1.4 Uses in Water Treatment Fluoride is added to the water supply to reduce the incidence of dental caries. Hydrofluosilicic acid, sodium fluoride and sodium silicofluoride are the fluoride compounds that are commonly used for this purpose.
What chemicals are used to fluoridate drinking water?
The fluoride chemicals used to fluoridate drinking water are: fluorosilicic acid, sodium fluorosilicate, and sodium fluoride. Unlike the fluoride compounds found in toothpaste or supplements, fluoridation chemicals are not pharmaceutical grade quality.
What are the uses of fluoride?
1.4 Uses in Water Treatment Fluoride is added to the water supply to reduce the incidence of dental caries. Hydrofluosilicic acid, sodium fluoride and sodium silicofluoride are the fluoride compounds that are commonly used for this purpose.
What is sodium fluoride additive?
Sodium fluoride: a dry salt additive, typically used in small water systems, dissolved into a solution before being added to water. Most fluoride additives used in the United States are produced from phosphorite rock.
What are the sources of fluoride in water?
Sources of Fluoride Additives. Since the early 1950s, FSA has been the main additive used for water fluoridation in the United States. The favorable cost and high purity of FSA make it a popular additive. Sodium fluorosilicate and sodium fluoride come from processing FSA, or from processing hydrogen fluoride.
What type of fluoride is used in water?
Types of Fluoride Additives Fluorosilicic acid: a water-based solution used by most water systems in the United States. Fluorosilicic acid is also referred to as hydrofluorosilicate, FSA, or HFS. Sodium fluorosilicate: a dry salt additive, dissolved into a solution before being added to water.
How is fluoride treated in water?
A reverse osmosis filtration system is a simple solution for removing fluoride from drinking water. A Reverse Osmosis (RO) system can remove 85-92%* of fluoride in your water. Essentially, reverse osmosis technology uses household water pressure to push tap water through the filtration process.
What is fluoride made of?
Fluoride is created when salts from the element fluorine combine with minerals in soil or rocks. Due to its simple origins, fluoride is found naturally in soil, water and many foods. It also occurs naturally in the human body in bones and teeth.
What is fluoride used for?
Fluoride is used to prevent tooth decay. It is taken up by teeth and helps to strengthen teeth, resist acid, and block the cavity-forming action of bacteria. Fluoride usually is prescribed for children and adults whose homes have water that is not fluoridated (already has fluoride added).
How is fluoride treated in groundwater?
The different adsorbents used for fluoride removal include activated alumina, carbon, bone charcoal and synthetic ion exchange resins. Membrane filtration process Reverse osmosis and electrodialysis are two membrane filtration processes which can be used for removal of fluoride.
Why is fluoride used in drinking water?
Drinking fluoridated water keeps teeth strong and reduces cavities (also called tooth decay) by about 25% in children and adults. By preventing cavities, community water fluoridation has been shown to save money both for families and for the US health care system.
What is the best source of fluoride?
Natural Sources of FluorideSeafood. Seafood like crab legs and shrimp are not only a delicious and fancy delicacy, but also among the best natural sources of fluoride.Wine, Juice, Grapes and Raisins. ... Fruit. ... Potatoes. ... Coffee and Black Tea. ... Talking to Your Dentist About Fluoride.
What is sodium fluoride chemical compound?
Sodium fluorideSodium fluoride / IUPAC IDSodium fluoride (NaF) is an inorganic compound with the formula NaF. It is used in trace amounts in the fluoridation of drinking water, in toothpaste, in metallurgy, and as a flux, and is also used in pesticides and rat poison. It is a colorless or white solid that is readily soluble in water.
What are fluoride supplements?
Fluoride supplements (tablets, drops, lozenges or chewing gums) for preventing tooth decay in children. Tooth decay (dental caries) can cause pain and lead to loss of teeth. In most developed countries, the prevalence of dental caries has decreased in the past 30 years in child populations.
Where does the fluoride in our water come from?
The mineral fluoride occurs naturally on earth and is released from rocks into the soil, water, and air. All water contains some fluoride. Usually, the fluoride level in water is not enough to prevent tooth decay; however, some groundwater and natural springs can have naturally high levels of fluoride.
What was the first compound used for fluoridation?
Sodium fluoride (NaF) – The first compound ever used for fluoridation. Found in about 28% of the public water supply.
How to reduce fluoride in tap water?
The best way to reduce fluoride levels present in a home’s tap water is to have a reverse osmosis drinking water system installed . Reverse osmosis (R.O.) removes fluoride ions and filters out many other things in water as well. That includes, lead, arsenic, and certain microorganisms. Find out how R.O. systems work here on our blog. An R.O. system provides a more permanent and less expensive drinking water option over purchasing bottled water. Many bottled water brands also add fluoride within the recommended range. See a list here.
