PFAs are a large group of man-made chemicals often called “forever chemicals” because they break down very slowly and can persist in water, soil, and the human body. PFOS and PFOA are two of the best-known PFAS. In drinking water, the biggest concern is long-term exposure, which is why testing and choosing the right treatment matter.
What are PFAs and Why Are They in My Water?
PFAS stands for per- and polyfluoroalkyl substances. These chemicals have been used in many industrial processes and consumer products because they resist heat, oil, stains, and water.
PFAS vs. PFOS vs. PFOAS
PFOS and PFOA are two legacy PFAS that have been studied extensively, but they are only part of a much larger PFAS family.
Common PFAS exposure sources
- Drinking water contaminated near industrial sites, landfills, airports, military sites, or wastewater-related sources
- Certain foods and food packaging
- Some stain-resistant, grease-resistant, or water-resistant consumer products
- Workplace exposure in certain industries
Role/expertise: Water filtration supplier and product specialists with experience in reverse osmosis, under-sink, whole-house, UV, water softener, well water, and commercial system selection
Last reviewed: May 19, 2026
Primary sources consulted: U.S. EPA, ATSDR/CDC, USGS, NSF, and peer-reviewed literature on PFAS occurrence and treatment
Signs PFAS May Be a Water Problem
PFAS usually do not create an obvious taste, smell, or color in drinking water. That means many homes with PFAS concerns will not notice visible warning signs at the tap. Testing is the best way to confirm whether PFAS are present.
Situations that may justify testing
- Your home is near an airport, military facility, landfill, industrial site, or known contamination area.
- Your utility has issued a PFAS notice or public update.
- Your private well is near a possible source area.
- You want to investigate a long-term water-quality concern even though the water looks normal.
Why Do PFAS Matter?
Scientific studies suggest that exposure to some PFAS may be associated with harmful health effects. ATSDR and CDC materials describe potential associations that may include increased cholesterol levels, reduced antibody response to some vaccines, changes in liver enzymes, small decreases in birth weight, pregnancy-related complications such as preeclampsia, and kidney or testicular cancer for certain PFAS. Research on forever chemicals is ongoing, and risk depends on factors such as the specific PFAS, exposure level, and duration of exposure.
Possible health concerns linked to some PFAS
- Increased cholesterol levels
- Lower antibody response to some vaccines
- Changes in liver enzymes
- Small decreases in birth weight
- Pregnancy-induced hypertension or preeclampsia
- Kidney cancer and testicular cancer for certain PFAS
Home and Plumbing Impacts
PFAS are mainly a concern for drinking water exposure, not a scale or staining issue like iron or hard water. In most homes, the practical concern is ingestion through:
- Drinking tap water
- Making coffee, tea, and ice
- Cooking
- Mixing infant formula
- Brushing teeth
Because ingestion is the main concern, many homeowners focus first on treating the water they drink and cook with.
How to Test for Per- and Polyfluoroalkyl Substances (Forever Chemicals)
For public water users
Start by checking your local utility’s water-quality information and any PFAS notices or compliance updates. If you want household-specific confirmation, use a certified drinking-water lab that offers PFAS testing.
For private well owners
Private well owners usually need to arrange their own testing through a qualified lab. This is especially important if the property is near a potential PFAS source or if local agencies have raised concerns about groundwater contamination of forever chemicals.
Testing tips
- Ask the lab which PFAS compounds are included in the panel.
- Follow sample-handling instructions carefully.
- Avoid contamination during sampling.
- Keep the report for comparison after treatment is installed.
- Retest after installation to verify performance when needed.
Best Treatment Options for PFAS
Note: No water filtration system or other technology has proven to destroy PFAS, but they can help reduce them. Be cautious about any product that claims to completely remove PFAS from drinking water.
No single solution is right for every situation, but the most commonly referenced PFAS reduction technologies for drinking water are:
Reverse osmosis
Reverse osmosis is often one of the strongest point-of-use options for PFAS reduction in drinking water. Peer-reviewed reviews and exposure-reduction guidance note that RO systems have shown strong performance for many PFAS.
Granular activated carbon
Granular activated carbon can reduce PFAS, but performance can vary based on the specific PFAS, water chemistry, bed size, contact time, and maintenance. It is generally more reliable when the product is specifically designed and certified for PFAS reduction rather than when it is chosen as a generic carbon filter.
Anion exchange resin
An anion exchange resin filter is another recognized PFAS treatment technology and is often used in larger or more specialized treatment setups.
Whole house vs. Under-Sink vs. RO vs. UV
Under-sink PFAS treatment
An under-sink system is often the most practical starting point when the goal is to reduce PFAS in the water you drink and cook with. It focuses treatment at one tap and can be a cost-effective way to address ingestion exposure.
