Toxic 'Forever Chemicals' in Water : What is PFAS in Drinking Water?

Toxic 'Forever Chemicals' in Water : What is PFAS in Drinking Water?
PFCs, PFAS, PFOA, and PFOS are abbreviations for different but related contaminants that threaten the environment and well-being of people and wildlife. As of January 2021, over 2,300 places in America (49 states!) are known to have PFAS contamination. In fact, PFAS is likely detectable in all major water supplies in America and especially those that use surface water.

Perfluorinated chemicals (PFCs)

Perfluorinated chemicals (PFCs) are a group of toxic chemicals most famous for their use in making Teflon non-stick pans. Created in a laboratory accident in 1938 and refined over the following years, Teflon is considered a "miracle chemical" due to its superior nonstick properties. However, perfluorinated chemicals have a toxic legacy.

Polyfluoroalkyl and Perfluoroalkyl Substances (PFAS)

PFAS - poly- and perfluoroalkyl substances - were previously referred to as PFCs. Although there are almost 5,000 chemicals in the PFAS family, they all have a couple things in common: they're man-made chemicals and have a carbon and fluorine atom backbone. PFAS contamination is widespread; people and wildlife around the world have been exposed to it, even in the most remote reaches of this planet. These toxic substances have been found in rivers, lakes, groundwater, public water systems, soil, air, and in many types of animals on land and in the water. Disturbingly, 99.7 percent of Americans have PFAS in their blood! Since sunlight, microbes, and heat won't break them down - they're virtually indestructible - scientists call them "forever chemicals" due to their persistence in the environment and our bodies. These chemicals are still being introduced into environment and can persist for a very long time. Manufacturers use PFAS to make products and coatings that resist heat, oil, stains, grease, and water. For example, stain-resistant fabrics and carpets, water-repellent clothing, nonstick cookware, fast food packaging (i.e., pizza boxes), firefighting foam, and hundreds of other consumer products.

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS)

Perfluorooctanoic acid (PFOA) - known colloquially as C8 - and perfluorooctane sulfonate (PFOS) are the most widely studied PFAS chemicals. The largest producers of PFOA and PFOS in America - 3M and Dupont - have discontinued producing these chemicals, however very close variations of them are still being produced under different names. For example, in 2015 Dupont created spin-off company called Chemours which manufactures GenX, an alternative to PFOA. Chemours is one of largest producers of fluorochemicals in the world.

What is the Limit for PFAS in Drinking Water?

Independent scientific studies have recommended a PFAS limit of 1 part per trillion (PPT) in drinking water. For water, the EPA provides a health advisory of no more than 70 PPT for PFOA and PFOS combined. To put 70 PPT in perspective, that's roughly 70 droplets in an Olympic-sized pool. This is only a "guideline" though and not enforceable. 70 PPT is a tiny, tiny amount but our cells do respond to such chemicals at a part-per-trillion concentration. Federal limits don’t always mean safe. As Environmental Working Group (EWG) explains:
Legal limits are based on economic and political considerations that usually don’t reflect the lower levels that scientists have found pose health risks. Indeed, over 85 percent of the cancer risk calculated in the EWG study is due to contaminants that were below legal limits. Legal limits may also be based on outdated science: No new contaminants have been added to the list of nationally regulated drinking water pollutants in two decades. – Environmental Working Group, 2019

Why is PFAS a problem in our water?

Hundreds of millions of Americans could have PFAS-contaminated drinking water. PFAS in water are a huge concern because exposure can cause significant, adverse health effects. One study has linked PFOA exposure with high cholesterol, ulcerative colitis, thyroid disease, pregnancy-induced hypertension, and testicular and kidney cancers. Corporations that have knowingly and unknowingly introduced these chemicals to the environment have done little financially or otherwise to fix the problem, leaving utilities and drinking water suppliers with the responsibility and bill, and people with the lasting health effects. As one scientist points out, water filters are really only a temporary solution to the issue and “the real goal should be control of PFAS contaminants at their source.” (Detlef Knappe, 2020). The Devil We Know (BBC Four, 2018) is a blood-boiling documentary about a West Virginia community that confronts DuPont after they discover it has knowingly been dumping toxic chemicals into the local drinking water supply. Dark Waters (2019 Film), starring Mark Ruffalo and Anne Hathaway, is a dramatized take on Robert Bilott's case against DuPont after they hazardously dumped PFOA and PFOS. Both movies are unsettling and well-worth watching to understand the scope of this issue and why PFAS is a problem in water.

