What are PFas?
PFAS (Per and Polyfluroalkyl substances) are a group of man-made chemicals that have been manufactured and used in a variety of industries since the 1940s. Some of the more common commercial applications have been for products like Teflon, stain & water–resistant materials, paints, polishes and fire fighting foams (a major source of ground water pollution near airports, military bases and fire fighting training centers). These chemicals are being detected at dangerous levels in drinking water supplies around the country. (For removal methods, see the lower section of this page).
PFOA and PFOS have been the most extensively produced and studied of these chemicals. Both chemicals do not break down and they can accumulate over time. There is evidence that exposure to PFAS can lead to adverse human health effects. As a result, these chemicals are no longer manufactured in the United States, but are still made in other countries and may be contained in products imported into the U.S. In May, 2016 the EPA issued a health advisory level at 70 parts per trillion for both PFOA and PFOS.
HEALTH AFFECTS OF PFAS
There is evidence that exposure to PFAS can lead to adverse health outcomes in humans. If humans or animals ingest it (by eating or drinking food or water), they are absorbed and can accumulate in the body. PFAS stay in the human body for long periods of time. As a result, as people get exposed from different sources over time, the level in their bodies may increase to the point where they suffer from adverse health effects.
Studies indicate that PFOA and PFOS can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals. Both chemicals have caused tumors in animal studies. The most consistent findings from human epidemiology studies are increased cholesterol levels among exposed populations, with more limited findings related to infant birth weights and:
- effects on the immune system
- cancer (for PFOA), and
- thyroid hormone disruption (for PFOS).
Note: see https://www.epa.gov/pfas/basic-information-pfas for more detailed information.
Removal of PFAs
Activated Carbon, Point of Entry System
There are technologies effective in removing PFAS from drinking water, especially Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS), which are the most studied of these chemicals. These technologies include activated carbon adsorption, ion exchange resins, and reverse osmosis. For activated carbon, make sure the system has been tested for the reduction of PFAS/ PFOA under NSF/ANSI 53 as well as P473 like the one in the above photo. https://h2ocare.com/carbon-filtration.
Reverse Osmosis, Point of Use System
This membrane based technology can be used in drinking water treatment facilities, in homes at the point-of-entry where water enters the home, or at a point-of-use such as at a kitchen sink. This will remove up to 99% or PFAS in the water. See http://reverse-osmosis-ro-water-purification.
Ion Exchange (Anion Resin)
This is a chemical-physical process that selectively removes contaminants from solution by effectively swapping out ions of similar electrical charges. In this way, Ion Exchange targets specific substances for removal based on their ionic charges, while leaving desirable or innocuous minerals in solution. Can be a trickier solution, depending on what other ions are in the water.