How Does Fluoride End Up in Water?
It is done for the specific purpose of preventing and reducing tooth decay (dental caries) among the population. Fluoridation does not impact the taste, smell, or appearance of water.
Why is fluoride in toothpaste dangerous?
There are recommended levels for fluoride content because consuming too much of the mineral can be toxic. That’s why fluoridated toothpaste contains a warning about ingesting the product. If a child were to consume an entire tube of toothpaste, that could be a concern.
What is the fluoride level in the Great Lakes?
A large portion of the western U.S., and certain areas of the Great Lakes region are known to have groundwater fluoride levels above 1.5 mg/L, exceeding government recommendations.
What is the maximum fluoride level in water?
In recent years, the Department of Health and Human Services (HHS), the Environmental Protection Agency (EPA), and the Food and Drug Administration (FDA) lowered recommendations for fluoride levels to a maximum of 0.7 mg/L for both tap and bottled water. Contact your local water authority for more information on what’s being added to the public water supply where you live.
What is the problem with water fluoridation?
This is a change in the appearance of tooth enamel due to excessive consumption of fluoride. It usually looks like small white marks on the teeth. Severe fluorosis may cause brown spots or pitting on the teeth. Dental fluorosis is an aesthetic issue, and typically does not impact tooth function or cause discomfort.
How is fluoride different from water treatment chemicals?
There are more than 40 chemical additives that can be used to treat drinking water. Fluoride is added solely for the alleged purpose of helping prevent tooth decay. Other treatment chemicals such as chlorine and chloramine are added to disinfect, reduce turbidity or prevent the corrosion of pipes. Unlike disinfectants, fluoride is far more difficult to remove from water, requiring a specialized media (and lots of it) in order to be effective.
What is fluoride?
Fluorine ( 9 F) is the 13th most abundant element in the earth's crust. Proposed as an element in 1810, fluorine exists as a highly toxic gas in its standard state, and is extremely reactive. It is not found in the atmosphere, as it reacts easily to water vapor. Instead, it is most significantly found in the minerals fluorite, fluorapatite and cryolite. 1
What is water fluoridation?
Water fluoridation is the controlled addition of a fluorine compound to a public water supply.4 The three most common compounds added to drinking water are:
What are the concerns and potential health risks associated with water fluoridation?
Competing viewpoints argue whether it is a public health achievement, or an unnecessary, even dangerous, contaminant.
How can I find out if my public water system adds fluoride to the water?
Contact your water utility supplier to find out your water is fluoridated. You can locate the name and contact information of your water utility supplier on your water bill. The EPA mandates that all community water systems provide customers with an annual report on water quality, including the fluoride content.
How can I reduce fluoride in my water?
As mentioned briefly above, once added to water, fluoride is very difficult to remove. There are only a few reliable methods to do so: reverse osmosis, deionization, and filtration with the correct media. The two primary media types are activated alumina and bone char. The preferred media, and de-facto worldwide standard for fluoride filtration is activated alumina.
What about carbon-based filter elements?
Carbon-based filter elements look similar to (though do not necessarily perform like) Black Berkey® Purification Elements. What is critical to understand is that while most carbon-based filters will initially reduce fluoride, they typically experience a drastic decline in their effectiveness usually within the first 50 gallons or less. In order to ensure long term fluoride reduction, a separate fluoride reduction filter is required, as this provides the proper amount of media (activated alumina) and proper contact time in order for effective long term fluoride reduction to take place.
What is fluoride in water?
Water fluoridation is the controlled adjustment of fluoride to a public water supply solely to reduce tooth decay. Fluoridated water contains fluoride at a level that is effective for preventing cavities; this can occur naturally or by adding fluoride.
Where is fluoridated water used?
Naturally fluoridated water is used by approximately 4% of the world's population, in countries including Argentina, France, Gabon, Libya, Mexico, Senegal, Sri Lanka, Tanzania, the U.S., and Zimbabwe. In some locations, notably parts of Africa, China, and India, natural fluoridation exceeds recommended levels.
How can fluorosis be prevented?
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.
Why is water fluoridation controversial?
The water fluoridation controversy arises from political, moral, ethical, economic, and safety concerns regarding the water fluoridation of public water supplies. For deprived groups in both maturing and matured countries, international and national agencies and dental associations across the world support the safety and effectiveness of water fluoridation. Authorities' views on the most effective fluoride therapy for community prevention of tooth decay are mixed; some state water fluoridation is most effective, while others see no special advantage and prefer topical application strategies.
