Open this photo in gallery:New UBC catalyst removes ‘forever chemicals’ from water supplies before they can cause lasting harm. Researchers left to right: Dr. Raphaell Moreira, Pani Rostami and Dr. Johan Foster.UBC Applied Science/Paul JosephHave you worn a waterproof garment recently or used a piece of non-stick cookware? Chances are that those items were made with the help of per- and polyfluoroalkyl substances, also known as PFAS.“PFAS compounds are wonderful at what they do, but they last forever and that’s the problem,” explains Johan Foster, an associate professor of chemical and biological engineering at the University of British Columbia. “They don’t break down in nature and they’re soluble in water, so they accumulate in the human body.”These properties are what give PFAS the nickname of ‘forever chemicals’.PFAS are favoured for their ability to resist water, heat, grease and oil. However, tiny amounts of PFAS can cause serious health issues, including hormonal imbalances, developmental delays and increased risks of cancer in humans.The eradication solutions available, like heating PFAS-contaminated water to a high temperature, are expensive, consume a lot of energy and are impractical for large-scale use. There are also existing filtration systems that can trap PFAS but they don’t eliminate the substance.“That’s not a long-term option,” Foster explains. “You’re just kicking the can down the road.”The lightbulb momentIn 2022, while discussing PFAS with his colleague Madjid Mohseni, another UBC professor of chemical and biological engineering, Foster began brainstorming a scalable, economical and environmentally friendly way to not only trap but also break down the substance.Mohseni suggested looking into iron salts, which are known to break down the ultrastrong carbon-fluorine bonds in PFAS. This sparked an idea for Foster, who had already been experimenting with biochar in his lab – wood chips burned into charcoal, known for their high absorbency.“I figured, why can’t I just combine these two things: get iron salts onto wood and burn them,” Foster says.The first version of their PFAS biochar solution was created with the use of a blowtorch. Then, water contaminated with PFAS would be filtered through the treated granules of biochar, working similarly to a Brita filter.“It absorbs the PFAS, then the [iron salt] catalyst on there starts to break it down.” After their initial discovery, Foster’s lab continued experimenting with the solution.Refining the solution“We changed the salt concentrations, how we made them and the temperature we burn them at,” he explains, eventually landing on a product that was both effective, cheap and scalable. They even found ways to hasten the filtration process. “It is a photocatalyst, so if you shine a light on it, that will speed things up,” Foster says.Foster is currently working on developing a PFAS filtration system for homes and small businesses that would be affordable, costing between $50 to $200.“In the U.S., a lot of homes have a three or four-stage active charcoal water purification system,” Foster explains. “This is a new version of an activated charcoal filter that could also destroy PFAS.”Looking aheadSome time in 2025, Foster hopes to have a home filtration solution ready to buy. His next goal after that is to get municipalities on board to incorporate PFAS filtration into the water treatment systems for a city or town.“Activated carbon is already used in a lot of [municipalities] as one step in a water purification process,” he says. “At a municipal level, we can drop in our solution in an already existing system.”But seeing his solution used by municipalities could take years.“It’s very difficult to get into municipalities just because a lot of politics are involved,” he says. “But we are in talks with engineering firms that are experienced in creating solutions for municipalities.”PFAS are ubiquitous nowadays, and they play a critical safety role in safety applications, such as their use in fire retardants. But Foster’s solution offers hope for a future where water can be safely and permanently treated for PFAS on a wider level.“We’re trying to scale this up and prove that it works at all of these scales.”