A New Chemical Process Successfully Destroys Toxic PFAS Forever Chemicals

For decades, scientists have struggled to find a way to eliminate polyfluoroalkyl substances, commonly known as PFAS. These toxic “forever chemicals” build up in our environment and our bodies. Now, a team of chemists has developed a low-temperature method that easily breaks down these once-indestructible molecules into harmless byproducts.

What Are PFAS and Why Are They So Hard to Destroy?

Polyfluoroalkyl and perfluoroalkyl substances make up a massive class of over 12,000 synthetic chemicals. Since the 1940s, manufacturers have added them to consumer products to resist heat, oil, stains, and water. You will find them in Teflon non-stick pans, Gore-Tex rain jackets, Scotchgard stain repellents, and industrial firefighting foams.

The defining feature of a PFAS molecule is a long chain of carbon and fluorine atoms. The carbon-fluorine bond is one of the strongest bonds in all of organic chemistry. Because this bond is so rigid, bacteria cannot eat the chemicals, and sunlight does not break them down. Instead, they accumulate in soil, drinking water, and human blood. Health organizations like the CDC have linked high levels of PFAS exposure to kidney cancer, testicular cancer, liver damage, and decreased vaccine response in children.

The problem is so severe that in April 2024, the Environmental Protection Agency (EPA) finalized strict new limits for PFAS in public drinking water, restricting levels of chemicals like PFOA to just 4 parts per trillion.

The Northwestern University Breakthrough

In August 2022, a research team at Northwestern University published a groundbreaking study in the journal Science. Led by chemistry professor William Dichtel and lead author Brittany Trang, the team discovered a chemical vulnerability in a specific, heavily used class of forever chemicals.

Instead of trying to force the tough carbon-fluorine bonds to break directly, the Northwestern team targeted the weaker end of the molecule. This creative approach represents a major shift in how scientists plan to clean up chemical waste.

How the Low-Temperature Chemical Process Works

The Northwestern method focuses on perfluoroalkyl carboxylic acids (PFCAs). These specific molecules feature a long tail of carbon and fluorine atoms attached to a “head group” made of oxygen. The researchers figured out how to chop off this oxygen head group using two common chemicals: sodium hydroxide (the main ingredient in household lye) and an inexpensive organic solvent called dimethyl sulfoxide (DMSO).

Here is exactly how the degradation process unfolds:

Chemists mix the targeted PFAS with sodium hydroxide and the DMSO solvent.
They heat the mixture to 120 degrees Celsius (about 248 degrees Fahrenheit).
The heat and the chemical mixture cause the oxygen head group to snap off, leaving a highly unstable molecule behind.
Once the head group is removed, the remaining carbon-fluorine tail begins to spit out fluorine atoms in a rapid cascade of chemical reactions.
Within 24 hours, the once-indestructible molecule completely falls apart.

Safe Byproducts

The destruction of the forever chemicals leaves behind surprisingly safe materials. The degraded PFAS molecules turn into fluoride ions, carbon dioxide, and formic acid. Fluoride is the same mineral added to toothpaste and public drinking water to prevent cavities. Carbon dioxide is naturally present in our atmosphere, and formic acid is a common organic chemical found in nature. The toxic threat is completely neutralized.

Why This Method Beats Current Disposal Techniques

To understand why this low-temperature method is so important, you have to look at how waste management facilities currently deal with PFAS. Right now, the industry mostly relies on high-heat incineration or deep-well injection.

Incinerators must heat the chemicals to temperatures exceeding 400 degrees Celsius, and sometimes up to 1,000 degrees Celsius, to successfully break the carbon-fluorine bonds. This requires a massive amount of fossil fuels and electricity. Furthermore, if the temperature drops even slightly, incomplete burning can send smaller toxic PFAS molecules flying out of the smokestack and into the surrounding air.

Alternatively, burying the chemicals in landfills does not solve the problem. The molecules eventually leach through the soil and contaminate local groundwater supplies. By operating at just 120 degrees Celsius, the new sodium hydroxide and DMSO method uses a fraction of the energy required by incinerators and prevents air pollution.

Which Specific Forever Chemicals Are Targeted?

The Northwestern process successfully breaks down 10 different types of perfluoroalkyl carboxylic acids. This includes PFOA, one of the most notorious forever chemicals that was used for decades in non-stick cookware and is now heavily restricted by the government.

The method also destroys GenX. Chemical companies created GenX as a safer replacement for PFOA, but it later proved to be just as toxic and persistent in the environment.

However, the researchers note that their current method does not work on perfluoroalkanesulfonic acids. These are PFAS molecules with a sulfur-based head group rather than an oxygen-based one. The most famous of these is PFOS. Scientists are actively searching for similar chemical vulnerabilities to destroy these sulfur-based variants.

The Future of Water Treatment and Environmental Cleanup

While this chemical decapitation process currently happens in a laboratory setting, the next step is scaling the technology for real-world application. Environmental engineers are looking at ways to integrate this chemical destruction method into industrial wastewater treatment plants.

Because lye and DMSO are cheap and readily available, cities could potentially pump PFAS-contaminated water through a filtration system to capture the concentrated chemicals. Once the chemicals are trapped, facility workers could run the 120-degree degradation process to destroy the toxins permanently on-site.

Frequently Asked Questions

What are forever chemicals? Forever chemicals are synthetic polyfluoroalkyl substances (PFAS) that contain incredibly strong carbon-fluorine bonds. They are used to make products water and stain-resistant. They do not break down in nature and build up in human bodies over time.

Why is 120 degrees Celsius considered low-temperature for this process? Traditional disposal methods require commercial incinerators to reach temperatures between 400 and 1,000 degrees Celsius to destroy PFAS. A temperature of 120 degrees Celsius is just slightly above the boiling point of water, making it vastly more energy-efficient and cheaper to achieve.

Can this method clean up the ocean or public drinking water right now? Not immediately. The chemical process currently requires researchers to isolate and concentrate the PFAS chemicals first. You cannot simply pour lye and DMSO into a lake or ocean. Future commercial applications will likely involve filtering the chemicals out of water supplies first, and then destroying the concentrated chemical waste inside a controlled facility.