Reverse osmosis systems
Reverse osmosis is usually the strongest fit when PFAS reduction is the priority for drinking and cooking water. This is often the best option for people who want a point-of-use drinking-water solution rather than treating every tap in the home.
Whole house systems
A whole house approach may make sense when you want broader treatment for the entire home, but whole house PFAS strategy should be planned carefully and tied to certified performance and expected flow demand. Activated carbon is one of the treatment technologies commonly discussed for PFAS reduction, but product-specific certification and sizing matter.
UV systems
UV systems are not a PFAS removal technology. UV is used for microbiological treatment, such as controlling bacteria or viruses, not for removing PFAS from water.
Which Water Filtration Solutions May Fit PFAS Concerns?
Related solutions sold by H2O Distributors include:
- Reverse osmosis systems for drinking and cooking water
- Under-sink filtration systems for point-of-use treatment
- Whole house carbon systems for broader home treatment goals
- Replacement cartridges and components for ongoing maintenance
Practical PFAS Buying Guidance
When comparing treatment options, focus on:
- whether the goal is drinking-water treatment or whole-home treatment
- whether the product has a PFAS reduction claim or certification
- the specific PFAS listed in test data or certification materials
- maintenance requirements and replacement schedule
- flow rate and capacity
- whether post-installation testing is planned
Reverse Osmosis Water Filters Under Sink Water Filters Countertop Water Filters Whole House Water Filters Everpure Systems and Cartridges Carbon Block Cartridges Granular Activated Carbon Cartridges Aries Filter Works Specialty Cartridges
From NSF.org
NSF/ANSI Standard 53: Drinking Water Treatment Units – Health Effects
Overview: Standard 53 addresses point-of-use (POU) and point-of-entry (POE) systems designed to reduce specific health-related contaminants, such as Cryptosporidium, Giardia, lead, volatile organic chemicals (VOCs), MTBE (methyl tertiary-butyl ether), that may be present in public or private drinking water.
NSF/ANSI Standard 58: Reverse Osmosis Drinking Water Treatment Systems
Overview: This standard was developed for point-of-use (POU) reverse osmosis (RO) treatment systems. These systems typically consist of a pre-filter, RO membrane, and post-filter. Standard 58 includes contaminant reduction claims commonly treated using RO, including fluoride, hexavalent and trivalent chromium, total dissolved solids, nitrates, etc. that may be present in public or private drinking water.
Frequently Asked Questions About Forever Chemicals
Q: What are PFAS in water?
A: PFAS are a group of long-lasting man-made chemicals that can persist in drinking water and may build up over time. PFOS and PFOA are two of the best-known examples.
Q: Can you see or taste PFAS in drinking water?
A: Usually no. PFAS often have no obvious taste, smell, or visible sign, which is why testing matters.
Q: What is the best water filter for PFAS?
A: Reverse osmosis is often one of the strongest point-of-use options. Activated carbon and anion exchange can also reduce PFAS, but product-specific performance and certification matter.
Q: Does UV remove PFAS?
A: No. UV is used for microbiological treatment, not PFAS removal.
Q: Should I choose whole house or under-sink treatment for PFAS?
A: Under-sink or RO treatment is often the most practical choice when the main concern is drinking and cooking water. Whole house treatment can make sense in some cases, but it needs careful sizing and product-specific PFAS performance review.
Q: How do I know if my home should test for PFAS?
A: Testing makes the most sense when you use a private well, live near a possible PFAS source, or want confirmation after a utility notice or local contamination concern.
Concerned about PFAS in your water? Start with the right test, then choose a treatment solution built for your drinking-water goals and backed by clear performance data.
A boil-water advisory or boil-water order is a public health advisory or directive given by government or health authorities to consumers when a community’s drinking water is, or could be, contaminated by pathogens.
Learn how to make an emergency water filter for disaster situations out of some common items.
This method does work and can keep you heathly if clean potable water or a manufactured water filter system are unobtainable.
The Hydrologic Cycle (also called the Water Cycle) is the continuous movement of water in the air, on the surface of and below the Earth.
This cycle is the exchange of energy which influences climate. When water condenses, it releases energy and warms the environment.
90% of the garbage floating in the Earth’s oceans is plastic and less than 5% of all plastic is recycled.
The patch mostly consists of pelagic plastics, formed from plastic bags, plastic water bottles, bottle caps and styrofoam.
Hydraulic fracturing (sometimes referred to as fracking or hydrofracking) is a relatively new form of natural gas extraction.
The fluids used in the fracking process flow back to the surface, often entering the water table or polluting the drilling area, and sometimes improper disposal of waste water from the wells.