How many countries have fluoridated water?
As of 2012, 25 countries have artificial water fluoridation to varying degrees, 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 the fluoride is above the optimal level. As of 2012, about 435 million people worldwide received water ...
How much fluoride is in bottled water?
Environmental Protection Agency (EPA) lowered the recommended level of fluoride to 0.7 mg/L. In 2015, the U.S. Food and Drug Administration (FDA), based on the recommendation of the U.S. Public Health Service (PHS) for fluoridation of community water systems, recommended that bottled water manufacturers limit fluoride in bottled water to no more than 0.7 milligrams per liter (mg/L) (milligrams per liter, equivalent to parts per million ).
Why is water fluoride important?
The goal of water fluoridation is to prevent a chronic disease whose burdens particularly fall on children and the poor. Another of the goals was to bridge inequalities in dental health and dental care. Some studies suggest that fluoridation reduces oral health inequalities between the rich and poor, but the evidence is limited. There is anecdotal but not scientific evidence that fluoride allows more time for dental treatment by slowing the progression of tooth decay, and that it simplifies treatment by causing most cavities to occur in pits and fissures of teeth. Other reviews have found not enough evidence to determine if water fluoridation reduces oral-health social disparities.
What chemicals are used to fluorate water?
The fluoride chemicals used to fluoridate drinking water are: fluorosilicic acid, sodium fluorosilicate, and sodium fluoride. Unlike the fluoride compounds found in toothpaste or supplements, fluoridation chemicals are not pharmaceutical grade quality. They are, instead, unpurified industrial by-products that are collected in the air pollution control systems of certain industries.
Where do fluoride chemicals come from?
Until recently, all fluoridation chemicals were obtained from the wet scrubbing systems of the phosphate fertilizer industry in central Florida. In recent years, however, an increasing number of water departments have begun purchasing their fluoride chemicals from China.
How much arsenic is in fluoridation water?
In 2000, the National Sanitation Foundation (NSF) released the results of its tests that showed fluoridation chemicals can add as much as 1.66 ppb arsenic to the finished water. NSF found that about 40% of the fluoridation chemicals it tested were contaminated with detectable levels of arsenic. Fluoridating water with these contaminated samples, the NSF stated, would add 0.43 ppb arsenic to the finished water.
What gases are released from phosphate fertilizer?
Phosphate Fertilizer Industry (Florida, US) In the process of converting phosphate rock into soluble fertilizer, two very toxic fluoride gases are released: hydrogen fluoride and silicon tetrafluoride. In the past, the phosphate industry used to let these two gases vent freely into the atmosphere.
Is there still arsenic in fluoride?
According to these new tests, there is still detectable arsenic contamination in 43% of fluoridation chemicals. However, the highest arsenic level detected would contribute 0.6 ppb to finished water, and thus not exceed the 1 ppb “product failure” threshold.
Does fluoride add arsenic to water?
According to a review in the American Water Works Association’s publication Opflow, the amount of arsenic that fluoridation adds to finished water “ is hardly a minimal amount .”. The arsenic problem is unique to fluoridation chemicals as no other water treatment chemical has a problem with arsenic contamination.
Does fluoride increase lead?
The current evidence, therefore, does suggest that fluoridating water supplies can increase the lead exposure of some children, particularly those living in old homes and in communities where both hydrofluorosilicic acid and chloramines are added to the water.
What is fluoride rinse?
Fluoride mouth rinse is a concentrated solution intended for daily or weekly use. The most common fluoride compound used in mouth rinse is sodium fluoride. Over-the-counter solutions of 0.05% sodium fluoride (230 ppm fluoride) for daily rinsing are available for use by persons older than 6 years of age.
How old do you have to be to take fluoride?
All fluoride supplements must be prescribed by a dentist or physician. For children aged less than 6 years, the dentist, physician, or other health care provider should weigh the risk for tooth decay without fluoride supplements, the decay prevention offered by supplements, and the potential for dental fluorosis.
How to prevent dental fluorosis in children?
For children aged 6 years and younger, some simple recommendations are advised to reduce the risk of dental fluorosis. Supervise brushing to discourage swallowing toothpaste. Place only a small pea-size amount of fluoride toothpaste on your child’s toothbrush.
What is the active ingredient in Form#N#Tablets?
Form#N#Tablets, lozenges, or liquids (including fluoride-vitamin preparations) are available. Most supplements contain sodium fluoride as the active ingredient. Tablets and lozenges are manufactured with 1.0, 0.5, or 0.25 mg fluoride.
Can you use fluoride varnish on children?
