Per- and polyfluoroalkyl substances (PFAS), also known as "forever chemicals", are a large family of substances that have an enormous industrial application. They are so widespread that they have started to leach into the environments, and from there to humans and other animals. There are several health risks associated with the accumulation of these substances, and it is not easy to get rid of them once they enter the environment.
A new method to clean drinking water of these substances has now been unveiled by engineers at the University of British Columbia. The filters consist of an adsorbing material – and that's not a typo. Unlike absorbing material that gets soaked through, an adsorbing one keeps molecules on its surface. That's where the magic happens: The material can trap PFAS, and by using electric currents and chemical reactions powered by light, those molecules are destroyed for good.
"Our adsorbing media captures up to 99 percent of PFAS particles and can also be regenerated and potentially reused. This means that when we scrub off the PFAS from these materials, we do not end up with more highly toxic solid waste that will be another major environmental challenge," engineering professor Dr Madjid Mohseni, who developed the technology, said in a statement.
There are several places in the world that no longer manufacture the chemicals – but given how unreactive they are, they simply accumulate, so even in those locations contamination might be high. Dr Mohseni’s research group also focuses on developing water solutions for rural, remote, and Indigenous communities, and this approach doesn’t require massive filtering facilities.
"Our adsorbing media are particularly beneficial for people living in smaller communities who lack resources to implement the most advanced and expensive solutions that could capture PFAS," added Dr. Mohseni. "These can also be used in the form of decentralized and in-home water treatments."
The next step for this research is to be tested in the real world. From this month onward, Dr Mohseni and his team will be going to a number of locations in British Columbia to see how well the system works with regular water supplies.
"The results we obtain from these real-world field studies will allow us to further optimize the technology and have it ready as products that municipalities, industry and individuals can use to eliminate PFAS in their water," explained Dr. Mohseni.
The study is published in the journal Chemosphere.