PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate) are highly toxic synthetic chemicals commonly used to manufacture teflon cookware, carpet, clothing, pizza boxes and airport fire-fighting chemicals. They can enter the water supply from chemical dumping, water run-off, landfills and air fields. Contamination is usually located near a source of the chemicals and can affect private wells and municipal water supplies. The strong Carbon-Fluorine bond in PFAS compounds make them very resistant to microbial degradation. Most of the US population has been exposed to one or more of these chemicals.
Health Effects of PFOA and PFOS: PFOA and PFOS could also be dangerous to pregnant women. Some studies indicate development problems and low birth weight. Other health issues include high cholesterol, thyroid cancer, testicular cancer, ulcerative colitis and kidney cancer. USEPA Health Advisory level for PFAS as of 2016 is 70 parts per trillion (PPT).
How to Remove PFOA and PFOS: In water, PFOA and PFOS are anionic substances. Ion exchange resins and granular activated carbon have found to be effective in treating these compounds. Air stripping, air sparging are found to be ineffective for PFOA and PFOS due to their low volatility and resistance to microbial degradation. Chemical oxidation is slow or not effective due to the strong C-F bond. Chemical reduction has shown some promise and is an area of active research.
In most cases a whole-house activated carbon filter is the Best Available Technology (BAT) for treatment of these chemicals. Another option is a WECO reverse osmosis filtration system with carbon block and granular activated carbon pre-filtration stages and granular activated carbon post filtration. Complete 5-stage water purification system removes tastes and odors along with suspended particles like sand and grit, chlorine, chloramine, carcinogenic chemicals, pesticides, solvents, and heavy metals like lead, cadmium, copper and arsenic. WECO whole-house and commercial filtration systems are also available.