The fluoridation of public water sources has been carried out in cities throughout the United States for decades while debates surrounding the benefits and dangers of the practice continue to transpire.
While both sides of the fluoridation discussion have legitimate reason to support their claims, it is important to be able to separate truth from conjecture.
This article aims to highlight facts about the compound fluoride and the fluoridation process as well as bring to light the greater picture of how fluoridation came into the public scene.
We will also discuss whom and for what reasons one would want to remove fluoride from their drinking water source, and the most effective methods to do so. We will also discuss how to test for fluoride in water.
This article will discuss the following:
- A Chemical Explanation of What Fluoride Is and What it’s Used For
- The Benefits and Dangers of Fluoride
- A History of How Fluoride Was Added to the Water Supply
- How to Test for Fluoride In water
- How to Remove Fluoride from Water Effectively
Best Filters for Removing Fluoride from Water Supply
What is Fluoride?
Before discussing how to remove fluoride from water effectively, it is important to understand what Fluoride is.
Fluoride is a compound of Fluorine (F), the 13th most abundant element in the earth’s crust which derives its name from the Latin word “fluere”, which means, “to flow”.
A negatively charged Fluorine atom is known as Fluoride and can exists as several different compounds including Calcium Fluoride and Sodium Fluoride.
Fluoride exists naturally in surface water in varying levels depending on the region but usually doesn’t exceed concentrations of 0.3 ppm. Concentrations are much higher in groundwater and certainly in ocean water which can reach levels of up to 1.0 ppm.
As water moves through rocks and sediment, fluoride is collected and dispersed throughout various water sources on the earth. Regions including Pakistan, China, and Sri Lanka can typically have higher concentrations of naturally occurring fluoride in the groundwater than in the United States. However, historically, certain instances such as in Colorado in the early 1900s, proved to have extremely high concentrations of fluoride in the groundwater supply ranging from 2 to 13.7 ppm.
What is Fluoride Used For?
Fluoride is used in over-the-counter supplements, medical imaging, cleaning agents, and to make aluminum and Teflon products. But Fluoride is perhaps most widely known for its association with dentistry.
Fluoride, in the right dosage, can remineralize weakened tooth enamel, reverse early stages of tooth decay, and prevent the growth of bacteria which leads to cavities. It is used in toothpaste, mouthwash, and can be applied topically as a foam or varnish.
The discovery of the benefits of Fluoride is considered a landmark achievement within the dental industry and is widely used for cavity prevention today.
Known Dangers of Fluoride
While fluoride is certainly a major factor in modern cavity prevention, it is not without its health concerns especially in higher doses. The following are some of the health problems that can occur due to excessive fluoride intake.
Dental and Skeletal Fluorosis
Too much exposure to fluoride can result in fluorosis, an accumulation of excessive amounts of fluoride in the bones and teeth.
Dental fluorosis is accumulation of fluoride within the teeth and will result in chalky white stains on the surface. While dental fluorosis is aesthetically unappealing, it isn’t necessarily harmful to the teeth itself, but may be an indication of excessive fluoride intake within the body.
Skeletal fluorosis occurs at much higher levels of exposure to fluoride and is a much more serious concern. Bones can become hardened, less elastic, and more prone to fractures. If fluoride continues to accumulate in the bones, bone tissue will continue to grow, resulting in pain and impaired joint mobility.
Excessive fluoride exposure can also result in hyperparathyroidism, a disease of the parathyroid gland resulting in uncontrolled secretion of the parathyroid hormones.
Eventually, this can result in higher concentrations of calcium in the blood stream and a depletion of calcium in the bones.
Lower IQ - According to a report published by the Environmental Health Perspectives in 2017, a study was conducted on children between the ages of 6 to 12 in relation to the amount of fluoride they were exposed to. The study concluded that higher levels of fluoride exposure were linked to lower IQ scores.
Developmental Delay - Another study published on Lancet Neurol in 2014 concluded that increased exposure to fluoride can result in stunted cognitive development in children.
ADHD – A study published in the Environmental Health Journal reports that exposure to fluoridated water is linked to increased cases of Attention Deficit Hyperactivity Disorder in the United States among children and adolescents.
