What Kind of Water Filter Removes Fluoride from Drinking Water?

Fluoride salts form naturally when fluorine gas reacts with metals and other positively charged ions. They are found in water, rocks, air, and soil at different concentrations worldwide and are also present in some foods and toothpaste. Additionally, fluoride is added to water (fluoridation) to help prevent tooth decay or dental caries.

A reverse osmosis (RO) filter is the most effective in removing excessive fluoride from water and can be easily and inexpensively installed in the home. Distillation also works well and can remove up to 99.9% of fluoride, but this also eliminates other minerals which may be beneficial to human health.

Read on to learn more about fluoride in water, how to remove it, and what DOESN’T remove it!

Is there a water filter that removes chlorine and fluoride?

Multistage filters that use different layers of filtration, including activated carbon, oxidation-reduction, and ion exchange, can all remove about 90% of both chlorine and fluoride from water. In addition to fluoride, chlorine is usually added to tap water as a disinfectant to kill microorganisms, and then some remains in the supply.

Although the water is safe to drink, chlorine leaves an unpleasant taste that most people do not like. Since chlorine is a gas, it eventually evaporates into the air, but there are also RO filters that incorporate activated carbon in them to draw it out faster.

Various technologies are used to reduce fluoride amounts in water using adsorbent materials to which the fluoride adsorbs. Adsorption technologies also differ in effectiveness based on how they are prepared and the conditions of the water such as pH (its acidity or alkalinity).

Adsorption is the process whereby particles bind to the surface of the adsorbent material as they collide with it.

Activated alumina  (aluminum oxide) is an example of an adsorbent material that can lower fluoride concentrations in water and provide between 85% to 95% efficiency of adsorption at a pH of 5.0. However, this may not be achievable since most household water treatment systems cannot control pH to the required levels.

As water containing fluoride passes through, the fluoride adsorbs onto the alumina.  An activated carbon filter can be used thereafter to remove bad tastes in the water from alumina treatment.

Alumina filters need to be replaced after some time as they get blocked with increased fluoride adsorption and other ions. The alumina can also be corroded if the water passing through it is too acidic, thus raising aluminum levels in the water.

Will a 5-micron filter remove fluoride?

Generally, any micro-filter with pore sizes ranging from 0.05 microns to 5 microns will not be effective in removing chemical contaminants, including fluoride and viruses.

On the other hand, microfiltration is highly effective against protozoa and moderately effective against bacteria.

Does carbon filter remove fluoride?

Carbon filters are not very good at removing fluoride from water.

A report published in the Journal of the Canadian Dental Association reveals that activated-carbon filters have a low absorptive capacity for fluoride ions. The absorptive capacity of coconut shell charcoal in domestic water filters for fluoride ions also differs from that of activated bone charcoal.

It concludes that carbon filters used in domestic water filtration systems do not remove fluoride.

Does bottled water contain fluoride?

Bottled water products may or may not contain fluoride, depending on the water source. Public water supply systems usually add fluoride to their water, but it can naturally be present in the source.

Unless indicated on bottle labels as a constituent, distilled, de-ionized, demineralized, and purified water products usually undergo treatments that can eliminate fluoride or leave very limited traces of it. In the United States, the Food and Drug Administration (FDA) considers the source of the water in addition to other factors in setting limits for fluoride in bottled water

Does boiling water remove fluoride?

No.

Boiling does not remove fluoride from water. However, boiling water for the purpose of distillation will work. In distillation, the water is brought to a boil, and then the steam from the water is captured and condensed back to water. Through this method, fluoride and other salts are eliminated completed from the water.

The downside is that distillation systems can be expensive, unsafe for home use, consume huge amounts of energy, and are cumbersome to maintain as salt deposits collect inside them.

However, boiling can still be an alternative to water filtration, especially in emergencies or when off-grid.  

Why should fluoride be removed from water?

Low fluoride levels in drinking water have been found to prevent tooth decay, which is why fluoridation is carried out on public water supplies. However, fluoridation must be kept in check because too much of it can cause health complications. Too much fluoride causes dental fluorosis, which leads to pitting or discoloration of teeth, enamel, and skeletal fluorosis, resulting in weak bones, stiffness, and joint pains.

Changes in bone structure, calcification of ligaments leading to muscle damage and pain, and impairment of the brain or nervous system can also be experienced after long-term ingestion. Abdominal pain, excessive salivation, nausea, vomiting, seizures, and muscle spasms are some of the symptoms of extreme overdose. There is no evidence, however, of serious effects of fluoride on the environment, plants, animals, and humans, or that it causes corrosion.

Final Thoughts

The amount of fluoride removed by a given filtration system will depend on the treatment process, system operational conditions, the water’s chemical composition, and the filter’s quality.

Though common, only specific carbon filters will remove fluoride, and even so, to a small extent. Distillation may be great, but it also strips the water of other important nutrients, such as calcium and magnesium, and can make it lose taste.

The NSF (National Sanitation Foundation) and ANSI (American National Standards Institute) are the bodies you can trust to vet and give water filters a clean bill of health.

If you get an NSF-certified RO system, you can rest assured that you will have water that is safe for drinking, food preparation, and other domestic uses.