Research Highlights Dual - Function of PFAS - Removing Water Technologies

A recent study has revealed that the technologies implemented for eliminating forever chemicals, specifically Per - and polyfluoroalkyl substances (PFAS), from drinking water, are performing an additional crucial function. These technologies are effectively removing other harmful materials, including certain substances associated with specific types of cancer. This research was published on Thursday in the journal ACS ES&T Water.

Regulatory Landscape Amidst PFAS Concerns

• The study emerges during a period when the Trump administration is in the process of overhauling a rule. This rule mandates that water systems take measures to clean up PFAS in drinking water. PFAS, commonly known as forever chemicals, consist of thousands of chemical compounds that do not break down in the environment. They have been linked to numerous health issues, such as various cancers, hormonal disorders, and developmental delays. A 2023 study by the US Geological Survey estimated that 45 percent of tap water in the US may contain at least one PFAS chemical, highlighting their widespread presence.

• In the previous year, the Biden administration finalized a rule establishing the first - ever legal limits for PFAS in drinking water. This rule set strict limits for six kinds of PFAS chemicals and required water utilities to clean up drinking water to meet these limits by 2029. However, in May, the Environmental Protection Agency (EPA) announced that it would be reconsidering regulations on four of the six chemicals in the original rule and extended the deadline by two years. This decision came in response to widespread protests from water utilities, which argued that the costs of installing PFAS filtration systems far exceeded the agency's initial estimates.

EPA's Stance on PFAS

• Brigit Hirsch, EPA press secretary, stated in a statement to WIRED: "Building on the historic actions to address PFAS during the first Trump Administration, EPA is tackling PFAS from all of our program offices, advancing research and testing, stopping PFAS from getting into drinking water systems, holding polluters accountable, and more. This is just a fraction of the work the agency is doing on PFAS during President Trump’s second term to ensure Americans have the cleanest air, land, and water." Hirsch also emphasized that as EPA reconsiders standards for the four chemicals in question, "it is possible that the result could be more stringent requirements."

Additional Benefits of PFAS - Removal Technologies

• Experts suggest that the costs associated with cleaning up PFAS may bring other benefits beyond merely eliminating forever chemicals from the American water supply. The authors of the new study, all employees of the Environmental Working Group (EWG), a nonprofit focused on chemical safety research, claim that technologies designed to remove PFAS can also filter out a variety of other harmful substances. Some of these substances are by - products of the water treatment process itself.

• The study examined three types of water filtration technologies that have been proven effective in removing PFAS. Sydney Evans, a senior analyst at EWG and co - author of the report, said, "These technologies are really widespread, they’ve been in use for a really long time, and they’re well - documented to remove a large number of contaminants."

Limitations of Conventional Water Disinfection

• In the US, most routine water disinfection processes involve adding a chemical, typically chlorine, to the water. While this process effectively removes harmful pathogens, it cannot remove PFAS or other contaminants such as heavy metals and arsenic. Paradoxically, this disinfection method can create harmful by - products as chlorine reacts with organic compounds in the water or in infrastructure like pipes. Long - term exposure to some of these by - products has been linked to specific types of cancer. Although there are federal guidelines for water utilities, experts note that an increasing body of research indicates a gap between what is legally acceptable and what is safe. It is not uncommon for utilities to find water samples exceeding legal limits; for example, officials in Springfield, Massachusetts, and Akron, Ohio, notified residents this year that their water was contaminated with disinfection by - products.

• Evans, whose past work has focused on the links between disinfection by - products and cancer, said, "There’s this gray area in between what is safe and what is legal where there’s still some risk, which is why we’re so concerned about all of these contaminants."

EPA's Recognition of Side Benefits

• In the 2024 PFAS drinking water regulations, the EPA specifically identified lower levels of disinfection by - products as a side benefit of the new PFAS rule. The agency estimated that the rules could prevent 2,600 additional deaths and more than 7,000 illnesses from bladder cancer each year due to advanced filtration systems. Evans and her co - authors aimed to conduct their own research to provide specific data to support these claims.

Study Methodology and Results

• The new research utilized publicly available state and national data from water utilities across the country. The researchers focused on a sample group of 19 water systems that had installed some form of PFAS treatment between 2018 and 2022. They compared trends in the concentrations of two separate disinfection by - products before and after the installation. The results showed significant reductions in the two types of by - products they tracked: The level of trihalomethanes dropped by an average of 42 percent, while haloacetic acid levels dropped by an average of 50 percent. High levels of trihalomethanes increase the risk of cancer in humans, and some haloacetic acids are suspected carcinogens.

Expert Opinions on the Study

• Experts not involved in the study consider it a solid confirmation of long - held scientific suspicions. P. Lee Ferguson, a professor of civil and environmental engineering at Duke University, said, "It’s really an interesting first effort to try to diagnose ancillary benefits—and perhaps unintended benefits—from installing advanced water treatment systems intended to remove PFAS. This gets at a question many of us have asked, and that I’ve thought about quite a bit: [with] the very act of installing advanced treatment intended to remove really recalcitrant contaminants like PFAS, you really do have the potential to get a lot of other benefits."

Disparities in Advanced Technology Adoption

• While developing the study's methodology, the researchers also highlighted the significant gap in advanced technology adoption between smaller and larger water systems. Only 7 percent of water systems serving fewer than 500 customers had some kind of advanced water filtration system, compared to nearly 30 percent of water systems serving more than 100,000 people. These smaller systems predominantly serve rural and under - resourced populations. Cost is a major factor, as these advanced technologies are much more expensive than chlorine - based water treatment. In May, the EPA announced the launch of an initiative called PFAS OUT, which will assist water utilities in need of upgrades by providing "tools, funding, and technical assistance."

Study Limitations

• Bridger Ruyle, an assistant professor of environmental engineering at NYU who studies PFAS and water systems, notes that the relatively small sample size of 19 water systems and the lack of detailed data result in some wide discrepancies in the results. Some systems in the study experienced a nearly complete reduction in disinfection by - products after installing advanced filtration, while at the other extreme, some water systems actually showed an increase in by - products. Ruyle emphasizes that this does not mean the technology is ineffective. Instead, it calls for more research into how variables such as new exposure sources and seasonality may affect specific water treatment plants. He stated, "In the lab, you can do all of these controlled studies, and you can say, ‘Oh yes, we eliminate all of the PFAS, and that also takes care of some other contaminant issues of concern.’ But when you’re talking about the real operation of a water facility, the environmental behavior of PFAS and these other chemicals are not the same. You could have different seasonal patterns, you could have different sources, you could have climate change impacting different components. And so, just because we’re treating a certain inflow of PFAS, a lot of other things could be happening to these other chemicals kind of independently."

The Cost Dilemma

• The question of cost remains a significant issue, particularly regarding who should bear the financial burden of cleaning up water. Across the country, water utilities are incorporating new PFAS testing and remediation measures into other necessary upgrades, leading to a significant increase in consumers' water bills. However, understanding the full benefits of these measures can help scientists and policymakers better chart the way forward. Ruyle commented, "This is an enormous financial challenge. And at the same time, it’s a financial need. There’s a big focus now in the Trump administration from the MAHA movement [around] what are these causes of all of these health and well - being ills. If you’re not willing to put up the money to upgrade infrastructure, to actually address proven causes of environmental harm, then what are we going to do?"