It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Thursday, September 04, 2025
Scientists review breakthrough methods to disrupt toxic “forever chemicals” in water
New study highlights recent advances in PFAS purification and outlines future sustainable strategies
Biochar Editorial Office, Shenyang Agricultural University
Per- and polyfluoroalkyl substances (PFAS), often called “forever chemicals,” are among the most persistent and harmful contaminants threatening global water safety. A new review published in New Contaminants provides the most comprehensive assessment to date of cutting-edge physicochemical technologies for PFAS removal, offering guidance for sustainable solutions.
PFAS are widely used in products such as non-stick cookware, food packaging, firefighting foams, and electronics manufacturing. Their remarkable stability makes them resistant to natural degradation, allowing them to accumulate in rivers, groundwater, and even drinking water supplies. Long-term exposure has been linked to liver disease, immune suppression, and developmental disorders, prompting increasingly strict regulations worldwide.
The review, led by researchers from North China Electric Power University and collaborators, summarizes major advances from the past three years across eight physicochemical approaches: adsorption, membrane separation, electrochemical treatment, UV-based oxidation and reduction, photocatalysis, thermal decomposition, ultrasonic oxidation, and plasma technology. These methods are capable of breaking PFAS’s notoriously strong carbon–fluorine bonds, achieving removal rates exceeding 90% in many cases.
“PFAS pollution is one of the most urgent environmental challenges of our time. By reviewing the latest advances in treatment technologies, we hope to provide researchers and policymakers with a roadmap for tackling these persistent pollutants,” said Mingxia Bai, first author of the study.
Despite the progress, the study emphasizes that significant challenges remain. High energy demands, incomplete mineralization, the formation of potentially toxic byproducts, and engineering scalability all limit real-world application. To overcome these barriers, the authors highlight three promising directions: integrating multiple technologies into synergistic systems, designing novel composite materials, and deepening mechanistic understanding of PFAS degradation.
“Our findings suggest that combining multiple treatment strategies and designing novel materials will be key to achieving efficient, low-carbon, and scalable PFAS remediation. This will be essential for protecting water resources and ensuring long-term environmental sustainability,” said Junfeng Niu, corresponding author of the study.
By charting these pathways, the review underscores the importance of developing high-efficiency, low-carbon, and scalable purification strategies to safeguard water resources and protect public health.
Journal Reference:
Bai M, Zhang Y, Zhang X, Song C, Cheng Y, Niu J. Disrupting the forever chemicals: cutting-edge physicochemical techniques for PFAS purification. New Contaminants. 2025;1:e002. doi: https://www.maxapress.com/article/doi/10.48130/newcontam-0025-0004
About the Journal:
New Contaminants is an open-access journal focusing on research related to emerging pollutants and their remediation.
WASHINGTON – Advanced systems for removing the toxic “forever chemicals” known as PFAS from drinking water can deliver far greater health benefits than previously thought. They also slash levels of other harmful contaminants, a new peer-reviewed Environmental Working Group study finds.
The research underscores the fact that PFAS water filtration systems can also help reduce levels of cancer-causing disinfection byproducts, or DBPs, agricultural nitrates and heavy metals like arsenic and uranium – all chemicals linked to health harms.
The study, published today in ACS ES&T Water, analyzed data from 19 U.S. utilities and the Environmental Protection Agency’s national water monitoring program. The findings show that PFAS removal technologies such as granular activated carbon, ion exchange and reverse osmosis can also lower levels of multiple harmful substances found in drinking water.
“PFAS treatment isn’t just about ‘forever chemicals,’” said Sydney Evans, EWG senior science analyst and lead author of the study. “It’s also opening the door to improving water treatment across the board.
“Advanced PFAS water treatment is a turning point that can help us clean up a broader mixture of contaminants and bring drinking water quality in line with today’s public health science,” added Evans.
