Does Reverse Osmosis Remove PFAS? Find Out the Truth

Yes, it does. 

According to the Nicholas School of Environment, Reverse Osmosis removes PFAS from water by 94% or more. 

It's totally normal to have second thoughts about getting a reverse osmosis (RO) system for your home. If your place is dealing with PFAS, it's definitely something to take seriously. 

But no worries! 

Reverse osmosis filters kick out almost all the contaminants, including those pesky 'Forever Chemicals,' PFAS. Just make sure to find a reliable store that sells well-made RO systems, and you’ll be all set.

Here are the 9 Best Reverse Osmosis Systems you can check. 

Understanding PFAS: The 'Forever Chemicals'

PFAS (per- and polyfluoroalkyl substances) are a group of human-made chemicals. This chemical has been around for various uses since the 1940s. 

[Source: PFAS source, persistence, and transport in the environment to humans, created with BioRender.com.]

They help make things waterproof, stain-resistant, and nonstick. That’s why you’ll find it in items like non-stick cookware, waterproof clothing, food packaging, and even firefighting foams.

However, PFAS has a strong bond with carbon-fluorine, which prevents it from degrading easily. As a result, PFAS starts to contaminate the air, water, and soil. You will be shocked to know that now, PFAS are found in the blood of humans and animals. 

PFAS are used in a wide array of industries:

• Aviation and Aerospace
• Automotive
• Biocides
• Building and Construction
• Chemical Industry
• Cosmetics
• Electronics
• Energy
• Explosives
• Medical Products

Health Risks of PFAS Exposure

The problem with PFAS is that they don’t break down easily. It can build up in our bodies over time. That is how the body starts to react to PFAS. 

[Source: A Critical Review and Meta-Analysis of Impacts of Per- and Polyfluorinated| frontiers]

When you come into contact with high levels of PFAS, you will suffer from: 

• PFAS in drinking water is thought to cause over 6,800 cancer cases every year.
• Some research has hinted at a potential connection to thyroid cancer.
• PFOA raises the chances of getting certain types of cancers in the liver, testicles, breasts, and pancreas.
• PFAS may affect how our liver functions.
• PFAS might lead to low birth weight, developmental delays, and immune system problems.
• Some PFAS can interfere with hormones.

Why Are PFAS Called ‘Forever Chemicals’?

PFAS have an incredibly strong chemical structure. They have earned the nickname “forever chemicals” because of their extreme durability in the environment. 

Other chemicals break down over time, but not with PFAS. Their bond with carbon-fluorine keeps them strong in organic chemistry. This makes them highly resistant to heat, water, and chemical reactions. 

• Once PFAS enter the environment, they remain intact for a long time.
• Traditional methods like boiling, filtering, or exposure to sunlight don’t easily degrade them.
• PFAS can seep into groundwater, rivers, and oceans, contaminating drinking water supplies
• PFAS don’t just stay in water and soil; they bioaccumulate in animals and humans.
• PFAS easily mixes with water and persists, allowing quick spread and large area coverage.

The Mechanism of Reverse Osmosis (RO)

Reverse Osmosis (RO) is one of the most effective ways to purify water. It cleans the water like it was never polluted. You can install RO at your home, office, or wherever needed. 

RO is an incredible process that helps remove harmful contaminants. 

But how does it actually work? 

How Does Reverse Osmosis (RO) Work?

At its core, reverse osmosis is a filtration process. It removes unwanted substances from water using a special semipermeable membrane. 

Here’s a step-by-step breakdown of what happens:

Step 01: Pressure Pushes Water Through the Membrane

• Semipermeable membranes are made from materials like cellulose acetate or polyamide resins.
• Water is forced through a semipermeable membrane under high pressure.
• Only pure water molecules can pass through this membrane.

Step 02: Contaminants Get Trapped

• The membrane acts like a super-fine sieve
• Block larger molecules like salts, bacteria, viruses, and chemicals
• Let clean water pass through

Step 03: Dirty Water is Flushed Away

• The contaminants that don’t make it through the membrane are flushed away as waste.
• Leave behind purified water on the other side

Step 04: Final Filtration and Storage

• Some RO systems have additional carbon or UV filters
• It removes any remaining taste, odor, or bacteria
• Lastly, the clean water is stored for use

Relatable Reads: Why Choose Reverse Osmosis (RO) for Your Drinking Water in New Jersey?

What Contaminants Does RO Remove?

RO is super effective at cleaning out all sorts of impurities. It can get rid of about 95-99% of dissolved salts, particles, organics, bacteria, and other stuff from the water. 

If a contaminant has a molecular weight over 200, a well-functioning RO system is likely to reject it. The RO will remove:

• Lead, arsenic, mercury, and chromium
• Removes per- and polyfluoroalkyl substances (PFAS)
• Excess salts to improve taste
• RO filters out chlorine and fluoride
• The membrane blocks most bacteria, parasites
• Remove traces of agricultural chemicals, industrial pollutants, and pharmaceuticals

Evaluating RO's Effectiveness Against PFAS

New Jersey residents are really worried about the PFAS level in their water. Not only the NJ residents but also PFAS in drinking water are big concerns for everyone. This is why people are turning to filtration technologies like Reverse Osmosis (RO). 

But how well does RO actually work against these stubborn “forever chemicals”? 

Let’s find out.