Toxicity From Industrial Waste
These synthetic fluoride compounds are categorized as toxins according to several agencies such as the U.S. National Library of Medicine and the United Nations.
A report published by the Journal of Environmental and Public Health in 2014 reported that synthetic fluoride in the blood during lifelong consumption can harm the heart, bones, and the brain.
History of Fluoridation in the United States
In order to better understand the current state of affairs of public fluoridation, it helps to take a step back and view the issue from an historical perspective. Perhaps by gaining insight into the origins of the discovery of fluoride, the motives of those involved on both sides of the equation today might make more sense.
An Accidental Discovery
In 1901, a dentist named Frederick McKay made a strange discovery in Colorado Springs, CO where he witnessed a high number of adults and children with peculiar brown stains on their teeth. Most of the residents of Colorado Springs where relatively healthy and McKay could find no evident reason for ailments of the mouth.
For several years after, McKay continued to speculate as to the origin of the “mottled teeth” of these otherwise healthy residents and in 1915, collaborated with the dean of the School of Dentistry at Northwestern University to investigate further.
In 1927, McKay’s research led him to strongly believe that the brown stains were linked to minerals in the drinking water but his laboratory tests couldn’t produce any conclusive evidence.
Gaining traction for his relentless pursuit of the mystery of stained teeth, the Public Health Service requested that McKay investigate the stained teeth of the townsfolk of Bauxite, Arkansas in 1931. It wasn’t until chief chemist of the Aluminum Mining Company of America (ALCOA), H.V. Churchill, in collaboration with McKay, used much more sophisticated instruments to determine that the source of the stained teeth is an extremely high concentration of fluoride (13.2 ppm) in the drinking water. This excessive exposure to fluoride, known as dental fluorosis, causes mottling of the teeth, an apparent aesthetic defect. But, perhaps the most interesting part of this discovery is the fact that those who were exposed to fluoride also had remarkably fewer cavities than most.
A Revolution in Dentistry
Because tooth decay was, at the time, a widespread problem throughout the United States which led to and complicated a host of other diseases, and which there seemed to be no effective remedy for, the discovery of fluoride in mitigating tooth decay was largely considered one of dentistry’s greatest achievements.
Thus, through years of further laboratory testing and extensive legislative exchange, it was determined that the therapeutic level of concentration of fluoride in drinking water, so as to provide the benefits of cavity protection yet avoid the dangers of fluorosis, should be 1.0 ppm.
The Birth of Public Fluoridation
While opposition for fluoridation among skeptics quickly arose, the push for local governments to immediately begin fluoridating the public water supply also quickly gained traction.
John Frisch, prominent member of the Wisconsin Dental Society and chief supporter of public fluoridation, through several years of diligent campaigning, succeeded in convincing the city of Madison, Wisconsin to begin fluoridating the public water supply.
With the endorsement of the Public Health Service and the American Dental Association, and the eagerness of other local governments to follow suit in fluoridating their own water supply, it seemed as though fluoridation would shortly become mainstream. And with a new fluoridation industry looming on the horizon, the demand for industrial fluoride became apparent.
To solve the problem of the expense and difficulty in producing large quantities of fluoride at the level which local governments required, Frisch inquired with ALCOA, the same company who in 1931 discovered the link between fluoride and the mottled teeth mystery. ALCOA, a leader in the aluminum industry, apparently produces vast amounts of fluoride as a byproduct of their aluminum production – amounts capable enough of supplying large cities with it.
Ongoing Controversy on Fluoridation
While the fluoridation of public water supply is widely considered a safe and even beneficial practice by medical professionals and government agencies, debates as to the legitimacy of these health claims and the denial of danger continue to occur to this day.
Rather than posturing onto either side of the fluoridation debate, this article aims to present the facts as objectively as possible.
What We Do Know About Fluoride
The following points are largely accepted by both proponents of the fluoridation discussion and are readily verifiable.
Fluoride Prevents Cavities
Fluoride, in adequate concentrations, remineralizes tooth enamel, reverses tooth decay, and prevents cavity-causing bacteria from growing. It is widely used in the dental industry for oral care.
