Forever Chemicals in Drinking Water

For decades, per- and polyfluoroalkyl substances (PFAS) have been dubbed “forever chemicals” because nature cannot break them down. They accumulate in our bodies and water supplies, posing significant health risks. However, a wave of scientific breakthroughs is shifting the narrative from containment to total destruction. New technologies are now moving out of the lab and into municipal water treatment plants to sever the toxic bonds of these chemicals permanently.

The Chemistry Behind the Crisis

To understand why new filtration methods are revolutionary, you first need to understand the enemy. PFAS are defined by the carbon-fluorine bond. This is one of the strongest bonds in organic chemistry. It is what makes Teflon pans non-stick and firefighting foam heat-resistant.

Unfortunately, this strength means the chemicals do not degrade naturally. Traditional water treatment methods, such as Granular Activated Carbon (GAC) or ion exchange resins, function like sponges. They soak up the PFAS from the water, but they do not destroy it. The result is a concentrated hazardous waste product—often saturated carbon filters—that must be buried in landfills or incinerated. Incineration can be dangerous because, if not done at incredibly high temperatures, it simply sprays the chemicals back into the air.

The new class of technology focuses on “mineralization.” This is the process of completely breaking the carbon-fluorine bond, turning toxic substances into harmless byproducts like carbon dioxide, water, and fluoride salts.

Supercritical Water Oxidation (SCWO)

One of the most promising technologies currently entering the market is Supercritical Water Oxidation. Companies like 374Water are leading this charge with units like the AirSCWO.

This technology relies on a fascinating state of physics. When water is pressurized to over 220 bars and heated above 374 degrees Celsius, it becomes “supercritical.” It is no longer a liquid or a gas but a distinct state of matter. In this state, organic compounds like PFAS become soluble, and oxygen becomes highly reactive.

The process works rapidly:

Contaminated water or sludge is pumped into the reactor.
The supercritical environment breaks the molecular bonds almost instantly.
The output is clean water, inert gases, and minerals.

Battelle, a massive nonprofit applied science and technology organization, has developed a similar system called the PFAS Annihilator. This mobile unit has been tested at wastewater treatment plants in Michigan to destroy PFAS in sewage sludge. Battelle reports that the Annihilator consistently destroys over 99.99% of PFAS chemicals without creating harmful byproducts.

Electrochemical Oxidation

Another front-runner in the race to clean municipal water is electrochemical oxidation. A startup called Aclarity is currently deploying this technology.

The science here is electrical rather than thermal. Water is passed between two electrodes (anode and cathode). A strong electrical current runs through the water, generating reactive species on the surface of the electrodes. These reactive species attack the carbon-fluorine bonds directly, zapping them apart.

This method is particularly attractive for “polishing” water—removing low levels of PFAS to meet the strict new standards. It operates at ambient temperatures and pressures, meaning utilities do not need to build dangerous high-pressure vessels on-site.

The UV-Sulfite Breakthrough

While high-energy physics gets a lot of attention, chemistry labs are finding more elegant solutions. Researchers at the University of California, Riverside, led by Associate Professor Jinyong Liu, discovered a method using ultraviolet (UV) light and sulfite.

Sulfite is a common, inexpensive compound used as a food preservative. When mixed with contaminated water and exposed to UV light, the sulfite releases hydrated electrons. These electrons act like “bond hunters,” specifically targeting the tough carbon-fluorine link in PFAS molecules.

This method is gaining traction because it uses commercially available equipment. Most water treatment plants already use UV light for disinfection. Adapting these systems to destroy PFAS by adding sulfite could be a cost-effective solution for cash-strapped municipalities.

HALT: Hydrothermal Alkaline Treatment

A technology known as HALT is being commercialized by a company called Aquagga. This process is specifically designed to handle the “concentrate” or “brine” left over from traditional reverse osmosis filters.

Reverse osmosis creates two streams of water: pure drinking water and a highly toxic, salty waste stream loaded with PFAS. Aquagga’s HALT system heats this waste stream to about 300 degrees Celsius and adds an alkali (like sodium hydroxide). The combination degrades the PFAS in minutes.

In 2024, Aquagga began deploying these units to clean up contamination at U.S. Air Force bases, which are historically major sources of PFAS pollution due to the heavy use of firefighting foams.

The Regulatory Driver: EPA's 2024 Mandate

The rush to adopt these technologies is not just about environmental stewardship; it is about compliance. In April 2024, the U.S. Environmental Protection Agency (EPA) finalized strict national drinking water standards.

The new rule sets enforceable Maximum Contaminant Levels (MCLs) for PFOA and PFOS at 4.0 parts per trillion (ppt). This is a near-zero limit, detectable only by highly sensitive equipment.

Public water systems have five years (until 2029) to implement solutions to reduce these chemicals if their levels exceed the standard. This mandate effectively forces the market to move away from simple storage of these chemicals and toward the destructive technologies described above.

Frequently Asked Questions

Does boiling water remove PFAS? No. Boiling water does not remove PFAS. In fact, boiling water can slightly increase the concentration of the chemicals because some of the water evaporates while the PFAS remains.

Do standard refrigerator filters remove forever chemicals? Generally, no. Standard refrigerator filters use a basic form of activated carbon designed to improve taste and remove chlorine. They are not dense enough or designed correctly to capture PFAS molecules effectively. You need filters certified specifically for NSF/ANSI Standard 53 or 58 for PFAS reduction.

Is bottled water safer than tap water regarding PFAS? Not necessarily. Bottled water is less regulated than municipal tap water in many jurisdictions. Studies have found PFAS in various major bottled water brands. However, some brands that purify water using Reverse Osmosis (RO) may have lower levels, provided the bottling facility maintains its membranes properly.

What is the difference between long-chain and short-chain PFAS? Long-chain PFAS (like PFOA and PFOS) have eight or more carbon atoms and bioaccumulate in the body for years. Short-chain PFAS have fewer carbon atoms. While short-chain versions stay in the body for less time, they are much harder to filter out of water because they do not “stick” to carbon filters as easily. Technologies like SCWO and electrochemical oxidation are vital because they destroy both types effectively.

How can I test my home water for these chemicals? You cannot use a simple dip-stick test like you would for pH or chlorine. Testing for PFAS requires sending a water sample to a certified laboratory that uses high-performance liquid chromatography. The cost typically ranges from $300 to $500 per test.