A whopping 73% of people in the USA drink fluoridated water everyday from their faucets. Yet, there are only a few types of water purifiers that can actually remove fluoride from water – and it’s not the ones you might think. In fact, it’s not your usual home water purification systems that will successfully remove fluoride.
Anion exchange (activated alumina), distillation and reverse osmosis are the only methods of water purification that can successfully remove fluoride from water. All other water filtration and purification systems are unable to remove fluoride.
This means that most of water purifiers available on the market don’t remove fluoride. Especially, the filters and purifiers that use activated carbon to remove contaminants – as it has no effect on fluoride!
So, keep reading to learn where the fluoride in our water comes from and which water purifiers remove fluoride from water.
Can water purifiers remove fluoride?
Fluoride can be in our drinking water because of erosion from natural rock deposits. Although, it is usually found in our water because community and public water systems purposefully add fluoride to our drinking water.
Unlike some other things in our water, fluoride does not change the way that water looks, smells or tastes. That means you can’t tell if fluoride is in your water or not.
Some people do not like fluoride in their water and would rather get their fluoride from natural sources, such as foods like grapes. While other people are concerned that their water filters are already removing the fluoride and they don’t even know it!
The 3 types of water purification that can remove fluoride from water are:
- Anion exchange
- Reverse Osmosis
Keep reading to learn HOW they remove fluoride:
1. Anion exchange
Ok, so what does anion exchange even mean? Well, fluoride is an ‘ion’, and water purification by ‘anion exchange’ means the fluoride ion is exchanged with another ion (usually a hydroxide ion – a natural and normal constituent of water) on the surface of a certain type of filter.
In the case of fluoride, the filter has to be activated alumina (or granulated activated alumina) for the fluoride ion to exchange. The fluoride builds up on the surface of the filter, while the de-fluoridated water flows through, ready for you to drink.
Something else to consider, is the fact that activated alumina will only remove fluoride at optimum pH levels. So if your water is more alkaline than 8.1pH – which can happen if you have hard water (water with high mineral content), then anion exchange may not remove fluoride from your water.
Hopefully, that didn’t sound too much like a chemistry lesson in school! The important thing to know is that to remove fluoride by anion exchange, you need an activated alumina filter.
A standard distillation system purifies water by heating and evaporating the water, before cooling the vapor and capturing it for you to drink. This treats water, because it leaves behind all the nasty things that didn’t evaporate, such as bacteria and heavy metals.
This also includes fluoride.
The National Sanitation Foundation (NSF) only certifies three forms of fluoride for use as drinking water treatments. The three forms of fluoride that carry NSF certification 60 (NSF-60) and are added to our drinking water are:
- Sodium fluoride
- Fluorosilicic acid
- Sodium fluorosilicate
The boiling point of sodium fluoride is 3,099 degrees Fahrenheit, and for fluorosilicic acid it is 227.3 degrees Fahrenheit. Because their boiling points are above that of water (212 °F), when the water evaporates the fluoride is left behind. Sodium fluorosilicate does not have a boiling point but it decomposes at 932°F, so it is also removed from the water as it evaporates at 212°F.
Distillation is certainly an effective method at removing fluoride from water!
3. Reverse Osmosis
Reverse osmosis systems are able to remove fluoride from water because of the semi permeable membrane, and not because of its other filters.
The reverse osmosis system applies pressure from the side of the untreated water and pushes the water through the membrane. As the water flows through the membrane, the fluoride ion is left behind.
Even though the semi permeable membrane removes the fluoride from your tap water, you can actually buy activated alumina cartridges that will fit most whole house reverse osmosis systems. So if you really want to be sure that there is no fluoride in your drinking water you could double-up and enhance your reverse osmosis system with anion exchange!
Because of the high-energy costs involved with distillation, and the limited pH range of activated alumina, reverse osmosis is considered the cheaper and more effective method for fluoride removal.
Just remember that most semi permeable membranes need replacing every 1-2 years. Make sure to check how often your membrane should be replaced and keep a good cleaning and maintenance schedule to ensure your reverse osmosis system is purifying your water effectively.
Other ways to remove fluoride?!
While anion exchange, distillation and reverse osmosis are the only ways to truly remove fluoride from your water, there have been some other weird methods that remove some fluoride – but certainly not all! They typically involve adding something to your water (which you then have to remove anyway).
By adding one of the following odd things to your water you can partially remove fluoride:
- Aluminium salt
- Bone char
- Magnesium carbonate
- Soda ash
However, if you want to properly remove fluoride from your water, or if you want to know if your water purifier is already removing it – Here is a table showing you exactly which water purifiers do and do not remove fluoride from water:
|Purification Method||Type of Purifier||Removes Fluoride|
|Anion exchange |
(Activated alumina filter)
|Under the counter||✓|
|Under the counter||✓|
|Under the counter||✗|
|Under the counter||✓|
|Ultrafiltration||Under the counter||✗|
|UltraViolet||Under the counter||✗|
Still interested and want to know more about how activated alumina removes fluoride from water? Well, the EPA has generated a manual on the removal of fluoride from water – if you don’t have access to it you can find it here.
Do refrigerator water filters remove fluoride?
Refrigerator filters are not able to remove fluoride from water. Most refrigerator and icemaker filters use carbon and/or sediment filters to treat water. Carbon and sediment filters are unable to remove fluoride, or other mineral ions like magnesium.
How to remove fluoride from water without a filter
The only way to remove fluoride from your water at home without a filter is distillation. Distillation will purify your water and remove the fluoride at the same time.
Water distillers heat water above boiling point and then cool and condense the water vapor, to make it ready for drinking. Because fluoride doesn’t boil at or below the temperature that water boils at, it is left behind – removed from your drinking water.
There is counter-top and under the counter distillation systems you can use to remove fluoride from your water without a filter.
Does lemon remove fluoride from water?
Lemon does NOT remove fluoride from water. It has been suggested in the past that citric acid (a component of lemon juice) can remove fluoride from water – this is not the case!
But, adding lemon to your water can certainly make it taste nice!
Why is there fluoride in tap water? Fluoride is added to our drinking water supply to promote strong teeth. Fluoride addition is typically 0.7mg/L to the public drinking supply and reduces tooth decay. While, the EPA mandates that the fluoride cannot exceed 4mg/L (or ppm). Read more about why Fluoride is in tap water here.
What are the benefits of fluoride in water? According to the CDC, fluoride helps prevent tooth decay and cavities, reduces pain and makes teeth stronger. Fluoride combines with calcium and phosphate in your teeth to form fluorapatite, which is much stronger for your teeth and makes them more resistant to decay. In fact the CDC says, “drinking fluoridated water strengthens teeth and reduces tooth decay by about 25% in children and adults”.