How to Remove PFAS From Water (2024 Ultimate Guide)

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PFAS were big in the news several years back when they were found present in “toxic levels” in many bottled water sources. But PFAS exposure isn’t only limited to drinking bottled water. Your home’s public water or well water supply may also be laced with PFAS as a result of pollution in your local area.

In this in-depth guide, I’ll be looking at all things PFAS – their origin in the United States, the danger they present to human health, and how to remove them from your drinking water.

πŸ’‘ What Are PFAS (Per- and Polyfluorinated Substances)?

Per- and polyfluoroalkyl substances, PFAS in short, is a name that refers to a group of some 4,000 chemicals, which are characterized by their strong carbon-fluorine bonds.

These chemicals were used in factories, military bases, airports and industrial sites in the United States for nearly a century – until it was discovered that the chemicals were being released as byproducts into the air, resulting in widespread environmental pollution of the earth, the air, and natural water sources across multiple states.

Because PFAS chemicals can exist in the environment for a long time, research indicates that it’s highly probable that humans will be exposed to them.


There are two PFAS that are considered the most common and dangerous, and have now been phased out of use: PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid).

Both of these PFAS chemicals were traditionally used to produce a number of common consumer products, from non-stick kitchenware and paper to paints, cleaning products and stain repellents, food packaging, and water-resistant clothing.

Both chemicals have toxic bioaccumulation properties and are considered “forever chemicals”, meaning they could linger in the environment for hundreds of years on end.

🧯 Where Do PFAS Come From?

PFAS contamination largely results from human activity.

The main sources of PFAS chemicals are PFAS processing and manufacturing factories, and airports and military bases that use fire fighting foams that contain this chemical.

Products that contain PFAs

🚱 How Do PFAS Get Into Water?

There are several different ways that we can be exposed to PFAS – such as using products that contain PFAS or breathing in PFAS-contaminated air.

However, most commonly, PFAS contamination is a problem in water.

There are several ways that PFOA & PFOS may get into local drinking water supplies.

You may live in close proximity to a factory that produces or releases PFAS chemicals as a byproduct.

You may also live close to an airfield, military base or oil refinery, where PFOS or PFOA used in firefighting foam may contaminate water sources through surface runoff.

But surely, you’re thinking, these chemicals would be thoroughly removed from your water before it reached your home?

Don’t be so quick to assume.

A research team found that in 2016, at least 6 million people in the United States were drinking water containing PFAS levels that exceeded the EPA’s public health recommendations.

firefighting foam pfas

🩺 Health Risks Associated With PFAS

The EPA (Environmental Protection Agency) produced a non-enforceable health advisory level for the maximum contaminant level of PFOS and PFAS, stating that these chemicals shouldn’t exceed 70 parts per trillion, or ppt, in public water supplies.

However, lower levels of PFAS may still cause harm if consumed in drinking water.

Some of the common health risks associated with PFAS in drinking water include the following:


Research indicates that PFOA and PFOS in drinking may increase the risk of cancerous tumors, as PFAS contamination has been labeled as carcinogenic to the human body.

PFAS exposure has been linked in particular to testicular, kidney and liver cancer.

Immune System Effects

Studies conducted on animals found that PFAS exposure may reduce the immune system’s ability to respond to the threat of pathogens in the body, reducing resistance to disease.

Additionally, PFAS exposure may even prevent the body from producing the level of antibodies required in response to vaccination, which is particularly worrying in light of the COVID-19 pandemic.

Thyroid Hormone Disruption

A number of studies have found that PFOA and PFOS in the blood may disrupt endocrine function and prevent the thyroid from functioning properly.

According to the data we have so far, PFOS or PFOA may result in “accumulation, cytotoxicity, genotoxicity, interference with TH synthesis, TPO function, and iodine uptake” in the thyroid cells.

Low Birth Weight

One study found that if the parent or parents of a developing infant had high levels of PFAS in their blood, the infant was more likely to experience issues with preterm birth weight, with a higher likelihood of being small-for-gestational-age.

Not only was infant birth weight lower; the infant was also found to have stunted growth for the first two years of life. PFOA and PFOS have also been linked to a decreased likelihood of pregnancy in women.

