes with fluorite windows—to determine the slight yellow color of fluorine gas. (The gas appears transparent in small tubes or when allowed to escape. The color observation was not repeated until the 1980s, when his result was confirmed.)
Water supply
The first documented use of sand filters to purify the water supply dates to 1804, when the owner of a bleachery in Paisley, Scotland, John Gibb, installed an experimental filter, selling his unwanted surplus to the public. The first treated public water supply in the world was installed by engineer James Simpson for the Chelsea Waterworks Company in London in 1829. The practice of water treatment soon became mainstream, and the virtues of the system were made starkly apparent after the investigations of the physician John Snow during the 1854 Broad Street cholera outbreak demonstrated the role of the water supply in spreading the cholera epidemic.
History of water supply and sanitation
Permanent water chlorination began in 1905, when a faulty slow sand filter and a contaminated water supply led to a serious typhoid fever epidemic in Lincoln, England. Dr. Alexander Cruickshank Houston used chlorination of the water to stem the epidemic. His installation fed a concentrated solution of chloride of lime to the water being treated. The chlorination of the water supply helped stop the epidemic and as a precaution, the chlorination was continued until 1911 when a new water supply was instituted.
The first continuous use of chlorine in the United States for disinfection took place in 1908 at Boonton Reservoir (on the Rockaway River), which served as the supply for Jersey City, New Jersey. Chlorination was achieved by controlled additions of dilute solutions of chloride of lime (calcium hypochlorite) at doses of 0.2 to 0.35 ppm. The treatment process was conceived by Dr. John L. Leal and the chlorination plant was designed by George Warren Fuller. Over the next few years, chlorine disinfection using chloride of lime were rapidly installed in drinking water systems around the world.
Water chlorination
Chlorine gas was first used on a continuing basis to disinfect the water supply at the Belmont filter plant, Philadelphia, Pennsylvania by using a machine invented by Charles Frederick Wallace who dubbed it the Chlorinator. It was manufactured by the Wallace & Tiernan company beginning in 1913. By 1941, disinfection of U.S. drinking water by chlorine gas had largely replaced the use of chloride of lime.
Dune water
In 1851 a dune water company, Amsterdamsche Duinwater-Maatschappij, was founded in Amsterdam. This was the very first tap water company in the Netherlands. Since 1953 water was pumped from the dunes and transported to Amsterdam through a pipeline. Pumping up the fresh water from the dunes caused the ground water level to drop so in 1957 it was decided that river water had to infiltrated to replenish the supply. After the sand filtered the river water, it was pumped up and purified for human consumption. This Dutch process is unique in the world.
Since 1975 the water is purified before infiltration. By using ozonisation and charcoal the Dutch purify their water without using chlorine. Tap water in the Netherlands is considered to be amongst the highest quality municipal waters in the world.
History of fluorine
In 1810, French physicist André-Marie Ampère suggested that hydrofluoric acid was a compound of hydrogen with an unknown element, analogous to chlorine. Fluorite was then shown to be mostly composed of calcium fluoride.
Fluoride
Fluoride-containing compounds, such as sodium fluoride or sodium monofluorophosphate are used in topical and systemic fluoride therapy for preventing tooth decay. They are used for water fluoridation and in many products associated with oral hygiene. Originally, sodium fluoride was used to fluoridate water; hexafluorosilicic acid (HSiF) and its salt sodium hexafluorosilicate (NaSiF) are more commonly used additives, especially in the United States. The fluoridation of water is known to prevent tooth decay and is considered by the U.S. Centers for Disease Control and Prevention as "one of 10 great public health achievements of the 20th century". In some countries where large, centralized water systems are uncommon, fluoride is delivered to the populace by fluoridating table salt. For the method of action for cavity prevention, see Fluoride therapy. Fluoridation of water has its critics (see Water fluoridation controversy). Fluoridated toothpaste is in common use, but is only effective at concentrations above 1,000 ppm, as is common in North America and Europe.
Portland, Oregon
As of 2012, Portland was the largest city in the United States that did not add fluoride to its public water supply, and fluoridation has historically been a subject of controversy in the city. Portland voters have four times voted against fluoridation, in 1956, 1962, 1980 (repealing a 1978 vote in favor), and 2013. In 2012 the city council, responding to advocacy from public health organizations and others, voted unanimously to begin fluoridation by 2014. Fluoridation opponents forced a public vote on the issue, and on May 21, 2013, city voters again rejected fluoridation.
Mae Pu Kha
San Kamphaeng District, where Mae Pu Ka is located, is an area where the groundwater contains high levels of fluoride up to 4.8 – 15 mg/l. Certain studies found that residents’ urinary fluoride levels were elevated and that the highest risk of fluoride ingestion comes from cooking rice with fluoride-containing water because of a lack of knowledge on fluoride sources and fluoride chemistry.
Olafur Eliasson
In 1998, Olafur discovered that uranin, a readily available nontoxic powder used to trace leaks in plumbing systems, could dye entire rivers a sickly fluorescent green. Olafur conducted a test run in the Spree River during the 1998 Berlin Biennale, scattering a handful of powder from a bridge near Museum Island. He began introducing the environmentally safe dye to rivers in Moss, Norway (1998), Bremen (1998), Los Angeles (1999), Stockholm (2000) and Tokyo (2001) — always without advance warning.
Bottled water
Bottled water in New Zealand is regulated by Food Standards Australia New Zealand and must comply with the Food Act 1981. From July 2009 fluoride was allowed to be present in bottled water as an additive or as a natural occurring mineral.
Water fluoridation in the United States
The U.S. Centers for Disease Control has identified community water fluoridation as one of ten great public health achievements of the 20th century. The CDC recommends water fluoridation at a level of 0.7–1.2 mg/L, depending on climate. The CDC also advises parents to monitor use of fluoride toothpaste, and use of water with fluoride concentrations above 2 mg/L, in children up to age 8. There is a CDC database for researching the water fluoridation status of neighborhood water.
