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What are PFAS and why are they in the news? PFAS in drinking water pose serious long term health problems. Yet they are just now being discovered in water systems throughout the US. PFAS are just one of a group of chemical compounds causing grave health concerns. Low exposure to some PFAS chemicals has been linked to cancer, thyroid issues, and weakening childhood immunity.

Various forms of PFAs are present in rain throughout the planet which means they are now in everyone's drinking water.

"Per- and polyfluoroalkyl substances (PFAS) are a group of man-made chemicals that includes PFOA, PFOS and GenX chemicals. Since the 1940s, PFAS have been manufactured and used in a variety of industries around the globe, including in the United States." – USEPA

There are over 9000 different variations of PFA compounds. And, it turns out that EPA has been using a test to identify their presence that only identifies about 30 of those. So PFAs are much more prevalent than anyone, even the regulators, had imaginged. Sampling in a number of communities have shown widespread contamination that was previously unknown.

PFAs are common in water throughout the United States

Read this EPA document for a detailed description of these chemicals and they’re health effects. Here’s an excerpt from the following article: “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 animals.”


PFAs and their numerous sister compounds are common and have now been found in rain throughout the entire globe. This news comes after the discovery that USEPA had been using the wrong means to measure them. You can now assume the are in your water. A review  ofyour local water report can let you know if your utility has tested for them. Here's some basic information about PFAs from EPA:

The following map shows areas in the US with known PFA contamination. Actually the situation is much worse than the map below illustrates. For a more recent interactive map that you can zoom in to your location visit here

PFA Contamination in the United States


Recently CNN posted the following articles on PFAS in numerous cities in southern California. Because of the long term health effects this is an issue to take seriously. Therefore learn what you can to remove them from the water entering your home.  But first check, if you live in California, out these two links.

CNN article on PFAs in California drinking water:

The problem with PFA contamination of drinking water is national

As the map above illustrates cities around the country have PFAS in drinking water. Therefore, the action to take wherever you live is to check your local water quality report. This report is provided every year by your water supplier. It lists the regulated contaminants in your water. These reports are beginning to address the issue of PFAS and their associated compounds. You can often find these reports online. Learn how to find your water report here.

Previously unknown PFAs have been discovered in the Cape Fear River in North Carolina. The freaky thing about this is that USEPA was not aware of the compounds. You can read more here.

Removing PFAS from Drinking Water

If you live in a location where these contaminants are in your drinking water take action now. Whole house filters like my Urban Defender will reduce the level of PFAS in water dramatically. So will a good carbon based kitchen filter like my Kitchen Defender. A reverse osmosis system at the kitchen sink can eliminate them. Thus preventing you from ingesting them.   

Reducing PFAS in Drinking Water with Treatment Technologies | US EPA

Recently a well known national environmental group made claims about countertop filters removing PFAs. They performed a test on a number of new filters and found varying percentages of removal. What this tells me is that carbon can remove PFAs. But I never recommend countertop filters - why? Because they don't have enough carbon to remain effective for more than a few minutes...or weeks anyway. And in my 20 + years of experience even my best customers are bad at remembering to change filters. Just forget about countertop systems. If I thought they were good I would sell them ... and I don't. You need a water filter that has enough media in it (carbon in this case) to capture the contaminants.


Take these steps:

1) Look at the map above - these are the locations where the PFA issue is quite serious. However, PFAs are now present in rainfall. Therefore they are in everyone's water.

2) Contact your water provider and ask for a water quality report or search for it online. You may contact me to interpret and discuss your water report during working hours.

3) If they PFAs or PFOAs are present take immediate steps to stop drinking them. Purchase water treated with reverse osmosis from your local supermarket until you can install Sweetwater's custom reverse osmosis systems.

NOTE: As of mid August 2022 a team of scientists has discovered a way to cause PFAs and related compounds to breakdown. This, as luck would have it, is a relatively easy chemical procedure. While not yet available or fully developed it will no doubt be installed at water treatment plants in the coming years. 


When in doubt call me for help


JimMcMahon 2022 3474

James P McMahon, ecologist


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