πŸ§ͺ How to Test for PFAS in Water?

PFOA and PFAS are invisible to the human eye, and you won’t taste them or smell them in your water, either.

This makes them more dangerous, as if you were asked to choose between a glass of water that contained no PFOS and PFOA and a glass of water that contained dangerously high levels of these chemicals, you’d be none the wiser.

Before you look at how to remove PFOA from water, however, you need to be certain that your water actually contains it.

The best way to do this, considering contamination isn’t evidential to the eye, is to test your water.

The most effective way to get your water tested is to send off a sample to a state-certified laboratory.

The laboratory will thoroughly analyze your water and produce a detailed report that’ll tell you exactly how badly your water is contaminated with PFOS and PFOAs, measured in PPT (parts per trillion).

We Recommend: Tap Score by Simplelab

SimpleLab Tap Score

  • Tests for 14 of the most common PFAS
  • Tests concentrations down to below 2 PPM
  • 10 day turnaround time
  • Self-serve report on the website
  • Uses EPA testing method 537.1
  • Free shipping both ways

If you don’t want to get your water tested for PFOS or PFOA individually, or if you don’t know which of these chemicals your water may contain, it’s wise to test for them together.

State-certified laboratory testing usually costs somewhere within the range of $100 and $300 for a one-time test, so it’s not cheap, but getting your water tested may provide information that, when it comes to the health of yourself and your family, proves invaluable going forward.

Wondering if an at-home test kit is a good enough substitute for laboratory testing? I would advise against using this method alone if you have reason to be concerned about the PFOA and PFOS levels in your tap water.

While a testing kit can provide you with some basic information about your water quality and indicate whether your tap water contains PFAS, it won’t provide the level of depth you need to know whether your water is safe to drink or not.

βœ… How to Remove PFAS from Drinking Water

If you’re looking to remove PFOA and PFOS from tap water, there are a number of water treatment systems that are up for the job.

Activated Carbon Filters

Activated carbon filters, usually granular activated carbon or solid carbon block cartridges, are particularly effective at removing PFOA & PFOS from household drinking water sources.

According to the EPA, if you’re dealing with PFAS contamination in the United States, activated carbon filters are the first and most studied water treatment option to consider.

A granular activated carbon water filter adsorbs a number of common water contaminants, including chlorine, lead, and PFAS.

Being highly porous and with a large surface area, activated carbon naturally makes for an effective filtration option, trapping larger contaminants in the filter pores and allowing only smaller water particles to pass through.

Granular activated carbon can be 100% effective, according to an EPA researcher, for a limited period of time – and this depends on several factors, such as water temperature and flow rate, the depth of the carbon bed, and the types of PFAS you need to remove.

There are many different GAC treatment technologies you can choose from, but you’ll usually find a GAC filter in a whole-house application for well water or municipal water treatment.

The top under-sink, pitcher, and countertop filters are also options to consider.

Unboxing new black berkey filter elements

Ion Exchange Systems

Another water treatment solution for removing tap water PFAS is ion exchange. An ion exchange system consists of a tank containing an anion exchange resin, which is typically made from insoluble hydrocarbons.

There are two types of ion exchange resins: anionic resins and cationic resins.

Cationic resins are negatively charged, making them the better choice for removing positively charged impurities, while anionic resins, being positively charged, are effective at removing negatively charged impurities.

Both resin beds work like magnets, attracting specific contaminants, which stick to their surfaces and are unable to pass out of the tank with water particles.

PFAS are typically negatively charged, which makes anionic resins the best choice for removing PFAS.

This solution tends to have a higher capacity than activated carbon water treatment, but it comes at a higher upfront cost.

Like an activated carbon water filter, an ion exchange system can be highly effective in removing drinking water PFAS, but again, the effectiveness of the process may be determined somewhat by the flow rate and temperature of water, the depth and quality of the resin bed, the other contaminants in your drinking water, and so on.

anions and cations explained

Reverse Osmosis Systems

A reverse osmosis filtration system is typically considered one of the most thorough and wide-ranging water filters available on today’s market.