Baixo Guandu
Baixo Guandu was the first Brazilian city to receive water treated with fluoride in 1953 in order to reduce the incidence of caries, especially among children.
Dental public health
The development of artificial water fluoridation began in 1945 in the Grand rapid Michigan followed by Newburgh, New York and Evanston, Illinois. In 1955 three towns Watford, Kilmarnock and Anglesey trialled the water fluoridation implementation scheme. In 1960 the Republic of Ireland implemented all public water supplies with artificial fluoridated water and four years later extending this into the main cities of Dublin and Cork.
Fluoridation by country
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. After the election of 2015 the fluoridation program is to be re-debated the new deputy Health Minister Yaakov Litzman.
Tooth enamel
Many groups of people have spoken out against fluoridated drinking water, for reasons such as the neurotoxicity of fluoride or the damage fluoride can do as fluorosis. Fluorosis is a condition resulting from the overexposure to fluoride, especially between the ages of 6 months and 5 years, and appears as mottled enamel. Consequently, the teeth look unsightly, although the incidence of dental decay in those teeth is very small. Where fluoride is found naturally in high concentrations, filters are often used to decrease the amount of fluoride in water. For this reason, codes have been developed by dental professionals to limit the amount of fluoride a person should take. These codes are supported by the American Dental Association and the American Academy of Pediatric Dentistry;
Water fluoridation in Australia
Several areas of Queensland, such as Julia Creek, Quilpie, Thargomindah and Adavale are known to have naturally occurring fluoride present in their drinking water, a characteristic that has been studied since the late 1920s.
Oxygen difluoride
Oxygen difluoride was first reported in 1929; it was obtained by the electrolysis of molten potassium fluoride and hydrofluoric acid containing small quantities of water. The modern preparation entails the reaction of fluorine with a dilute aqueous solution of sodium hydroxide, with sodium fluoride as a side-product:
Fluoridation by country
In 1956, Singapore was the first Asian country to institute a water fluoridation program that covered 100% of the population. Water is fluoridated to a typical value of 0.4-0.6 mg per litre.
Fluoridation by country
The first community water fluoridation programme was in Kyoto prefecture in 1952, lasting 13 years. The second was established by US military authorities in Okinawa prefecture in 1957, lasting 15 years. The last experience was in Mie Prefecture in 1967, lasting 4 years.
Irene Vorrink
She also took the leading role in attempting to establish a legal basis for the fluoridation of drinking water. Though fluoridation to prevent tooth decay had been occurring in many areas across the Netherlands for years, the Supreme Court ruled in 1973 that it should be specifically provided for in the Water Supply law. Her bill to do so did not find support in the House of Representatives outside her own party, and was dropped.
Dental fluorosis
In 1931, 3 different groups of scientists around the world published their discoveries that this condition was caused by fluoride in drinking water during childhood. The condition then started to become termed "dental fluorosis". Through epidemiological studies in the USA, Henry Trendley Dean helped to identify a causal link between high concentrations of fluoride in the drinking water and mottled enamel. He also produced a classification system for dental fluorosis that is still used in modern times, Dean's Index. As research continued, the protective effect of fluoride against dental decay was demonstrated.
Fluoridation by country
In 2013, a Hamilton City Council committee voted to remove fluoride from late June 2013. A referendum was held during the council elections in October 2013 with approximately 70% of voters voting for fluoride to be added back into the water supply, and in March 2014, the council voted 9 to 1 to re-introduce fluoride into the supply. In a 2007 referendum about half of voters in the Central Otago, South Otago and the Southland Region did not want fluoridation and voters in the Waitaki District were against water fluoridation for all Wards. Ashburton and Greymouth also voted against fluoridation.
Water purification
The Metropolis Water Act introduced the regulation of the water supply companies in London, including minimum standards of water quality for the first time. The Act "made provision for securing the supply to the Metropolis of pure and wholesome water", and required that all water be "effectually filtered" from 31 December 1855. This was followed up with legislation for the mandatory inspection of water quality, including comprehensive chemical analyses, in 1858. This legislation set a worldwide precedent for similar state public health interventions across Europe. The Metropolitan Commission of Sewers was formed at the same time, water filtration was adopted throughout the country, and new water intakes on the Thames were established above Teddington Lock. Automatic pressure filters, where the water is forced under pressure through the filtration system, were innovated in 1899 in England.
Water chlorination
Permanent water chlorination began in 1905, when a faulty slow sand filter and a contaminated water supply caused a serious typhoid fever epidemic in Lincoln, England. Dr. Alexander Cruickshank Houston used chlorination of the water to stop the epidemic. His installation fed a concentrated solution of so-called "chloride of lime" to the water being treated. This was not simply modern calcium chloride, but contained chlorine gas dissolved in lime-water (dilute calcium hydroxide) to form calcium hypochlorite (chlorinated lime). The chlorination of the water supply helped stop the epidemic and as a precaution, the chlorination was continued until 1911 when a new water supply was instituted.
The first continuous use of chlorine in the United States for disinfection took place in 1908 at Boonton Reservoir (on the Rockaway River), which served as the supply for Jersey City, New Jersey. Chlorination was achieved by controlled additions of dilute solutions of chloride of lime (calcium hypochlorite) at doses of 0.2 to 0.35 ppm. The treatment process was conceived by Dr. John L. Leal, and the chlorination plant was designed by George Warren Fuller. Over the next few years, chlorine disinfection using chloride of lime (calcium hypochlorite) were rapidly installed in drinking water systems around the world.
