Reverse osmosis and nanofiltration are two examples of high-pressure membranes that have proven to be very efficient at eliminating PFAS. Nanofiltration membranes are looser than reverse osmosis membranes.
How Can PFAS Be Filtered Out Using Reverse Osmosis?
Water is forced through a semi-permeable membrane via reverse osmosis filters. Since the pore size of this membrane is approximately 0.0005 microns, any pollutant larger than this micron rating will not be able to pass through the membrane with water particles.
RO is a good choice for eliminating this contamination because the typical PFAS molecule is substantially larger than 0.0005 microns.
The RO membrane deflects pollutants including PFAS, PFOA, and PFOS when they hit it. A tiny amount of water is flushed down the drain in the chamber that houses the RO membrane during the RO process. By doing this, a buildup of pollutants in the RO chamber is avoided.
Along with the RO membrane, a typical RO system will also contain various filtration stages. One of these filters, the carbon filter, can get rid of about 73% of the PFAS in water. The most efficient overall PFAS removal solution combines the RO membrane and carbon filter.
What Portion of PFAS Does RO Remove?
You should be able to lower your PFAS levels to below the Environmental Protection Agency’s health recommendation level of 70 parts per trillion with the help of reverse osmosis because it is so thorough and can remove more than 90% of all PFAS contamination. If you want to use an at-home filtration system to eliminate PFAS, PFOA, and PFOS from your water, this is about as good as it gets.
What Else Are Removed from Drinking Water by Reverse Osmosis Filters?
There’s a strong probability that in addition to worrying about PFAS contamination in your water, you’re also worried about other toxins. With up to 99.9% efficacy, RO can eliminate impurities like chlorine, germs, viruses, heavy metals, fluoride, VOCs, minerals, salts, and medicines.
It’s simpler to state what reverse osmosis systems don’t remove: certain solvents, VOCs, and pesticides may still be present in your water after using RO water filters, and hydrogen sulfide and other dissolved gases may be able to pass through the RO membrane.
Restrictions on RO systems
Although PFAS and other dangerous drinking water contaminants can be effectively removed by RO systems, there are several drawbacks to be aware of.
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Costlier Price
You should prepare to pay more for this form of water treatment solution because RO is so capable. An RO system typically costs more than $300, and that doesn’t include yearly maintenance fees.
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Filtration Process Leads to Wastewater Production
Your RO system will lose some water during the water treatment process regardless of whether you are utilizing point-of-entry (such as whole-house systems) or point-of-use filters. Unfortunately, there is no way to avoid this, even though newer systems are much more effective than older ones.
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Removed Healthy Minerals
Although RO water treatment is undeniably quite advantageous, a significant drawback is that these water filters also remove important minerals from tap water. You must find a device with a remineralization water filter or buy mineral drops if you wish to add these minerals back into your water.
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upkeep to keep up with
Last but not least, routine filter cleaning and replacement is required for RO water purification. This upkeep is necessary if you want your RO system to keep performing at a high level.
Minerals are absent from reverse osmosis water.
Buying a Reverse Osmosis System: Things to Bear in Mind
Be sure to keep the following things in mind when searching for a RO system:
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Produced Water to Wastewater Ratio Efficiency
All RO filters produce some wastewater, as I already indicated, although some produce more than others. Nowadays, there are RO systems available that only waste 2 gallons of water for every gallon of clean water generated, as opposed to the older RO systems that used to waste 4 gallons.
If you want to waste as little water as possible, some systems even have a 1:1 wastewater-to-pure water ratio that would be worth looking into.
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The Water Quality in Your Home
When deciding which system is best for you, keep in mind the quality of your drinking water, including the chemistry and toxins present. Your RO system will have to work more difficult the more impurities there are in your water.
Your RO membrane will handle whatever it encounters, even if all you want to do is get rid of PFAS chemicals. Your filters and membrane will likely need to be replaced more frequently than the manufacturer suggests since they will clog up more quickly.
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System Type
There are numerous RO system varieties to pick from. If you just want to eliminate PFAS from the drinking water coming from your faucet, point-of-use filters, such as the under-sink reverse osmosis filter, are the most popular choice.
Comparatively speaking, point-of-use units are easier to find than whole-house systems. Even while research has shown that whole-home treatment may make your pipes and plumbing more prone to bacterial development, the advantages of whole-house filtration are unquestionably worthwhile to take into account.
Lastly, countertop RO systems are also excellent at lowering the concentrations of PFAS in water. With so many different RO treatment options available, you’re sure to discover one that works best for you.
No matter which option you choose, RO systems all remove around the same amount of toxins, therefore RO treatment is the best option if you want to prevent the negative effects of PFAS on your health.
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Your Budget
Your ability to purchase a certain filtering system will depend on your budget. Some solutions, including whole-house systems, can be out of your price range.
Additionally, more expensive RO systems, tankless systems, and systems with more than four phases are typically required (which is pretty much the average for an RO water filter). The under-sink, tank-based RO system is the most cost-effective choice.
You’ll need at least $200 to $300 to get a long-lasting, high-quality system. Avoid the temptation to save money by purchasing a subpar system because it might not even be effective at removing PFAS, which is the main reason you want to buy one.
ALSO SEE: Does Activated Carbon Remove PFAS?
Alternative Consideration: Activated Carbon Filters
An excellent RO substitute if you don’t think your budget will allow it is activated carbon.
High concentrations of PFAS compounds can be removed using activated carbon filters (by about 73%). The main benefit of these filters is that they are far less expensive than RO filters, even though they might not be quite as effective at removing these impurities.
Nevertheless, it does matter what kind of activated carbon filter you purchase. Systems evaluated showed a wide range of performance; some filters removed a lot of PFAS from drinking water, while others removed almost none.