Fluoride Exists Naturally in Water
As the compound Calcium Fluoride (CaF2), fluoride exists naturally in surface water, groundwater, and oceans throughout the earth in varying concentrations.
Fluoride is Released into Drinking Water
Cities throughout the United States have sodium fluoride added to their water supply in concentrations less than 0.7 ppm. Sodium fluoride (NaF) is a synthetic fluoride compound that is a byproduct of aluminum production.
High Doses of Fluoride Are Toxic to Humans
At high concentrations, fluoride, whether it be calcium fluoride or sodium fluoride, can cause a host of health problems including thyroid, bone, and brain damage.
Points of Contention
The following points highlight where debates about fluoridation often take place. Most of these points each have evidence that supports both sides of the discussion but aren't universally agreed upon.
Topical Benefits vs Systemic Benefits
Scientists of varying backgrounds disagree as to the route at which fluoride contacts the body that is most beneficial. Supporters of fluoridation claim that the benefits of fluoride can be experienced through topical application as well as through internally ingesting fluoride through one’s digestive system. Opposers of fluoridation claim that the cavity preventing qualities of fluoride are only applicable topically and that ingestion of fluoride has no dental benefit at all.
What Happens to Fluoride When Dissolved in Water
It’s largely uncontested that calcium fluoride which exists naturally in water is less toxic than the synthetic compound sodium fluoride. It’s also largely uncontested that sodium fluoride and the very highly toxic compound fluorosilicic acid, which are byproducts of industrial waste, are the main chemicals used in the fluoridation of public water supplies. The point of contention comes when discussing what happens to these chemicals when they interact with water. These fluoride compounds are soluble in water and generally break down depending on the alkalinity and TDS of the water.
Supporters of fluoridation argue that the solubility of these toxic chemicals render them harmless once they dissolve in water, and when it’s absorbed into the body, the body doesn’t recognize the former state these chemicals were in, toxic or not. The body simply recognizes the fluoride molecule and utilizes it as such.
Opposers of fluoridation are skeptical of the claim that these highly toxic chemicals are rendered harmless in water, and that the solubility is dependent on a number of factors such as water alkalinity, total dissolved solids, and the amount and concentration of chemicals introduced. Opposers are hesitant to believe such claims and would rather avoid fluoridation altogether.
Suspicion of ALCOA
Opposers of fluoridation point to the involvement of ALCOA in the fluoridation discovery claiming that their actions are highly suspicious in the grand scheme. While most don’t deny the cavity-prevention benefits of fluoride, some find it strange that the company who discovered the link between fluoride and dental care is the same company who happened to have large quantities of synthetic fluoride ready to be disposed of.
EPA Changing Recommended Fluoride Levels
In 2015, the US government set the new recommended amount of fluoride in public water systems to be no higher than 0.7 ppm, a 0.3 drop from the previous standard of 1 ppm. The official claim was that cases of fluorosis among children across the country remained relatively high, and the lowering of fluoride levels would mitigate these cases. Opposers of fluoridation claim that the government issuance of a lower threshold is evidence that the dangers of fluoridation are becoming more evident.
How to Test for Fluoride in Water
In order to determine the amount of fluoride present in your water supply, a fluoride test will need to be conducted. Fluoride tests work by measuring the level of fluoride molecules in the water in parts per million, or ppm. The measurement ppm is also equivalent to milligrams per liter (mg/L).
Tests can either be conducted by a water testing laboratory or with a personal testing device.
Laboratory Testing Services
For the most comprehensive results available, a water testing laboratory will need to be contacted. Most water testing laboratories will provide sample containers which will need to be filled with water straight out of the faucet. The sample will then be mailed back to the laboratory with the address and packaging provided.
After receiving the sample, the lab will run various tests with their own in-house equipment to determine the exact level of fluoride present in the water. Turn-around for test results will vary but most should expect to have their results back within several days.
Laboratory services are the most accurate way of determining fluoride levels in the water.