Water fluoridation
The critical period of exposure is between ages one and four years, with the risk ending around age eight. Fluorosis can be prevented by monitoring all sources of fluoride, with fluoridated water directly or indirectly responsible for an estimated 40% of risk and other sources, notably toothpaste, responsible for the remaining 60%. Compared to water naturally fluoridated at 0.4 mg/L, fluoridation to 1 mg/L is estimated to cause additional fluorosis in one of every 6 people (95% CI 4–21 people), and to cause additional fluorosis of aesthetic concern in one of every 22 people (95% CI 13.6–∞ people). Here, "aesthetic concern" is a term used in a standardized scale based on what adolescents would find unacceptable, as measured by a 1996 study of British 14-year-olds. In many industrialized countries the prevalence of fluorosis is increasing even in unfluoridated communities, mostly because of fluoride from swallowed toothpaste. A 2009 systematic review indicated that fluorosis is associated with consumption of infant formula or of water added to reconstitute the formula, that the evidence was distorted by publication bias, and that the evidence that the formula's fluoride caused the fluorosis was weak. In the U.S. the decline in tooth decay was accompanied by increased fluorosis in both fluoridated and unfluoridated communities; accordingly, fluoride has been reduced in various ways worldwide in infant formulas, children's toothpaste, water, and fluoride-supplement schedules.
Fluoridation by country
In 1957, the Department of Health established a Fluorine Consultative Council which recommended fluoridation at 1.0 ppm of public water supplies, then accessed by approximately 50% of the population. This was felt to be a much cheaper way of improving the quality of children's teeth than employing more dentists. This led to the Health (Fluoridation of Water Supplies) Act 1960, which mandated compulsory fluoridation by local authorities. The statutory instruments made in 1962–65 under the 1960 Act were separate for each local authority, setting the level of fluoride in drinking water to 0.8–1.0 ppm. The current regulations date from 2007, and set the level to 0.6–0.8 ppm, with a target value of 0.7 ppm.
Defluoridation
Fluorosis was not identified as a problem until relatively recently. Few attempts to defluoridate water came before the 20th century. In the 1930s several nations began to investigate fluoride's negative effects and how best to remove it. An aluminum and sand filter that removes fluorine from water was devised by Dr. S. P. Kramer in 1933; in 1945 M. Kenneth received a French patent for a water defluoridation technique; and in 1952 a functioning activated alumina community defluoridation plant was commissioned in Bartlett, Texas, USA.
Water fluoridation
Communities have discontinued water fluoridation in some countries, including Finland, Germany, Japan, the Netherlands, and Switzerland. On 26 August 2014, Israel stopped mandating fluoridation, stating "Only some 1% of the water is used for drinking, while 99% of the water is intended for other uses (industry, agriculture, flushing toilets etc.). There is also scientific evidence that fluoride in large amounts can lead to damage to health. When fluoride is supplied via drinking water, there is no control regarding the amount of fluoride actually consumed, which could lead to excessive consumption. Supply of fluoridated water forces those who do not so wish to also consume water with added fluoride. This approach is therefore not accepted in most countries in the world." This change was often motivated by political opposition to water fluoridation, but sometimes the need for water fluoridation was met by alternative strategies. The use of fluoride in its various forms is the foundation of tooth decay prevention throughout Europe; several countries have introduced fluoridated salt, with varying success: in Switzerland and Germany, fluoridated salt represents 65% to 70% of the domestic market, while in France the market share reached 60% in 1993 but dwindled to 14% in 2009; Spain, in 1986 the second West European country to introduce fluoridation of table salt, reported a market share in 2006 of only 10%. In three other West European countries, Greece, Austria and the Netherlands, the legal framework for production and marketing of fluoridated edible salt exists. At least six Central European countries (Hungary, the Czech and Slovak Republics, Croatia, Slovenia, Romania) have shown some interest in salt fluoridation; however, significant usage of approximately 35% was only achieved in the Czech Republic. The Slovak Republic had the equipment to treat salt by 2005; in the other four countries attempts to introduce fluoridated salt were not successful.
Fluorine
Among the elements, fluorine ranks 24th in universal abundance and 13th in terrestrial abundance. Fluorite, the primary mineral source of fluorine which gave the element its name, was first described in 1529; as it was added to metal ores to lower their melting points for smelting, the Latin verb "" meaning "flow" gave the mineral its name. Proposed as an element in 1810, fluorine proved difficult and dangerous to separate from its compounds, and several early experimenters died or sustained injuries from their attempts. Only in 1886 did French chemist Henri Moissan isolate elemental fluorine using low-temperature electrolysis, a process still employed for modern production. Industrial production of fluorine gas for uranium enrichment, its largest application, began during the Manhattan Project in World War II.
Water fluoridation
In the first half of the 19th century, investigators established that fluoride occurs with varying concentrations in teeth, bone, and drinking water. In the second half they speculated that fluoride would protect against tooth decay, proposed supplementing the diet with fluoride, and observed mottled enamel (now called severe dental fluorosis) without knowing the cause. In 1874, the German public health officer Carl Wilhelm Eugen Erhardt recommended potassium fluoride supplements to preserve teeth. In 1892 the British physician James Crichton-Browne noted in an address that fluoride's absence from diets had resulted in teeth that were "peculiarly liable to decay", and who proposed "the reintroduction into our diet ... of fluorine in some suitable natural form ... to fortify the teeth of the next generation".
Fluorine deficiency
Disputes over the essentiality of fluorine date back to the 19th century, when fluorine was observed in teeth and bones. In 1973 a trial found reduced reproduction in mice fed fluorine-deficient diets, but a subsequent investigation determined that this was due to reduced iron absorption.