PFAS in Water Health Effects

Exposure to PFAS in water can cause significant, adverse health hazards including but not limited to:
  • High cholesterol
  • Ulcerative colitis
  • Thyroid disease
  • Pregnancy-induced hypertension / preeclampsia
  • Cancer - testicular, kidney
  • Developmental effects to fetuses during pregnancy
  • Immune effects
  • Thyroid effects

Do water filters remove PFAS?

Not all water filters completely remove toxic polyfluoroalkyl and perfluoroalkyl substances (PFAS). In fact, only certain water filtration technologies remove or reduce them. Reverse osmosis (RO) and activated carbon filtration, and anion exchange treatment are the most effective for PFAS, PFOA / C8 (perfluorooctanoic acid), PFOS (perfluorooctane sulfonate), and PFCs (perfluorinated chemicals). Among these technologies, not all systems are created equal or necessarily remove all PFAS either though. Keep in mind that the effectiveness of any filter in removing and reducing PFAS depends on the concentration of PFAS in the incoming water, how old the water filter is, size of the filter, flow rate, inlet line pressure, and local water conditions.

Does reverse osmosis remove PFAS?

Yes, reverse osmosis is extremely effective at removing PFAS. Research by Duke and NC State scientists found that RO systems were over 90 percent effective at removing a wide range of PFAS. They tested for three perfluoroalkal sulfonic acids (PFSAs), seven perfluoroalkyl carboxylic acids (PFCAs) and six per- and poly-fluoroalkyl ether acids (PFEAs) including GenX. Reverse osmosis had a near perfect removal of these PFAS.

What's the Best Water Filter for Removing Toxic PFAS?

Our top picks for removing and reducing toxic PFAS from drinking water Best whole house water filters for removing and reducing toxic PFAS
  • PS-2000PB - 0.02 Micron Ultrafiltration Membrane System with 0.5 micron activated carbon filter for lead / chemicals / heavy metals
  • BG-20PB - 0.5 micron activated carbon filter for lead / chemicals / heavy metals
For drinking water, a high quality, properly maintained reverse osmosis system provides the best protection against PFAS due to the high-pressure membrane which separates and removes virtually everything from the water. In a research study by Duke and NC State scientists in 2020, the under-sink reverse osmosis systems they tested achieved near-complete removal of the PFAS chemicals they tested. Other high-pressure membrane systems including nanofiltration and ultrafiltration are effective at removing and reducing PFAS. Reverse osmosis membranes are the tightest (pore size is approximately 0.0001 micron), followed by nanofiltration (pore size is approximately 0.001 micron), and ultrafiltration (pore size is approximately 0.01 micron). When these membrane systems include activated carbon filter(s) they are even more effective! Certain activated carbon filters effectively remove and reduce PFAS. Make sure the activated carbon filter is suited for PFAS reduction because some carbon filters - especially Brita and Pur pitcher filters - are NOT designed to remove or reduce PFAS in your tap water. As with any filter, its effectiveness depends on the concentration of contaminants in the incoming water, filter age, filter size, flow rate, inlet line pressure, and local water conditions. Be sure to replace your filters regularly too - this is key to effectiveness!

Reverse Osmosis and PFAS

A high quality, properly maintained reverse osmosis system is the most effective technology in removing the largest number of contaminants including PFAS. An adequate RO system consists of a sediment filter (5 micron or less), carbon filters (5 micron or less), and an RO membrane. Reverse osmosis is intended for drinking water (point-of-use basis), and not a viable option to treat all of the water used in your home unfortunately. Reverse osmosis is not recommended for whole house filtration because it typically "wastes" three or more gallons of water per one gallon of RO water produced, and would require an extensive tank since water is not produced on demand (tanks are prone to bacteria growth which is also an issue). We recommend the HydroGuard reverse osmosis system for removing and reducing PFAS.