Home Fluoride Test Strips
The quickest, least expensive, and most convenient way to test for fluoride is to use test strips. Fluoride test strips work by dipping a paper strip into a glass of water and matching the color produced from the strip with a color chart provided. The color will indicate the level of fluoride present.
The downside to using test strips is that they aren’t nearly as comprehensive as a lab test and will typically only indicate levels at intervals of whole numbers. Thus, fluoride test strips are better for revealing a rough estimate of fluoride levels.
The Baldwin Meadows test strips test for fluoride between 0 to 5 ppm as well as 13 other parameters including lead, iron, and pH.
For those who require an immediate, accurate reading, a test device such a photometer or colorimeter may work best. Photometers use electronic sensors to test the fluoride ions in the water and show the results on a digital screen. Colorimeters use chemical solutions to react with the fluoride in the water, changing the color of the solution which is then matched with a color chart.
Fluoride testing meters are more expensive than test strips but far more accurate.
The Extech fluoride meter is a lightweight, portable testing meter which uses electrodes to test for fluoride in the water. It features an LCD screen for showing results and provides readings within 1 minute of testing. Tests for fluoride within 0.1 to 10 ppm.
How to Remove Fluoride in Water
As the disagreement about the necessity of fluoridation continues, some may have reasons to avoid fluoride intake altogether. This section of the article will focus on the most effective ways of removing fluoride from the home water supply.
Because fluoride ions are microscopic in size, a standard carbon filter will be ineffective in removing fluoride from water. Fluoride ions must be addressed at the chemical level in order for effective removal to take place.
One of the most effective and most practical methods for removing fluoride from a home water supply is to install a reverse osmosis system.
Reverse Osmosis works by using pressure to force water through a permeable membrane which only allows water molecules to pass through. The end result is a concentration of water which is absent of any molecule other than H20. All other contaminants, minerals, and ions are unable to pass through the membrane.
Because water which has been treated through reverse osmosis lacks any minerals, the water can have a slightly lower pH and can taste flat. Many RO systems include remineralization filters which add minerals back into the water, raising the pH levels and improving the taste.
RO systems can be installed under the kitchen sink which treats the water just before it exits the faucet or installed as a whole house system.
Activated alumina, better known as aluminum oxide, is a compound found in sapphires and rubies but without the impurities that give these gemstones their distinct color. With its high surface-area-to-weight ratio, activated alumina has a very high capacity to absorb fluoride and is recommended by the EPA as an effective medium in removing fluoride, arsenic, and thallium.
In order for activated alumina to be effective, the water must have pH at 6.5 or lower and for proper absorption to occur.
While many fluoride filters use activated alumina as its primary medium for fluoride removal, it is important to note that activated doesn’t remove 100% of fluoride from water but reduces it to a much safer concentration – around 0.1 ppm.
Bone Char Carbon / Brimac Char
Bone Char, also known as Brimac Char, is one of the oldest methods for fluoride removal in the United States. Made from finely crushed cattle bones which are heated, bone char has a very high absorption capacity for fluoride and many other contaminants including lead, arsenic, and cadmium.
Like activated alumina, bone char has a very porous ionic surface, making it extremely efficient in absorbing both inorganic and organic materials, especially fluoride. Also like activated alumina, bone char filtration works best at a slightly acidic pH level and a lower flow rate to ensure better absorption.
Bone char comes in the form of filter cartridges and will remove fluoride up to 90% of fluoride depending on the quality of the bone char and the frequency at which the filters are replaced.
Bone char, along with activated alumina and reverse osmosis, is one of the 3 methods the EPA considers to be the most effective ways to remove fluoride from water.
The oldest, least expensive method for purifying water is through distillation. Like the earth’s hydrologic cycle, distillation works through the natural processes of evaporation and condensation.
As fluoride-concentrated water is heated, steam evaporates from the boiling water and condenses onto a surface. The condensation the collects into a new container, leaving the fluoride and other contaminants behind. The end result is pure, distilled H20.
Like reverse osmosis, the process of distillation removes more than just fluoride but particles and ions altogether, leaving the water empty of minerals and slightly acidic. Remineralization is advised in order to raise the pH level and improve the quality of taste.