Philadelphia Water Department
The Philadelphia Water Department has been providing water to citizens since 1801, when, in the aftermath of a series of devastating yellow fever epidemics that killed thousands of people, the City decided a source of water was needed to cleanse the streets, fight fires, and perform household chores. While a number of private water companies had been established in other cities by that time, Philadelphia, with its city-owned and financed system, was one of the first in the U.S. to take on water supply as a municipal responsibility. Water was piped throughout the city, with paying customers served by direct lines to businesses and houses, and free water provided through public hydrants to anyone with a bucket to carry it in.
Water fluoridation controversy
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.
Water fluoridation in the United States
In 1937, 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 Native American children. 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.
1953 in Australia
The following lists events that happened during 1953 in Australia.The first town to fluoridate the water supply in Australia was Beaconsfield, Tasmania.
History of water filters
The first documented use of sand filters to purify the water supply dates to 1804, when the owner of a bleachery in Paisley, Scotland, John Gibb, installed an experimental filter, selling his unwanted surplus to the public. This method was refined in the following two decades by engineers working for private water companies, and it culminated in the first treated public water supply in the world, installed by engineer James Simpson for the Chelsea Waterworks Company in London in 1829. This installation provided filtered water for every resident of the area, and the network design was widely copied throughout the United Kingdom in the ensuing decades.
Water fluoridation controversy
Opposition to fluoridation has existed since its initiation in the 1940s. During the 1950s and 1960s, conspiracy theorists claimed that fluoridation was a communist plot to undermine American public health. In recent years water fluoridation has become a prevalent health and political issue in many countries, resulting in some countries and communities discontinuing its use while others have expanded it. The controversy is propelled by a significant public opposition supported by a minority of professionals, which include researchers, dental and medical professionals, alternative medical practitioners, health food enthusiasts, a few religious groups (mostly Christian Scientists in the U.S.), and occasionally consumer groups and environmentalists. Organized political opposition has come from libertarians, the John Birch Society, and from groups like the Green parties in the UK and New Zealand.
1961 Edmonton municipal election
Shall fluorides, for the prevention of tooth decay, be added to the City water supply sufficient to bring the fluorine content of City water up to a level of one part fluorine to one million parts of water?
Fluoridation by country
The use of water fluoridation first began in New Zealand in Hastings in 1954. A Commission of Inquiry was held in 1957 and then its use rapidly expanded in the mid 1960s. New Zealand now has fluoridated water supplied to about half of the total population. Of the six main centers, only Christchurch and Tauranga do not have a fluoridated water supply. Wellington's water supply is mostly fluoridated, but the suburbs of Petone and Korokoro receive a non-fluoridated supply. In Auckland, the suburbs Onehunga and Huia Village don't fluoridate water.
Water fluoridation in the United States
A study of varying amounts of fluoride in water was led by Dr. H. Trendley Dean, a dental officer of the U.S. Public Health Service. In 1936 and 1937, Dr. Dean and other dentists compared statistics from Amarillo, which had 2.8 – 3.9 mg/L fluoride content, and low fluoride Wichita Falls. The data is alleged to show fewer cavities in Amarillo children, but the studies were never published. Dr. Dean's 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 amount of fluoride which minimized the risk of severe fluorosis but had positive benefits for tooth decay was 1 mg per day, per adult. Although fluoride is more abundant in the environment today, this was estimated to correlate with the concentration of 1 mg/L.
Fluoridation by country
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.
Acridine orange
In 1942, Hilbrich and Strugger were first described using acridine orange to detect the fluorochromatic staining of microorganisms. Since then the use of acridine orange has been performed frequently in the examination of soil and water for microbial content. Direct counts of aquatic bacteria by using epifluorescent methods were evaluated by Jones and Simon in 1975. They also determined that the best estimation of the bacterial population in lake, river, and seawater samples can be achieved using acridine orange.
Water fluoridation in the United States
In Skagit County in the state of Washington, the county commissioners in 2007 voted 2 to 1 to order the local public utility district to begin fluoridating the public water supply by Jan. 2009. $1.2 million was to be provided by the privately funded Washington Dental Service Foundation to begin building the equipment needed to add fluoride to the Judy Reservoir, which supplies the majority of Skagit Valley's water customers. The source and type of fluoride to be added to the drinking water of more than 70,000 citizens had not been disclosed. However, in February 2009, Skagit County commissioners rescinded the 2007 order, citing costs and possible lawsuits.
Bottled water
In some areas, tap water may contain added fluoride, which helps prevent tooth decay and cavities. Some bottled water manufacturers in the United States add fluoride to their product, or provide a fluoridated bottled water product. The Food and Drug Administration of the United States does not require bottled water manufacturers to list the fluoride content on the label. However, unlike tap water where the amount of fluoride added by municipalities to drinking water is not federally regulated, the FDA has set specific limits for how much fluoride may be found in bottled water. Water fluoridation remains controversial in countries that require it (the United States, United Kingdom, Ireland, Canada, Australia, and a handful of other countries).Several studies have examined the content of fluoride and other chemicals in bottled water as well as the accuracy of these values as printed on the labels showing some significant difference between labeled and measured value.
William Guy Carr
In the 1950s, both organisations fought communism and were involved in a campaign against water fluoridation (brochure, 1956; articles about the topic were also published in "News Behind the News" in 1958). The historian Daniel Pipes studied that particular case and mentioned that "in the 1950s, the National Federation of Christian Laymen portrayed fluorine as the 'devil's poison and considered its addition to drinking water to prevent tooth decay to be "one of the most dastardly plots ever attempted against the human race."
History of fluorine
The word "fluorine" derives from the Latin stem of the main source mineral, fluorite, which was first mentioned in 1529 by Georgius Agricola, the "father of mineralogy". He described fluorite as a flux—an additive that helps melt ores and slags during smelting. Fluorite stones were called "schone flusse" in the German of the time. Agricola, writing in Latin but describing 16th century industry, invented several hundred new Latin terms. For the "schone flusse" stones, he used the Latin noun "fluores", "fluxes", because they made metal ores flow when in a fire. After Agricola, the name for the mineral evolved to fluorspar (still commonly used) and then to fluorite.
