From mapping to air bubbles: How local researchers are tackling PFAS in Philly’s water

“Forever chemicals” are in Philly’s waterways. Research teams are tracking contamination and testing new ways to clean drinking water.

While we may not brag about it as much as New York City, Philadelphia has safe tap water. But, like other major cities around the country, Philadelphia does need to contend with PFAS in its drinking water sources, including the Schuylkill and Delaware Rivers, which together supply water to the city’s 1.7 million residents. 

PFAS, aka per- and polyfluoroalkyl substances, are a type of synthetic (aka human-made) chemicals that are widely found in industrial applications and consumer goods, including firefighting foam, water-resistant items, stain-resistant furniture, nonstick cookware, cosmetics, and more.

“One study found that dermal contact is actually a big route. It’s been found in fitness bands, or in chemical products you put on your skin, like makeup in some cases,” Samantha McBride, Assistant Professor of Mechanical Engineering and Applied Mechanics at the University of Pennsylvania, said to Green Philly. “It’s also in our food. If you’re eating fast food containers, usually those are always treated with PFAS on the wrappers to prevent grease intrusion and dripping out of the bottom.”

One route to exposure is our drinking water. That’s because these “forever chemicals,” a nickname given because PFAS cannot break down naturally and instead linger in the environment for thousands of years, can travel into the rivers from landfills, sewage systems, pollution, and factories.

The Philadelphia Water Department (PWD) monitors PFAS activity in Philly’s drinking water via three treatment plants. Although PWD has detected them in the Schuylkill and Delaware Rivers, they report that the city’s drinking water “meets all current state and federal regulations for PFAS.”

Researching PFAS in Philly

At least two research groups have also been trying to answer the questions of where PFAs are found in our city’s water, and how to best get them out.

McBride is a part of the Philly Emerging Water Contaminants Initiative, a research community at the University of Pennsylvania. Founded about a year ago due to strong student demand, McBride said they have trained students who are sampling different waterways around Philadelphia and running research projects.

“Because test(ing) for these contaminants is quite expensive, the average person can’t access it,” she said. “You want to know how many microplastics are in your water? You can send them off to a company and get it done for, like, $500. It’s quite expensive. So we’re hoping to kind of make that more accessible by providing access to this equipment we have at the University of Pennsylvania.”

Some students hope to create a map of Philadelphia that shows where they have sampled and what they found in those locations. They are also bringing in researchers from Temple University and Drexel University and are looking to further expand outside to the suburbs of Philadelphia.

Another big part of the plan is to talk to the community and get their input on their concerns.

“We really try to build a community of people who are interested in this research, and then also interested in kind of community-oriented solutions, bringing awareness to people, hopefully alleviating some of their concerns in some places,” McBride said.

The research itself is limited to the researchers within the universities, but McBride said that she has hopes to expand to potentially high school students or run “citizen science” classes at community centers to teach various environmental topics. 

A simple solution to remove PFAS

Then there’s Saiful Islam, a PhD student in Temple’s environmental engineering program, and Gangadhar Andaluri, assistant professor of civil and environmental engineering at Temple. They are working on a sustainable way to remove PFAS from water: Using air bubbles.

Right now, there are ways to treat water for PFAS using activated carbon or reverse osmosis membranes (which force water through very small pores under pressure to separate it from all the bad gunk). These are often energy-intensive.

“We work with faculty at the University of New Hampshire, the community there was seeing this formation of foam on the rivers. So essentially, that is, nobody added any cationic surfactants over there,” Dr. Andaluri told Green Philly. “So we thought, why not see what exactly could be in that water which is causing that natural foaming … we wanted to see if we can find something that would be helpful in generating that foam without using any toxic chemicals. That way, we could potentially use it for drinking water.”

They found that the foam on the surface had a higher concentration of PFAS than the water below it. From there, they began to experiment if they could manufacture this themselves to remove PFAS and microplastics from the water.

“PFAS have hydrophobic tails, meaning they are repelled by water,” said Saiful in an interview with Temple. “We thought if we could introduce air bubbles to the water, then the hydrophobic tail would be attracted to the bubble and get trapped on its surface. As the bubbles rise, they carry the interacted contaminants, PFAS and microplastics, and we can then remove the foam and the contaminants from the surface of the water.”

The idea is also more sustainable than some current methods. For every 100 gallons treated, one gallon of contaminated foam would remain. That foam would then be safely treated.

Dr. Andaluri warned that this work is still in early stages. “We still have to optimize some of these techniques, and then we might be able to do some pilot testing before anybody really even thinks about implementing it at a much larger scale,” he said.

Unfortunately, microplastics, or small plastic pieces, can also absorb PFAS and carry them. The EPA’s new federal regulations for PFAS do not include microplastics. Islam and Dr. Andaluri are hoping to address both.

“Initially, we were focusing only on PFAS, but when we were trying to remove PFAS, we observed that the microplastic was also removed,” said Islam in an interview. “We did several experiments on the interaction between microplastics and PFAS, and we observed that most of the PFAS absorbed onto the surface of the microplastics. So after that, we focused on the interaction of the contaminants.”

Ongoing regulations

Philly and its surrounding areas have a long history of chemical production. But PFAS aren’t exclusive to our area: they’ve even been found in remote places like the Arctic. PFAS exposure is linked to cancers, reproductive disorders, inflammation, and other medical issues. Once in our bodies, they remain there for years.

Both the state of Pennsylvania and the Environmental Protection Agency (EPA) both have set drinking water standards for some PFAS substances. In 2024, the EPA set new limits on PFAS levels in drinking water and will require all public water systems to begin monitoring these new levels by 2031.

PWD stated that they are “already in the planning and piloting stages to upgrade our treatment plants with the best and most cost-effective available technologies to meet the more stringent federal regulations when they go into effect.“

How to avoid PFAS at home

One way to avoid PFAS? Don’t litter. “This stuff should not be entering the waterways in the first place, said McBride. “Try to eliminate your use.”

The biggest product to try to put down? Plastic bottles.

 “Occasionally, having a beverage from a disposable that’s fine, but if you’re chronically drinking out of these beverages, it is going to affect your health, McBride explained.”

And these aren’t the only two groups fighting to leave the world a little less plastic. Another Philly group, Senior Environment Corps, is also tracking microplastics here in Phill Volunteer-led Plastic-free Philly through The Academy of Natural Sciences of Drexel University is also trying to eliminate those plastic water bottles McBride mentioned.

Photo: Pixabay