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Removing PFAS from public water will cost billions and take time – here are ways to filter out some harmful ‘forever chemicals’ at home

Kyle Doudrick, University of Notre Dame, The Conversation on

Published in Science & Technology News

There are more than 5,000 chemicals that are considered PFAS, yet only a few have been studied for their toxicity, and even fewer tested for in drinking water. The United States Geological Survey estimates that nearly half of all tap water is contaminated with PFAS.

Some money for testing and cleanup will come from the federal government. Other funds will come from 3M and DuPont, the leading makers of PFAS. 3M agreed in a settlement to pay between $10.5 billion to $12.5 billion to help reimburse public water systems for some of their PFAS testing and treatment. But public water systems will still bear additional costs, and those costs will be passed on to residents.

Another big question is how to dispose of the captured PFAS once they have been filtered out.

Landfills are being considered, but that just pushes the problem to the next generation. PFAS are known as “forever chemicals” for a reason – they are incredibly resilient and don’t break down naturally, so they are hard to destroy.

Studies have shown that PFAS can be broken down with energy-intensive technologies. But this comes with steep costs. Incinerators must reach over 1,800 degrees Fahrenheit (1,000 Celsius) to destroy PFAS, and the possibility of creating potentially harmful byproducts is not yet well understood. Other suggested techniques, such as supercritical water oxidation or plasma reactors, have the same drawbacks.

So who is responsible for managing PFAS waste? Ultimately the responsibility will likely fall on public drinking water systems, but the EPA has no waste regulations for PFAS.

Your first instinct might be to use bottled water to try to avoid PFAS exposures, but a recent study found that even bottled water can contain these chemicals. And bottled water is regulated by a different federal agency, the Food and Drug Administration, which has no standards for PFAS.

Your best option is to rely on the same technologies that treatment facilities will be using:

Activated carbon is similar to charcoal. Like a sponge, it will capture the PFAS, removing it from the water. This is the same technology in refrigerator filters and in some water pitcher filters, like Brita or PUR. Note that many refrigerator manufacture’s filters are not certified for PFAS, so don’t assume they will remove PFAS to safe levels.

 

Ion exchange resin is the same technology found in many home water softeners. Like activated carbon, it captures PFAS from the water, and you can find this technology in many pitcher filter products. If you opt for a whole house treatment system, which a plumber can attach where the water enters the house, ion exchange resin is probably the best choice. But it is expensive.

Reverse osmosis is a membrane technology that only allows water and select compounds to pass through the membrane, while PFAS are blocked. This is commonly installed at the kitchen sink and has been found to be very effective at removing most PFAS in water. It is not practical for whole house treatment, but it is likely to remove a lot of other contaminants as well.

If you have a private well instead of a public drinking water system, that doesn’t mean you’re safe from PFAS exposure. Wisconsin’s Department of Natural Resources estimates that 71% of shallow private wells in that state have some level of PFAS contamination. Using a certified laboratory to test well water for PFAS can run $300-$600 per sample, a cost barrier that will leave many private well owners in the dark.

For all the treatment options, make sure the device you choose is certified for PFAS by a reputable testing agency, and follow the recommended schedule for maintenance and filter replacement. Unfortunately, there is currently no safe way to dispose of the filters, so they go in the trash. No treatment option is perfect, and none is likely to remove all PFAS down to safe levels, but some treatment is better than none.

This article is republished from The Conversation, a nonprofit, independent news organization bringing you facts and trustworthy analysis to help you make sense of our complex world. It was written by: Kyle Doudrick, University of Notre Dame

Read more:
PFAS ‘forever chemicals’: Why EPA set federal drinking water limits for these health-harming contaminants

How to destroy a ‘forever chemical’ – scientists are discovering ways to eliminate PFAS, but this growing global health problem isn’t going away soon

PFAS ‘forever chemicals’ are getting into ocean ecosystems, where dolphins, fish and manatees dine – we traced their origins

Kyle Doudrick receives funding from the Department of Defense, the National Science Foundation, and the Semiconductor Research Corporation.


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