During the reverse osmosis process, water is sent at a high pressure through a semi-permeable membrane, which has tiny pores of around 0.0005 microns in size. While PFAS vary in size, they’re usually much larger than these membrane pores, and are unable to filter through with water particles.

A reverse osmosis filter can typically greatly reduce PFOA and PFOS; up to around 90%. The lingering PFAS, and hundreds of other trace contaminants in water, are released down a drain during the reverse osmosis process, so only pure water makes it to your faucet.

It’s worth knowing that reverse osmosis treatment does waste around 20% of water used in the filter process because of the system’s design.

Reverse osmosis filters may be point of entry – installed at your main water line to provide whole house filtration – or point of use – installed beneath your kitchen sink to provide clean, filtered drinking water.

Some RO treatment options are available as standalone countertop units that don’t require connecting up to your waterline at all.

It’s relatively easy to maintain reverse osmosis technologies. The filter cartridges require changing once every year or so, while the RO membrane usually lasts for 2 years before it needs replacing.

πŸ₯‡ Which Water Filters Are Best For PFOS and PFOA Removal?

Now you know your options, which system is the right choice for you?

It depends on what you’re looking for.

If you’re just after a treatment system that’ll remove PFAS, then carbon filtration or ion exchange systems may provide the ideal solution.

But if you like the idea of removing PFAS and purifying your drinking water, making it completely safe and minimizing health effects from a broad range of contaminants, reverse osmosis filters may be the better option.

Your budget will probably play a big part in your purchasing decision, too.

Read Our Reviews: The Best Water Filter for PFAs Removal in 2024

If you don’t want to spend big bucks on a top of the line water filter for PFAs, you may be somewhat limited in which systems are available to you.

Reverse osmosis filters tend to be the most expensive, while carbon filters are generally available in a broader range of options, with some being more affordable than others.

It’s essential that you carry out testing to know exactly which impurities your water is contaminated with before considering a contaminant removal solution.

Many whole-home filters and point-of-use treatment technologies can filter out more than just PFOS and PFAS.

Contaminants including lead, chlorine, arsenic and VOCs are all common in tap water and have their own maximum contaminant advisory level set out by the Environmental Protection Agency (EPA) due to their potential health effects.

It’s perfectly possible to tackle multiple contaminants in one go, and knowing what your water is contaminated with is undoubtedly useful.

Related: Do refrigerator filters remove PFAs?

❔ PFOS and PFOA Removal FAQ

What does it mean if a product is certified by NSF International for PFAS removal?

If a product has an NSF International 53 or 58 certification, it means it has been independently tested and deemed capable of reducing PFOA or PFOS to less than 70 ppt, as outlined by the Environmental Protection Agency. This is a great vote of confidence for you, the buyer, as you can be certain that a product is capable of whatever it’s advertised to do. Visit NSF’s certification listings to view the full list of products certified to remove PFOA and PFOS.

Are any other technologies capable of PFAS removal?

There are a few. For instance, distillation tends to be highly effective – even more so than a filter – at removing this chemical from water. But unlike the quick-fix solutions mentioned in this guide, a distiller could take up to 4 hours to produce a single batch of chemical-free water, so it’s far from a fast and easy clean water solution.

Will boiling water remove PFAS?

No, boiling water alone won’t remove PFOS and PFOA, as there’s no evaporation & condensation or filter process that could remove the chemical. In fact, boiling your water would just cause some of the water particles to evaporate, resulting in the same concentration of PFAS within a smaller batch of water.

How do I know if I’m at risk of PFAS exposure?

Your local state should have information about your water quality that you can access online. Failing that, arranging for a state-certified laboratory test is the best way to know exactly what’s in your water.

  • Jennifer Byrd
    Water Treatment Specialist

    For 20+ years, Jennifer has championed clean water. From navigating operations to leading sales, she's tackled diverse industry challenges. Now, at Redbird Water, she crafts personalized solutions for homes, businesses, and factories. A past Chamber President and industry advocate, Jennifer leverages her expertise in cutting-edge filtration and custom design to transform water concerns into crystal-clear solutions.

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