2000 Flushes
In October 1993, toilet fixture manufacturers reported rapid degradation of flush valve flappers; some new, water-saving toilets (introduced to meet a 1994 US federal water conservation deadline) were leaking within months of installation. The growing popularity of in-tank drop-in cleaning tablets quickly drew suspicion as many contain chlorine bleach; if a toilet is flushed infrequently, the amount of chlorine in the tank may build to problematic levels. The Metropolitan Water District of Southern California (MWD) began tests of flapper materials in 1994-1997. By 1998, flappers had been redesigned to withstand continuous immersion in 2000 Flushes or Clorox bowl cleaners, then the most popular products. A rival in-tank cleaner introduced by Vanish in 2000 caused problems until new durability and marking requirements for flappers were added to the ASME A112.19.5 standard in 2005.
Hans Rudolf Mühlemann
During his years in the United States, Mühlemann had learned that caries incidence could be significantly reduced through fluoridation of the communal water supply. The assumption at that time was that fluoride by way of the blood vascular system would be incorporated into tooth substance during tooth development, and positively affect caries resistance. Mühlemann was able to demonstrate that fluoride was also effective when applied topically after tooth eruption; this led him to the development of fluoride-containing dentifrice and mouthwash, and also to the fluoridation of table salt. He created a Caries Research Station led by Klaus G. König, who was called to a professorship in Nijmegen, the Netherlands, in 1968.
Water fluoridation
Fluoridation does not affect the appearance, taste, or smell of drinking water. It is normally accomplished by adding one of three compounds to the water: sodium fluoride, fluorosilicic acid, or sodium fluorosilicate.
Water fluoridation controversy
Fluoridation began during a time of great optimism and faith in science and experts (the 1950s and 1960s), but even then, the public frequently objected. Opponents drew on distrust of experts and unease about medicine and science. Controversies include disputes over fluoridation's benefits and the strength of the evidence basis for these benefits, the difficulty of identifying harms, legal issues over whether water fluoride is a medicine, and the ethics of mass intervention.
Water fluoridation in the United States
Fluoridation became an official policy of the U.S. Public Health Service by 1951, and by 1960 water fluoridation had become widely used in the U.S., reaching about 50 million people. By 2006, 69.2% of the U.S. population on public water systems were receiving fluoridated water, amounting to 61.5% of the total U.S. population. Near the end of 2012, 67.1% of the U.S. population were getting water from community water systems (CWS) supplying water that had fluoride at or above recommended levels. Those included the 3.5% of the population that were on CWS with naturally occurring fluoride at or above recommended levels. 74.6% of those on CWS were receiving water with fluoride at or above recommended levels.
Water fluoridation in Australia
Fluoride has been added to public water supplies in Darwin (since 1972), Katherine, and Gove. Similarly to South Australia, there is no legal requirement to add fluoride to the Northern Territory's water supplies, but a position paper published in November 2010 strongly encourages water providers to add fluoride where possible. Supplies south of Elliott have naturally occurring fluoride at levels sufficient to provide an oral health benefit. Approximately 9% of the population of Northern Territory have naturally fluoridated water. As of 2012, 70% of the population in the Northern Territory has access to fluoridated water, and there are plans to extend access to more residents by 2015.
Fluorine
Population studies from the mid-20th century onwards show topical fluoride reduces dental caries. This was first attributed to the conversion of tooth enamel hydroxyapatite into the more durable fluorapatite, but studies on pre-fluoridated teeth refuted this hypothesis, and current theories involve fluoride aiding enamel growth in small caries. After studies of children in areas where fluoride was naturally present in drinking water, controlled public water supply fluoridation to fight tooth decay began in the 1940s and is now applied to water supplying 6 percent of the global population, including two-thirds of Americans. Reviews of the scholarly literature in 2000 and 2007 associated water fluoridation with a significant reduction of tooth decay in children. Despite such endorsements and evidence of no adverse effects other than mostly benign dental fluorosis, opposition still exists on ethical and safety grounds. The benefits of fluoridation have lessened, possibly due to other fluoride sources, but are still measurable in low-income groups. Sodium monofluorophosphate and sometimes sodium or tin(II) fluoride are often found in fluoride toothpastes, first introduced in the U.S. in 1955 and now ubiquitous in developed countries, alongside fluoridated mouthwashes, gels, foams, and varnishes.
Water fluoridation
In the 1930s and early 1940s, H. Trendley Dean and colleagues at the newly created U.S. National Institutes of Health published several epidemiological studies suggesting that a fluoride concentration of about 1 mg/L was associated with substantially fewer cavities in temperate climates, and that it increased fluorosis but only to a level that was of no medical or aesthetic concern. Other studies found no other significant adverse effects even in areas with fluoride levels as high as 8 mg/L. To test the hypothesis that adding fluoride would prevent cavities, Dean and his colleagues conducted a controlled experiment by fluoridating the water in Grand Rapids, Michigan, starting 25 January 1945. The results, published in 1950, showed significant reduction of cavities. Significant reductions in tooth decay were also reported by important early studies outside the U.S., including the Brantford–Sarnia–Stratford study in Canada (1945–1962), the Tiel–Culemborg study in the Netherlands (1953–1969), the Hastings study in New Zealand (1954–1970), and the Department of Health study in the U.K. (1955–1960). By present-day standards these and other pioneering studies were crude, but the large reductions in cavities convinced public health professionals of the benefits of fluoridation.
Water fluoridation in Australia
Approximately 95% of the population has access to fluoridated water (September 2011). Fluoridation commenced in New South Wales with Yass in 1956, with Sydney fluoridating in 1968. The use of fluoride is regulated by the Fluoridation of Public Water Supplies Act 1957, and the Fluoridation of Public Water Supplies Regulation 2007.