A potential game-changer
In the 19 systems EWG studied, installation of advanced PFAS treatment technologies led to an average 42% drop in the level of trihalomethanes in drinking water, while haloacetic acid levels dropped 50%. Trihalomethanes and haloacetic acid are cancer-causing byproducts of water disinfection.
“DBPs and other harmful contaminants in drinking water are not emerging or unknown threats – we’ve known about them for a while. They’re regulated and they’re widespread,” said Varun Subramaniam, EWG science analyst and co-author.
“These kinds of reductions caused by PFAS filters are a game changer for public health, especially since where there are PFAS, there are always other chemicals, too,” he added.
EWG’s Tap Water Database, updated earlier this year, shows the extent of widespread drinking water contamination throughout the U.S. The study highlights the levels of several other contaminants in the countless communities relying on PFAS-polluted tap water.
Environmental injustice
EWG’s study also identified systemic inequities: Only 7% of very small water systems, defined as those serving fewer than 500 people, use advanced filtration. As a result, millions of Americans in rural and underresourced communities remain exposed to PFAS, hazardous disinfection byproducts and heavy metals.
By contrast, 28% of the largest utilities use the technology.
“This is a textbook case of environmental injustice,” Subramaniam said. “The communities least able to afford advanced filtration often face the highest health risks. Without targeted investment, these gaps will only widen.”
The research underscores an urgent need to rethink U.S. water policy. Most pressing is a shift away from one-chemical-at-a-time regulation toward holistic strategies that protect the full spectrum of pollutants. This work should start in the communities that need it most.
“This study exposes a dangerous blind spot in federal water policy,” said Melanie Benesh, EWG vice president of government affairs. “Communities wouldn’t just filter out PFAS, they’d be eliminating multiple toxic chemicals at the same time.”
“By ignoring these co-benefits, the EPA is leaving Americans exposed and missing a huge economic and public health opportunity,” Benesh said.
Regulatory setbacks threaten progress
The findings come amid backlash over the EPA’s recent rollbacks, including a plan to weaken long-sought protections against forever chemicals in drinking water.
In May, less than a full year after new standards were finalized, the EPA announced it would weaken key limits on four PFAS in drinking water and delay compliance deadlines. Critics say the pending rollback could prolong harmful exposures, particularly in communities unable to implement PFAS treatment technology independently.
EWG’s study also flags major gaps in national water monitoring. Inconsistent reporting to the EPA’s monitoring program hinders tracking co-occurring contaminants and evaluating treatment effectiveness. Standardized, nationwide monitoring and treatment-focused regulations would better reflect real-world water contamination patterns.
Despite the costs of installing advanced PFAS treatment, EWG’s research underscores the outsize public health returns of removing multiple hazardous contaminants at once. Today only 8% of U.S. water systems are equipped with filters capable of getting PFAS out, leaving millions of Americans – especially in small and rural communities – vulnerable to health risks.
Health risks of PFAS exposure
PFAS are toxic at extremely low levels. They are known as forever chemicals because once released into the environment, they do not break down, and they can build up in the body. The Centers for Disease Control and Prevention has detected PFAS in the blood of 99 percent of Americans, including newborn babies.
For over 30 years, EWG has been dedicated to safeguarding families from harmful environmental exposures, holding polluters accountable, and advocating for clean, safe water.
EWG’s study urges federal and state leaders to:
Boost federal and state funding for advanced filtration in under-resourced systems.
Strengthen national water monitoring to guide smarter policies.
Adopt regulations that account for co-occurring contaminants and expand public health protection.
“This isn’t just about PFAS,” said Evans. “When we fix one problem, we can solve several others. The opportunity to protect public health at scale is too big to ignore – if we’re smart about it.”
###
The Environmental Working Group is a nonprofit, non-partisan organization that empowers people to live healthier lives in a healthier environment. Through research, advocacy and unique education tools, EWG drives consumer choice and civic action.
An illustration of a PFAS breakdown product in its negatively charged and neutral forms, depicted in a dynamic back-and-forth between these states. The accompanying chart illustrates a plot that allowed a University at Buffalo-led team to determine its acid dissociation constant or pKa.