Home countertop distillation units can be purchased for convenient distilling whenever needed. Because of the relatively slow rate at which water is distilled, distillation units are more practical for individuals or small families.
The Best Water Filters for Removing Fluoride
With reverse osmosis, distillation, activated alumina, and bore char as the most effective methods of removing fluoride from water, the following is a list of the best filters which use these methods.
- 5 Stages
- Sediment Filter
- 1st Carbon Block
- 2nd Carbon Bloack
- RO Membrane
- Refining Carbon Filter
- Pressure: 45-70 psi
- 90 Gallon per day capacity
- 2 Year Warranty
- Made in the USA
The RO-90 by APEC is a popular reverse osmosis system among homeowners, receiving great reviews for its build quality and APEC's excellent customer support.
The RO-90 features a sediment filter, 2 carbon block filters, a refining carbon filter to polish the water's taste, and the RO membrane, the filter responsible for blocking fluoride ions.
The APEC RO-90 comes with a lifetime of support and 2-year warranty.
More models by APEC:
- APEC 5-Stage Reverse Osmosis (ESSENCE ROES-50)
- APEC 3-Stage RO System WFS-1000
- APEC 6-Stage RO Filter System (ESSENCE ROES-PH75)
- APEC High Output Fast Flow RO Drinking Water Filter System
- APEC Essence Series UV 7-Stage RO System ROES-PHUV75
- APEC pH+ High Output 90 GPD 6-Stage RO System (ULTIMATE RO-PH90)
- Uses Activated Alumina and Carbon
- Removes Fluoride, Lead, Chlorine, Chemicals, Heavy Metals
- 12,000 Gallon Filter Capacity
- 3 Year Warranty on Cartridge
Crystal Clear's activated alumina and carbon filter blend removes fluoride while leaving important minerals such as magnesium and calcium in the water.
The alumina alumina and carbon blend filters out fluoride, lead, chlorine, and heavy metals from the water supply, ensuring safe, clean water for drinking.
The filter installs under the kitchen sink and comes with a long neck faucet for dispensing water.
Crystal Clear offers a 3 year warranty on the filter cartridge and a 5 year warranty for all components.
As with all activated alumina filters, water must have a slightly lower pH in order to work effectively.
- Distills 1 Gallon every 5.5 hours
- UL Listed and Approved
- 1 Year Warranty
- Activated Carbon Filtration
- 304 Grade Stainless Steel
- Automatic Shut-off
The Megahome Countertop Water Distiller has been on the market for 22 years and remains the most widely distributed countertop distiller in the world.
It distills water at a moderate speed – 1 Gallon per 5.5 hours. With an efficient cooling system and activated carbon filter, this distiller will provide fluoride-free water in a 4L glass carafe. It features an automatic shut-off as a safety featuring for overnight distilling. With a one-year warranty, this distiller offers much in terms of quality and security.
- Activated Alumina and Bone Char Blend
- Removes Fluoride, Arsenic, Chlorine, Herbicides, and Pesticides
- High Flow Rate
The 3 -stage Big Blue filter by Abundant Flow Water uses an activated alumina and bone char blend to remove fluoride and arsenic from the water supply.
The first stage is a polypropylene sediment filter to block small gravel and debris that may enter the filter.
The second stage is the activated alumina and bone char filter which removes the fluoride.
The final stage is a radial flow carbon filter which removes chlorine, pesticides, and herbicides.
Fluoride is compound of the element Fluorine and is used in dentistry for restoring tooth enamel and reversing cavities. The discovery of fluoride is, in fact, considered one of the most significant achievements in dental history.
While fluoride does have its benefits for tooth care, excessive fluoride exposure can cause health problems such as fluorosis and thyroid problems. Furthermore, synthetic fluoride from industrial waste, and the main type of fluoride used in public fluoridation, is toxic to humans.
Due to the controversial history of public water fluoridation, debates as to the safety of fluoridation continue to occur, and both sides of the debate have compelling evidence to support their claims.
For those who have reason to want to remove fluoride from their water supply, there are several ways to do so. Reverse osmosis, distillation, activated alumina, and bone char are some of the most effective ways of removing fluoride from the drinking water supply.
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