Fluoridation by country
Water was fluoridated in large parts of the Netherlands from 1960 to 1973, when the High Council of The Netherlands declared fluoridation of drinking water unauthorized. Dutch authorities had no legal basis for adding chemicals to drinking water if they would not contribute to a sound water supply. Drinking water has not been fluoridated in any part of the Netherlands since 1973.
History of fluorine
French chemist Henri Moissan, formerly one of Frémy's students, continued the search. After trying many different approaches, he built on Frémy and Gore's earlier attempts by combining potassium bifluoride and hydrogen fluoride. The resultant solution conducted electricity. Moissan also constructed especially corrosion-resistant equipment: containers crafted from a mixture of platinum and iridium (more chemically resistant than pure platinum) with fluorite stoppers.
Water fluoridation
The foundation of water fluoridation in the U.S. was the research of the dentist Frederick McKay (1874–1959). McKay spent thirty years investigating the cause of what was then known as the Colorado brown stain, which produced mottled but also cavity-free teeth; with the help of G.V. Black and other researchers, he established that the cause was fluoride. The first report of a statistical association between the stain and lack of tooth decay was made by UK dentist Norman Ainsworth in 1925. In 1931, an Alcoa chemist, H.V. Churchill, concerned about a possible link between aluminum and staining, analyzed water from several areas where the staining was common and found that fluoride was the common factor.
Water fluoridation in the United States
In 2012, New Hampshire began requiring public water systems that fluoridate to post the following notice in their consumer confidence reports: "Your public water supply is fluoridated. According to the Centers for Disease Control and Prevention, if your child under the age of 6 months is exclusively consuming infant formula reconstituted with fluoridated water, there may be an increased chance of dental fluorosis. Consult your child's health care provider for more information." The law was passed with overwhelming majorities in the legislature and took effect August 4.
Water fluoridation
The history of water fluoridation can be divided into three periods. The first () was research into the cause of a form of mottled tooth enamel called the Colorado brown stain. The second (c. 1933–1945) focused on the relationship between fluoride concentrations, fluorosis, and tooth decay, and established that moderate levels of fluoride prevent cavities. The third period, from 1945 on, focused on adding fluoride to community water supplies.
Water chlorination
In a paper published in 1894, it was formally proposed to add chlorine to water to render it "germ-free". Two other authorities endorsed this proposal and published it in many other papers in 1895. Early attempts at implementing water chlorination at a water treatment plant were made in 1893 in Hamburg, Germany. In 1897 the town of Maidstone, England was the first to have its entire water supply treated with chlorine.
Water fluoridation
Much of the early work on establishing the connection between fluoride and dental health was performed by scientists in the U.S. during the early 20th century, and the U.S. was the first country to implement public water fluoridation on a wide scale. It has been introduced to varying degrees in many countries and territories outside the U.S., including Argentina, Australia, Brazil, Canada, Chile, Colombia, Hong Kong, Ireland, Israel, Korea, Malaysia, New Zealand, the Philippines, Serbia, Singapore, Spain, the UK, and Vietnam. In 2004, an estimated 13.7 million people in western Europe and 194 million in the U.S. received artificially fluoridated water. In 2010, about 66% of the U.S. population was receiving fluoridated water.
Water supply
Permanent water chlorination began in 1905, when a faulty slow sand filter and a contaminated water supply led to a serious typhoid fever epidemic in Lincoln, England. Dr. Alexander Cruickshank Houston used chlorination of the water to stem the epidemic. His installation fed a concentrated solution of chloride of lime to the water being treated. The first continuous use of chlorine in the United States for disinfection took place in 1908 at Boonton Reservoir (on the Rockaway River), which served as the supply for Jersey City, New Jersey.
Desalination appeared during the late 20th century, and is still limited to a few areas.
Water fluoridation in Australia
On 29 November 2012 the Queensland Parliament, with a Liberal National Party government, reversed the previous Labor government's mandate requiring certain public potable water supplies to add fluoride to the water. As a consequence of these changes local councils in Queensland have the choice to add fluoride to drinking water supplies, similar to the conditions in place under the previous legislation. In January 2013 the Cairns council decided to discontinue water fluoridation.
History of chemistry
Davy also experimented with gases by inhaling them. This experimental procedure nearly proved fatal on several occasions, but led to the discovery of the unusual effects of nitrous oxide, which came to be known as laughing gas. Chlorine was discovered in 1774 by Swedish chemist Carl Wilhelm Scheele, who called it ""dephlogisticated marine acid"" (see phlogiston theory) and mistakenly thought it contained oxygen. Scheele observed several properties of chlorine gas, such as its bleaching effect on litmus, its deadly effect on insects, its yellow-green colour, and the similarity of its smell to that of aqua regia. However, Scheele was unable to publish his findings at the time. In 1810, chlorine was given its current name by Humphry Davy (derived from the Greek word for green), who insisted that chlorine was in fact an element. He also showed that oxygen could not be obtained from the substance known as oxymuriatic acid (HCl solution). This discovery overturned Lavoisier's definition of acids as compounds of oxygen. Davy was a popular lecturer and able experimenter.
Water fluoridation controversy
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.
Water fluoridation
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.
Fluoridation by country
The first town to fluoridate the water supply in Australia was Beaconsfield, Tasmania in 1953. Queensland became the last state to formally require the addition of fluoride to public drinking water supplies in December 2008.
Water fluoridation in the United States
In 1939, Dr. Gerald J. Cox conducted laboratory tests using rats that were fed aluminum and fluoride. Dr. Cox suggested adding fluoride to drinking water (or other media such as milk or bottled water) in order to improve oral health.