Research Findings: RO Can Remove Up to 99% of PFAS

• Reverse osmosis and two-stage filters did a great job of getting rid of almost all the PFAS chemicals that were tested.
• Reverse osmosis filters can get rid of about 94–99% of short-chain PFAS and 88–100% of long-chain PFAS.
• Studies from the U.S. Environmental Protection Agency (EPA) and other scientists show that reverse osmosis (RO) does a great job of getting rid of long-chain PFAS.
• A lot of home RO systems have been tested, and they really help bring down PFAS levels.

Factors Influencing RO’s Efficiency Against PFAS

While RO is powerful, its effectiveness can depend on:

Comparing RO with Other Filtration Methods

RO isn’t the only option for removing PFAS from water. Other filtration methods, such as Granular Activated Carbon (GAC) filters and Ion Exchange Resins, also exist. 

But how do they compare?

Granular Activated Carbon (GAC) Filters

GAC filters use highly porous carbon material to adsorb (trap) contaminants. You can use this in pitcher filters, faucet attachments, and whole-house systems.

PFAS Removal Efficiency:

• GAC filters can remove about 73% of PFAS on average.
• Their effectiveness depends on contact time and the type of PFAS present.
• Long-chain PFAS (like PFOA and PFOS) are removed more effectively

Limitations:

• The carbon gets saturated over time and stops trapping PFAS, requiring regular replacement.
• Short-chain PFAS may not be fully removed.
• Some GAC filters work great, while others are less effective depending on design and water flow rate.

Ion Exchange Resins

Ion exchange resins use charged resin beads that bind to PFAS molecules. They replace PFAS with safer ions like chloride. This method is commonly used in industrial water treatment plants. However, you can install it at home as well.

PFAS Removal Efficiency:

• Ion exchange resins can remove up to 90-99% of PFAS.
• They are especially effective at eliminating short-chain PFAS.

Limitations:

• High-quality ion exchange systems can be expensive for home use.
• The resin needs to be periodically replaced or regenerated, which may require professional service.
• Not Always Available for Homes

RO vs. GAC vs. Ion Exchange

Check out Reverse Osmosis vs Water Softener: Key Differences

Implementing RO Systems at Home

Since RO removes PFAS and other contaminants from your water, you should know about the whole system. Check for different system types, installation needs, and certifications.

Point-of-Use vs. Whole-House RO Systems

RO filtration can be installed at specific water sources (Point-of-Use). You can also install it in your entire home (Whole house). Each option has its pros and cons.

Point-of-Use (Under-Sink) RO Systems

What It Is: Installed under your kitchen sink to purify drinking and cooking water.
How It Works: Water from the cold-water line passes through an RO membrane, and clean water is dispensed through a dedicated faucet.
Best For: Homes wanting high-quality drinking water without filtering the entire house.

Whole-House RO Systems

• What It Is: Installed at the main water line to filter water for the entire house. You can also add it to the showers, laundry, and kitchen taps.
• How It Works: It treats all incoming water before it reaches faucets.
• Best For: Homes with serious water contamination concerns or well water issues.

Installation and Maintenance

Most under-sink RO systems come with installation kits and can be set up in a few hours. Here are some basic steps if you are thinking of doing it by yourself:

• Turn off the cold-water supply and attach a T-valve for the RO system.
• Mount the RO unit under the sink and connect it to the water supply.
• Install the RO faucet on the sink or countertop.
• Connect the drain line to dispose of wastewater properly.
• Flush the system before use to clear any residual particles.

For the maintenance, what you can follow is:

• Pre-Filters (Sediment & Carbon): Every 6–12 months (protects RO membrane from clogging).
• RO Membrane: Every 2–5 years (critical for PFAS removal).
• Post-Filter (Carbon): Every 12 months (improves taste and removes lingering contaminants)

Warning: If filters aren’t replaced on time, PFAS and other contaminants may pass through!

Certifications to Look For: Ensuring PFAS Removal

Certifications from trusted organizations to guarantee effective filtration.

• NSF/ANSI 53 & 58 Certification verifies the reduction of contaminants like PFAS, lead, and chlorine.  
• NSF/ANSI P473 certifies systems for PFAS removal.  
• WQA Gold Seal signifies high performance and safety standards.

Addressing Common Concerns

Reverse osmosis is great, but there are a few common issues that people talk about. Most of the concerns revolve around the wastewater it produces and how many minerals it removes.

Let’s talk about each concern. 

1. Waste Water Production

RO systems have this feature, which allows them to flush out the contaminated water down the drain. Other filtration does not do this “wastewater” thing. For example, a point-of-use RO system sends out five gallons of wastewater for every gallon of treated water. Therefore, some users do not appreciate the waste. 

What you can do is to reduce the wastewater:

• Invest in a thinner film composite (TFC) membrane. This can reduce wastewater by 10 to 15%. 
• Increase the inlet pressure to (50-80 psi). This will save 5-7% more water from becoming waste.

2. Mineral Removal

RO kills up to 92-99% of beneficial minerals in the water. These minerals are actually necessary for our bones and teeth. To deal with these issues, you can use several methods:

• Plugging remineralization cartridges directly into the RO membrane. It will add the mineral back into the water.
• Add mineral drops to RO water
• Use mineral stones in the water container 
• Add a pinch of Himalayan sea salt

Frequently Asked Questions

Can boiling water remove PFAS?

No, boiling water can not remove PFAS from it. You will need a proper filtration system to do so.

How often should RO system filters be replaced?

You can swap out the pre-filters every 6 to 12 months and the RO membrane every 2 to 5 years.

Are there any health risks associated with using RO-filtered water?

Generally, no. However, using RO for a long time may cause mineral deficiency for some people.