Recommendations. No published evidence indicates that professionally applied fluoride varnish is a risk factor for dental fluorosis, even among children younger than 6 years of age.
Can you take fluoride for tooth decay?
Fluoride supplements can be prescribed for children at high risk for tooth decay and whose primary drinking water has a low fluoride concentration. To maximize the topical effect of fluoride, tablets and lozenges are intended to be chewed or sucked for 1–2 minutes before being swallowed. Availability.
Can you buy fluoride rinse over the counter?
Availability. Mouth rinses intended for home use can be purchased over-the-counter. Higher strength mouth rinses for those at high risk of tooth decay must be prescribed by a dentist or physician. Recommendations.
Why do we need fluoridated water?
The reason for wanting a fluoridated water supply in the first place is the first thing we should consider, and it’s based on the chemical structure of your teeth. The enamel that coats your teeth is made up primarily of the compound hydroxyapatite. This ionic compound consists of calcium ions, phosphate ions and hydroxide ions, and is also a major component of your bones. Enamel is well known for being pretty strong, but it can be slowly broken down and lose ions from its structure under acidic conditions. This is known as demineralisation. Our body has a built-in countermeasure for this, and can replace the ions lost with ions from our saliva, in a process known as remineralisation. However, sometimes the rate at which this replacement occurs is below that at which the ions are being lost. When this happens the pores in the tooth can become enlarged, and cavities and tooth decay can result.
Where does fluoride come from?
Fluoride also occurs naturally in the majority of natural water supplies; often, this is at a lower concentration than that recommended, but in a select few places it can be much higher. For example, in some lakes in Ethiopa, levels of over 260mg/L have been recorded.
What is the name of the condition where fluoride is ingested and passes through the body?
Another form of fluorosis is often cited when discussing fluoridated water – skeletal fluorosis. This occurs when fluoride is ingested, and passes through the body, reacting with hydroxyapatite in the bones to form calcium fluoride.
Which is stronger, fluoride or hydroxyapatite?
They can be incorporated into the hydroxyapatite structure, replacing the hydroxide ions and forming fluorapatite. Fluorapatite is stronger than hydroxyapatite, and is also more resistant to acidic conditions.
How much fluoride is in black tea?
If we’re going to cover all bases, tea and some foods also contain fluoride; in fact, black tea can contain more than any artificially fluoridated water supply, and can be up to 2mg per litre. But even if you binge on tea all day, you’re unlikely to reach the lower bound of the 10-20mg per day figure.
What is the ionic compound that is made of calcium ions, phosphate ions, and hydrox?
This is known as demineralisation.
Which countries fluoridate their milk?
Aside from those that do practise some degree of artificial fluoridation, such as Spain, the UK, and Ireland, many other countries fluoridate their salt instead. Germany, Switzerland and France all do this, whilst in some countries in Eastern Europe, milk is fluoridated instead.
Overview
Implementation
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.
• Sodium fluoride (NaF) was the first compound used and is the reference standard. It is a white, odorless powder or crystal; the crystalline form is pref…
Goal
The goal of water fluoridation is to prevent tooth decay by adjusting the concentration of fluoride in public water supplies. Tooth decay (dental caries) is one of the most prevalent chronic diseases worldwide. Although it is rarely life-threatening, tooth decay can cause pain and impair eating, speaking, facial appearance, and acceptance into society, and it greatly affects the quality of lif…
Evidence
Existing evidence suggests that water fluoridation reduces tooth decay. Consistent evidence also suggests that it causes dental fluorosis, most of which is mild and not usually of aesthetic concern. No clear evidence of other adverse effects exists, though almost all research thereof has been of poor quality.
Reviews have shown that water fluoridation reduces cavities in children. A con…
Mechanism
Fluoride exerts its major effect by interfering with the demineralization mechanism of tooth decay. Tooth decay is an infectious disease, the key feature of which is an increase within dental plaque of bacteria such as Streptococcus mutans and Lactobacillus. These produce organic acids when carbohydrates, especially sugar, are eaten. When enough acid is produced to lower the pH belo…
Alternatives
The views on the most effective method for community prevention of tooth decay are mixed. The Australian government review states that water fluoridation is the most effective means of achieving fluoride exposure that is community-wide. The European Commission review states "No obvious advantage appears in favour of water fluoridation compared with topical preve…
Worldwide prevalence
As of November 2012, a total of about 378 million people worldwide received artificially fluoridated water. The majority of those were in the United States. About 40 million worldwide received water that was naturally fluoridated to recommended levels.
Much of the early work on establishing the connection between fluoride and d…
History
The history of water fluoridation can be divided into three periods. The first (c. 1801–1933) 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, f…