Fluoridation by country
Fluoridation is banned in China. Naturally high fluoride levels in water are a serious problem in China. As of 2003, there is no water fluoridation in China. 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, due to objections, and was halted in 1983. 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.
Fluorine
Historically, most cases of fluoride poisoning have been caused by accidental ingestion of insecticides containing inorganic fluorides. Most current calls to poison control centers for possible fluoride poisoning come from the ingestion of fluoride-containing toothpaste. Malfunctioning water fluoridation equipment is another cause: one incident in Alaska affected almost 300 people and killed one person. Dangers from toothpaste are aggravated for small children, and the Centers for Disease Control and Prevention recommends supervising children below six brushing their teeth so that they do not swallow toothpaste. One regional study examined a year of pre-teen fluoride poisoning reports totaling 87 cases, including one death from ingesting insecticide. Most had no symptoms, but about 30% had stomach pains. A larger study across the U.S. had similar findings: 80% of cases involved children under six, and there were few serious cases.
Flumequine
The first quinolone used was nalidixic acid (was marketed in many countries as Negram) followed by the fluoroquinolone flumequine. The first-generation fluoroquinolone agents, such as flumequine, had poor distribution into the body tissues and limited activity. As such they were used mainly for treatment of urinary tract infections. Flumequine (benzo quinolizine) was first patented in 1973, (German Patent) by Rikker Labs. Flumequine is a known antimicrobial compound described and claimed in U.S. Pat. No. 3,896,131 (Example 3), July 22, 1975. Flumequine is the first quinolone compound with a fluorine atom at the C6-position of the related quinolone basic molecular structure. Even though this was the first fluoroquinolone, it is often overlooked when classifying the drugs within this class by generations and excluded from such a list.
History of water supply and sanitation
The first documented use of sand filters to purify the water supply dates to 1804, when the owner of a bleachery in Paisley, Scotland, John Gibb, installed an experimental filter, selling his unwanted surplus to the public. This method was refined in the following two decades by engineers working for private water companies, and it culminated in the first treated public water supply in the world, installed by engineer James Simpson for the Chelsea Waterworks Company in London in 1829. This installation provided filtered water for every resident of the area, and the network design was widely copied throughout the United Kingdom in the ensuing decades.
History of municipal treatment of drinking water
As understanding of the bacteriological nature of disease became clearer in the late 19th century the need to filter and treat water became apparent. In Lowell, MA after a typhoid outbreak in 1890 William Thompson Sedgwick applied bacteriological methods to the investigation and was able to establish a link between contaminated water and the disease. The United States by this time had begun to introduce filtration into its municipal water supplies as a means of removing sediment form water in the 1870s through 90s. The United States also introduced the rapid sand filter which were a derivation of filters used in the paper making industry. The rapid filters and the slow sand filters engaged in competition as to which technology was superior. By the beginning of the 20th century, an increased knowledge in bacteriology led to improvements in the slow sand filters as well as the design of rapid filters. It soon became apparent that slow sand filters could remove typhoid germs.
John L. Leal
John Laing Leal (May 5, 1858 – March 13, 1914) was a physician and water treatment expert who, in 1908, was responsible for conceiving and implementing the first disinfection of a U.S. drinking water supply using chlorine. He was one of the principal expert witnesses at two trials which examined the quality of the water supply in Jersey City, New Jersey, and which evaluated the safety and utility of chlorine for production of "pure and wholesome" drinking water. The second trial verdict approved the use of chlorine to disinfect drinking water which led to an explosion of its use in water supplies across the U.S.
Drinking water supply and sanitation in the United States
In 1854, the British physician John Snow found that cholera was spread through contaminated water. As a result of his findings, several cities began to treat all water with sand filters and chlorine before distributing it to the public. Before efforts to clean drinking water were implemented at the turn of the 20th century, mortality among 1- to 5-year-olds in the United States in some major river cities was nearly one in five. Clean water is estimated to have reduced about three-fourths of infant mortality, and two-thirds of child mortality. By 1900, sand filtration was widely used. In 1908, the first continuous application of chlorination to drinking U.S. water was in Jersey City, New Jersey (and not without controversy). Cities also began to construct sewers. As a result of water treatment and sanitation, the incidence of cholera and typhoid rapidly decreased. Slow sand filtration was initially the technology of choice for water treatment, later being gradually displaced by rapid sand filtration.
Fluoridation by country
Australia now provides fluoridated water for 70% or more of the population in all states and territories. Many of Australia's drinking water supplies began fluoridation in the 1960s and 1970s. By 1984 almost 66% of the Australian population had access to fluoridated drinking water, represented by 850 towns and cities. Some areas within Australia have natural fluoride levels in the groundwater, which was estimated in 1991 to provide drinking water to approximately 0.9% of the population.
Fluoridation by country
On 26 August 2014, Israel officially stopped adding fluoride to its water supplies. According to a Ministry of Health press release statement, the reasons it ended water fluoridation were: "Only some 1% of the water is used for drinking, while 99% of the water is intended for other uses (industry, agriculture, flushing toilets etc.). There is also scientific evidence that fluoride in large amounts can lead to damage to health. When fluoride is supplied via drinking water, there is no control regarding the amount of fluoride actually consumed, which could lead to excessive consumption. Supply of fluoridated water forces those who do not so wish to also consume water with added fluoride." Many in the medical and dental communities in Israel criticized the decision as a mistake.
Selectfluor
1-Chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) or Selectfluor, a trademark of Air Products and Chemicals, is a reagent in chemistry that is used as a fluorine donor. This compound is a derivative of the heterocycle DABCO . This colourless salt was first described in 1992 and has since been commercialized for use in organofluorine chemistry for electrophilic fluorination.
