Researchers at Temple University are testing a way to sustainably filter out contaminants from drinking water — a technology that, if successful, could potentially reduce public health risks at a lower cost for water providers.

Md Saiful Islam, a doctoral student at the College of Engineering, uses air bubbles to capture microplastics and per- and polyfluoroalkyl substances (PFAS) at the water’s surface, allowing the contaminants to be removed without using toxic chemicals. He received a 2025 award from the Temple University Office of Sustainability to research removal technology for microplastics and PFAS.

“If we will focus on only one contaminant, then it can be an incomplete removal,” he said. “Because microplastics, PFAS and other contaminants exist in our environment, and they interact with each other. Over time, this interacted PFAS can release from the microplastic.”

Islam presented his technology during a November showcase at the College of Engineering and he received the Innovation and Collaboration Award from the Water Resources Association of the Delaware River Basin. His research on PFAS and microplastics has been published in peer-reviewed journals.

PFAS, a group of chemicals present in a wide range of consumer products, are known as forever chemicals because they don’t break down and are able to stick around in the environment. Studies have shown exposure can increase peoples’ risk of certain types of cancer and birth defects. Microplastics are widespread in food and drink products, and research suggests exposure to them can be linked to various health risks.

The Environmental Protection Agency (EPA) is mandating that water utilities phase out certain types of PFAS in drinking water by 2031. There are no standards for microplastics. Islam said his water treatment technology could help companies meet the EPA’s compliance deadline. He is testing six PFAS compounds.

“It can solve both things. It can save our human body as well as our aquatic system and utilities can fulfill the requirement of regulation,” he said.

Islam uses air bubbles to make foam at the water’s surface. PFAS have hydrophobic tails, which are repelled by water, he said. Islam considered that the tails would latch onto the air bubbles instead, causing the PFAS to be carried to the surface and concentrated in the foam. Most environmentally prevalent microplastics have hydrophobic surfaces that cause them to attach to the rising air bubbles, as well.

The foam would then be removed from surface water.

He and Gangadhar Andaluri, his faculty adviser, are now testing their method on the Schuylkill and Delaware rivers to see if it will remove all the PFAS. His foam-based technology has been able to remove nearly 100% of certain PFAS and microplastics. Some PFAS were removed after around two hours in the reactor, while others needed two to three days.

“We are still in those initial phases [of research], but as of now, Saiful is seeing almost 100% removal of some of the PFAS, although it might be taking a lot of time. That’s where we want to optimize technology to make the removal much faster,” Andaluri said.

Andaluri, an assistant professor of civil and environmental engineering at Temple, said this process, called foam fractionation, is being used to treat PFAS at a few groundwater and industrial sites. But companies and utilities use additives called surfactants, like soap, which can make the drinking water toxic. Air bubbles create foam, but they need help from surfactants to keep it stable.

“Our focus is mostly trying to find some of these nontoxic, plant derived surfactants that we could potentially add in and don’t create any issues in the water treatment,” he said.

Andaluri said their method is more sustainable because it doesn’t apply toxic chemicals. It also removes both PFAS and microplastics.

Another PFAS-removal method that drinking water utilities use today is granular-activated carbon technology, which transfers PFAS from the water onto carbon. It is one of the most efficient technologies available right now, but it produces hazardous waste and is energy intensive.

Andaluri said the technology also has the potential to be more cost effective than granular-activated carbon technology and other current methods.

Some industrial facilities use a process called supercritical water oxidation to remove PFAS, which involves high capital and operational costs. Islam only uses that process to remove the contaminated foam, which makes up just 1% of the treated water, while plants use it to treat all of the water.

The goal is to filter out these contaminants before they enter the water treatment plant to increase efficiency.

In the future, they hope to partner with drinking water plant utilities to conduct more tests.

It’s a positive step for Islam, who worked as a consultant on water contaminants prior to Temple. Andaluri recently spoke about PFAS at the American Public Health Association Annual Meeting and Expo.

“Getting exposed to PFAS could be multiple routes. One of the routes is through water, so if you’re able to remove at least one of the routes, it feels great to be doing that,” Andaluri said.