As our technology advances, so do new forms of pollution and contaminants that effect our environment and our health.
Read more about drinking water contaminants and their health effects.
Chlorine has long been recognized as an oxidative agent, meaning that it not only kills the germs in the water supply; it will damage any living tissue with which it comes in contact. And your skin, like the rest of your organs, is living tissue. But that’s not the only problem.
Since the discovery of its health benefits in the mid-1940’s, fluoride is often added to the public water supplies of industrialized countries in order to reduce the populations tooth decay, which is especially effective in low income communities, where good dental hygiene may be too costly.
Chromium-6 was found in the drinking water supply of the southern California town of Hinkley and brought to national attention by Erin Brockovich.
The EPA is reviewing effects of Chromium-6 after a recent report brought to light dangerous levels in a number of major US cities.
Giardia is a flagellated protozoan parasite that colonizes and reproduces in the small intestines of humans and other animals, which can cause giardiasis.
Symptoms of Giardiasis usually show after 3 to 4 days, and include gastrointestinal and constitutional problems.
Cryptosporidiosis is a disease caused by the parasite Cryptosporidium parvum.
Since a outbreak in 1993 in Wisconson, new attention has been focused on determining and reducing the risk for Cryptosporidiosis from community and municipal water supplies.
What is reverse osmosis? What is a 4-Stage system? What are the components in a system? Visit our ‘How Reverse Osmosis Works‘ guide to find the answers.
Also see out list of contaminants RO removes and comparison chart for particle sizes to learn more about reverse osmosis.
What is ultraviolet light? Do I need to filter the water before the UV process? How exactly can light kill organisms?
Visit our ‘How Ultraviolet Purification Works‘ guide to find out how it works.
The typical water softener is a mechanical appliance that’s plumbed into your home’s water supply system. All water softeners use the same operating principle: They trade the minerals for something else, in most cases sodium. The process is called ion exchange. More…
Step by step instructions on installing replacement cartridges and sanitizing filter housings. It is highly recommended that you clean and sanitize your system once a year.
Need help installing your new RO system, how to perform maintenance, or how often to change your cartridges?
View our printable Reverse Osmosis Installation Guide to learn more.
Step by step instructions on making a connection with Quick-Connect fittings. Quick-connect fittings allow you to connect and disconnect tubing without the need of tools. For larger, plumbing size fittings read our using twist lock guide.
Step by step instructions on making a connection with Twist and Lock fittings. Twist-Lock fittings allow you to connect and disconnect tubing without the need of tools.
Step by step instructions on making a connection with SharkBite Push-To-Connect fittings. SharkBite fittings allow you to connect and disconnect pipes without the need of using PVC glue or welding copper.
Need to filter water but not sure about the differences between or applications of our systems?
Use our Water Filter Systems Guide to find out which system is best for your filtration needs.
Need to replace your system’s cartridges but not sure what type is best for your system?
View our Cartridge Replacement Guide or contact us to find out what you need.
View a chart comparing the specifications of all the reverse osmosis systems we sell on this site. All bladder tanks are NSF certified.
The size of your water softener depeneds on the total grain per day that need to be removed.
This is determined by the number of people in your household, grain per gallon (GPG) hardness and the amount of Iron present in the water.
A micron is a unit of measurement for how small of particles a filter will catch. The lower the micron size, the tinier the ‘holes’ in the filter cartridge are that allows water to pass through, ranging from 0.1 absolute to 150 microns.
Use our Pore Size Efficiency Guide to find out what micron size to use.
Pleated sediment cartridges remove dirt, rust and sediment from water while providing an increased surface area and longer life. Pleated filters down to 5 microns are washable and reusable.
Use our Pleated Sediment Cartridge Comparison to find the filter cartridge you need.
Aquariums need three types of filtration to maintain a healthy environment for freshwater, saltwater or amphibian aquariums (sediment filtration, carbon filtration, and removal of biological contaminants).
When traveling around the state or the country in a RV you might not always know where you will be getting the water from or what might be in it. Water that is stored in a RV holding tank will not stay potable for long and can become a breeding ground for algae and bacteria.
Chemicals added to public water supplies, like chlorine, can be harmful to the living cells of plants.
When brewing beer with tap or bottled water, chlorine and chloramine present in the water can combine with malt phenols in the wort to create a compound called chlorophenol, which can give the beer a medicinal taste.
View our Filtered Water for Home Beer Brewing guide.
Bottled water requires a lot of resources to manufacture and ship, and costs a lot more than reverse osmosis water.
Use our Bottled Water Cost Calculator to find out how much of an impact you have on the environment.