Drinking water quality in the United States
Most people associate fluoride with the practice of intentionally adding fluoride to public drinking-water supplies for the prevention of tooth decay. However, fluoride can also enter public water systems from natural sources, including runoff from weathering of fluoride-containing rocks and soils and leaching from soil into groundwater. Fluoride pollution from various industrial emissions can also contaminate water supplies. In a few areas of the United States, fluoride concentrations in water are much higher than normal, mostly from natural sources. In 1986, EPA established a maximum allowable concentration for fluoride in drinking water of 4 milligrams per liter (mg/L). After reviewing research on various health effects from exposure to fluoride, the Committee on Fluoride in Drinking Water of the National Research Council concluded in 2006 that EPA's drinking water standard for fluoride does not protect against adverse health effects. Just over 200,000 Americans live in communities where fluoride levels in drinking water are 4 mg/L or higher. Children in those communities are at risk of developing severe tooth enamel fluorosis, a condition that can cause tooth enamel loss and pitting. It can also increase the risk of bone fractures. The report concluded unanimously that the present maximum contaminant level goal of 4 mg/L for fluoride should be lowered.
Water fluoridation controversy
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. In some other countries, sodium fluoride is added to table salt.
History of water supply and sanitation
The technique of purification of drinking water by use of compressed liquefied chlorine gas was developed by a British officer in the Indian Medical Service, Vincent B. Nesfield, in 1903. According to his own account, "It occurred to me that chlorine gas might be found satisfactory ... if suitable means could be found for using it... The next important question was how to render the gas portable. This might be accomplished in two ways: By liquefying it, and storing it in lead-lined iron vessels, having a jet with a very fine capillary canal, and fitted with a tap or a screw cap. The tap is turned on, and the cylinder placed in the amount of water required. The chlorine bubbles out, and in ten to fifteen minutes the water is absolutely safe. This method would be of use on a large scale, as for service water carts."
Water purification
In a paper published in 1894, Moritz Traube formally proposed the addition of chloride of lime (calcium hypochlorite) to water to render it "germ-free." Two other investigators confirmed Traube's findings and published their papers in 1895. Early attempts at implementing water chlorination at a water treatment plant were made in 1893 in Hamburg, Germany and in 1897 the city of Maidstone England was the first to have its entire water supply treated with chlorine.
History of fluorine
After 74 years of effort by many chemists, on 26 June 1886, Moissan isolated elemental fluorine. Moissan's report to the French Academy of making fluorine showed appreciation for the feat: "One can indeed make various hypotheses on the nature of the liberated gas; the simplest would be that "we are in the presence of fluorine"."
Fluoridation by country
In 1952, Norrköping in Sweden became one of the first cities in Europe to fluoridate its water supply. It was declared illegal by the Supreme Administrative Court of Sweden in 1961, re-legalized in 1962 and finally prohibited by the parliament in 1971, after considerable debate. The parliament majority said that there were other and better ways of reducing tooth decay than water fluoridation. Four cities received permission to fluoridate tap water when it was legal. An official commission was formed, which published its final report in 1981. They recommended other ways of reducing tooth decay (improving food and oral hygiene habits) instead of fluoridating tap water. They also found that many people found fluoridation to infringe upon personal liberty/freedom of choice by forcing them to be medicated, and that the long-term effects of fluoridation were insufficiently acknowledged. They also lacked a proper study on the effects of fluoridation on formula-fed infants. In the year 2004 the allowed amount of fluoride in the water was decreased to 1,5 mg/l.
Milan, Tennessee
In 1950, the Milan National Guard became one of the first two in the nation to be federalized into active duty. In 1951, led by Dr. Robert P. Denney, Milan became the first city in Tennessee, second in the Southeast, to fluoridate its drinking water.
Water fluoridation in the United States
In 1952, a Federal Regulation was adopted that stated in part, "The Federal Security Agency will regard water supplies containing fluorine, within the limitations recommended
by the Public Health Service, as not actionable under the Federal Food, Drug, and Cosmetic Act."
Fluoridation by country
Water fluoridation was first adopted in Brazil in the city of Baixo Guandu, ES, in 1953. A 1974 federal law required new or enlarged water treatment plants to have fluoridation, and its availability was greatly expanded in the 1980s, with optimum fluoridation levels set at 0.8 mg/L. Today, the expansion of fluoridation in Brazil is a governmental priority; Between 2005 and 2008, fluoridation became available to 7.6 million people in 503 municipalities. As of 2008, 3,351 municipalities (60.6%) had adopted fluoridation, up from 2,466 in 2000.
Activated alumina
Activated alumina is also widely used to remove fluoride from drinking water. In the US, there are widespread programs to fluoridate drinking water. However, in certain regions, such as the Rajasthan region of India, there is enough fluoride in the water to cause fluorosis. A study from the Harvard school of Public Health found exposure to fluoride as a child correlated with lower IQ.
Tooth enamel
Furthermore, whereas topical fluoride, found in toothpaste and mouthwashes, does not cause fluorosis, its effects are now considered more important than those of systemic fluoride, such as when drinking fluorinated water. However, systemic fluoride works topically as well with fluoride levels in saliva increase also when drinking fluoridated water. Lately, dental professionals are looking for other ways to present fluoride (such as in varnish) or other mineralizing products such as Amorphous calcium phosphate to the community in the form of topical procedures, either done by professionals or self-administered. Mineralization of the incipient lesion instead of restoration later is a prime goal of most dental professionals.
History of fluorine
Andreas Sigismund Marggraf made the first definite preparation of hydrofluoric acid in 1764 when he heated fluorite with sulfuric acid in glass, which was greatly corroded by the product. In 1771, Swedish chemist Carl Wilhelm Scheele repeated this reaction. Scheele recognized the product of the reaction as an acid, which he called "fluss-spats-syran" (fluor-spar-acid); in English, it was known as "fluoric acid".