Activated Carbon Treatment and PFAS

Some activated carbon filter systems remove or reduce certain PFAS concentrations in drinking water. There are many types and sizes of carbon filters, however most are designed for taste and odor issues rather than for PFAS. So which activated carbon filters remove and reduce PFAS? High quality, low micron activated carbon block filters (best choice) and high quality, low micron granular activated carbon filters (GAC). Activated carbon block filters are more effective than GAC filters because carbon block filters have a much larger surface area. The larger surface area means greater capabilities in filtering out particles, heavy metals, and contaminants, and they can filter more water. In the Duke and NC State study, the activated carbon filters they tested removed 73% of PFAS contaminants on average. It's important to note that some filters removed PFAS completely, whereas some did not reduce any at all. Thus 73% is just an average for the filters they tested - not a universal percentage across all activated carbon filters. We recommend the BG-20PB or PS-2000PB. The 0.5 micron activated carbon block filter contained in these systems removes and reduces lead, heavy metals, and chemicals including PFAS.

Ultrafiltration and PFAS

Ultrafiltration membrane filtration removes particles on a microscopic level and combined with an activated carbon block filter, it will remove and reduce PFAS. Although an ultrafiltration membrane is not as fine as reverse osmosis (it filters to approx 0.01 micron), it can provide benefits over RO while still providing protection from PFAS. Plus, pairing it with an activated carbon block cartridge or two, it We recommend the PS-PURUF for drinking water and the PS-2000PB for whole house water filtration.

Anion exchange treatment and PFAS

In an ion exchange treatment, undesirable ionic contaminants including PFAS (negative charge) are attracted to an anion exchange resins (AER; positive charge), removing them from water. This type of water treatment is not as readily available as the other types of treatment for PFAS.

How do I get rid of PFAS?

Avoid purchasing or, at a minimum, limit use of products containing PFCs. PFAS are biopersistent. This means that once PFAS are in the body, they stay there for a long time rather than being completely broken down or expelled quickly. Polyfluoroalkyl and perfluoroalkyl substances bioaccumulate (accumulate over time.) Additionally, PFAS biomagnify; when you ingest other plants or animals that have been exposed to PFAS, PFAS are transferred to you. This means that eating fish that has been exposed to PFAS means PFAS can be passed to your body. These are just a few reasons why these chemicals are problematic for the environment and human health. The CDC measures several types of blood PFAS in the US population. Certain PFAS may go down in blood levels of a population if their use declines. For example, PFOS and PFOA production and use has declined since 2002. In the CDC's National Health and Nutrition Examination Survey (NHANES) they discovered that between 1999 to 2014, blood PFOS levels declined by more than 80% and blood PFOA levels declined by more than 60%.  Additionally, during the same time frame blood PFAS and PFHxS blood levels went down in long-term residents after a water filtration system was installed. Keep in mind that as PFOS and PFOA are phased out and replaced, people may be exposed to other PFAS.

Does tap water have PFAS?

It's very scary but yes, your tap water may have PFAS. As of January 2021, over 2,300 places in America (49 states!) are known to have PFAS contamination. In fact, PFAS is likely detectable in all major water supplies in America and especially those that use surface water. To know for sure if your tap water has PFAS you will need to test for it, as not all municipal tests for PFAS and report it.

How do I remove PFAS from water at home?

A suitable water filtration system will remove or reduce PFAS from your water. High-pressure membranes (reverse osmosis, nanofiltration, ultrafiltration), activated carbon filtration, and ion exchange treatment are the most effective at removing PFAS from water. Common water pitcher brands like Brita and Pur are NOT designed to remove or reduce PFAS in your tap water. Fridge water filters It's unlikely that  Keep in mind that the effectiveness of any filter in removing and reducing PFAS depends on the concentration of PFAS in the incoming water, how old the water filter is, size of the filter, flow rate, inlet line pressure, and local water conditions. We recommend the HydroGuard reverse osmosis system for removing and reducing PFAS.

Does Boiling Water Remove PFAS?

No! If your water contains PFOA, PFOS, or other PFAS do NOT boil your water. Boiling it will actually concentrate the toxic chemicals posing even greater health risk. Heat doesn't break down PFAS.

What to do if there is a PFOA, PFOS, or other PFAS water advisory: 

Please follow advice from your local water authority during the advisory. If you have a water treatment system that removes and reduces PFAS then you should not be alarmed, however, make sure you're using this filtered water for all drinking, cooking, bathing, brushing your teeth, dish washing, giving to pets, and other activities that may result in ingestion.

How long do PFAS stay in your system?

PFAS stay in your body for a long time. This is because PFAS are biopersistent - they don't break down or get expelled from your body quickly. Depending on the level of exposure, they may stay in your blood levels for your entire life.