The most researched method of PFAS elimination is treatment with activated carbon. In drinking water treatment systems, activated carbon is frequently used to adsorb synthetic organic pollutants, natural organic compounds, and taste and odor molecules.
The huge family of thousands of synthetic chemicals known as per- and poly-fluoroalkyl substances (PFAS) is utilized extensively in society and is found in the environment. All PFAS linger in the environment for a very long time compared to other artificial compounds.
It is known that some PFAS can build up in people and other species and have harmful effects. Activated carbon-filled mobile adsorbers are used to remove PFAS from drinking water and groundwater. Because PFAS linger in the environment forever and build up in the body, some scientists refer to them as “forever chemicals.” According to Stapleton, they are now almost always present in tests of human blood serum.
Environmental Science & Technology Letters, a peer-reviewed journal, published the researchers’ results on February 5. It is the first study to look at point-of-use filters’ abilities to remove PFAS in a residential setting.
In Chatham, Orange, Durham, and Wake counties in the center of North Carolina, as well as New Hanover and Brunswick counties in the southeast, they examined filtered water samples taken from residences. Three perfluoroalkal sulfonic acids (PFSAs), seven perfluoroalkyl carboxylic acids (PFCAs), and six per- and poly-fluoroalkyl ether acids were among the PFAS pollutants that were evaluated in the samples (PFEAs).
One of the PFEAs they tested for was GenX, which has been discovered at significant concentrations in water in the Wilmington region of southeast North Carolina.
Important lessons include:
- Although the small number of two-stage filters examined makes it necessary for additional testing to discover why they performed so well, reverse osmosis filters and two-stage filters reduced PFAS levels, especially GenX, in water by 94% or more.
On average, PFAS pollutants were removed by activated-carbon filters at a rate of 73%, but results varied substantially.
- Chemicals were partially or totally eliminated in some instances while they were completely decreased in others. Researchers found no discernible correlations between filter brand, age, or source water chemical levels and removal effectiveness. However, researchers stated it is probably a very good idea to replace filters frequently.
- The effectiveness of whole-house systems using activated carbon filters to remove PFAS varied greatly. After filtration, PFSA and PFCA levels actually rose in four out of the six systems that were put to the test.
The systems can also expose house pipes to bacterial growth since they eliminate disinfectants used in city water treatment.
You can take action to lessen your possible exposure to PFAS if you are concerned about your health. PFAS can be effectively removed from water supplies using filters using reverse osmosis membranes or activated carbon.
To function properly, all water treatment systems need routine maintenance. Unmaintained water treatment systems will gradually lose their effectiveness.
ALSO SEE: Does a Carbon Filter Remove PFAS?
PFAS are unlikely to be eliminated by other types of typical water treatment systems, such as water softeners or iron filtration systems. PFAS cannot be removed by boiling water. Despite the fact that many households have whole-house iron or water filtration systems, sample data show that these systems DO NOT eliminate PFAS.
To minimize PFAS in drinking water, there are point-of-use (water is treated at a single faucet or site) and point-of-entry (all water in your home is treated) treatment solutions. In general, point-of-use therapy is less expensive than point-of-entry. When the device is installed and maintained correctly, the following treatment solutions are efficient in removing PFAS from drinking water.
Water is pushed through a membrane with microscopic pores using electricity in reverse osmosis. Water can travel through the membrane while it blocks numerous pollutants. A more feasible point-of-use treatment option is reverse osmosis (not at point-of-entry).
Filter with granular activated carbon: As water flows through the filter, contaminants build up on it.
Evaluation of Perfluorochemical Removal by a Small, In-Home Filter, a point-of-use carbon filter solution for drinking water filtration at a sink faucet, was tested by MPCA, MDH, and West Central Environmental Consulting (PDF).
Find out more about using carbon filters to treat water: GAC Filter Details.
Some ion exchange resin systems have the potential to remove PFAS, however, it’s important to check that the system you choose complies with the NSF/ANSI certification standards stated below.
To combat PFAS, search for products certified to NSF/ANSI 53 (for filters) or NSF/ANSI 58 (for other water treatment) (reverse osmosis).
Visit the Home Water Treatment homepage to learn more about these treatment alternatives, their advantages and disadvantages, and general pricing. You can choose the best alternative for your household with the assistance of a water treatment expert.
Although homeowners may install equipment in homes they own and inhabit, water treatment systems in Minnesota must be installed by a certified and bonded plumbing or water conditioning professional. After installation, it is crucial to maintain the treatment system according to the manufacturer’s instructions.