BUFFALO, N.Y. — One of the ways that per- and polyfluoroalkyl substances (PFAS) earn their “forever chemical” nickname and persist in the environment is their acidity.
Many of these toxic chemicals are highly acidic, meaning they easily give up their protons and become negatively charged. This allows them to dissolve and spread in water more easily.
Now, new research has found that some PFAS are even more acidic than previously thought — an insight critical for predicting their mobility in the environment and potential impacts on human health.
It comes from a University at Buffalo-led team that introduced a new and rigorous experimental method to determine the acidity of 10 types of PFAS and three of their common breakdown products.
Published last month inEnvironmental Science & Technology Letters, their measurements of these chemicals’ acid dissociation constant, or pKa, were mostly lower, in some cases dramatically, than those reported in experimental studies and predicted by computational chemistry models. In one case, the pKa of GenX, a replacement for perfluorooctanoic acid (PFOA) in the manufacturing of Teflon, was found to be about one thousand times lower than the measurement listed in a previous study.
The lower the pKa, the more likely a chemical is to give up a proton and exist in its charged form.
“These findings suggest that previous measurements have underestimated PFAS’ acidity. This means their ability to persist and spread in the environment has been mischaracterized, too,” says the study’s corresponding author, Alexander Hoepker, PhD, a senior research scientist with the UB RENEW Institute.
More accurate pKa measurements help efforts to understand the behavior of PFAS in the environment. A chemical’s pKa could mean the difference as to whether it remains dissolved in water, sticks to soil or a biological membrane or perhaps volatilizes into the air.
“If we’re going to understand how these concerning chemicals spread, it’s very important we have a reliable method for the accurate determination of their pKa values,” says Diana Aga, PhD, director of RENEW and SUNY Distinguished Professor and Henry M. Woodburn Chair in the UB Department of Chemistry.
The work was supported by the National Science Foundation and done in collaboration with Scott Simpson, PhD, professor and chair of the St. Bonaventure Department of Chemistry, and researchers from Spain’s Institute of Environmental Assessment and Water Research.
Combining experiments with computations
PFAS are made of a highly fluorinated, water-repelling tail and a more water-loving headgroup. Many of the most scrutinized PFAS have a highly acidic headgroup, making them more likely to give up a proton and exist in its charged form.
Whether a PFAS exists in its neutral or charged form depends on the pH level of their surrounding environment. That’s where pKa comes in. It tells scientists the pH level at which a given PFAS is equal to flip from neutral to charged, or vice versa.
But there has been much disagreement about the pKa measurements of some PFAS, like PFOA, with different teams coming up with widely different values. One of the reasons for this may be the glass used during their experiments.
“PFAS likes to stick to glass. When that happens, it throws off traditional, so-called bulk measurements that quantify how much PFAS is in a solution,” Hoepker says. “In other cases, too much organic solvent is used to get PFAS into solution, which similarly biases the pKa measurement.”
To address this challenge, the UB team used fluorine and proton (hydrogen) nuclear magnetic resonance (NMR) spectroscopy — think MRI for molecules. NMR places a sample in a strong magnetic field and probes its atomic nuclei with radio waves.
When a PFAS headgroup is negatively charged, nearby fluorine atoms respond at a different (radio) frequency.
Reading these atom-level signatures lets the researchers tell whether a PFAS molecule is charged or neutral — capabilities that other methods that have been used previously cannot provide.
“This unique measurement allows NMR to inherently account for PFAS losses to glass or other adsorption behaviors, so your pKa measurements don't end up way off the mark,” Hoepker says.
Some PFAS are so acidic (pKa of less than zero) that generating them in their neutral form would require super-acidic conditions (a pH level of less than zero) that are impractical in standard labs. In those cases, the research team paired NMR experiments with electronic-structure calculations using density functional theory to predict the NMR shifts of the neutral and ionized forms.
“We augmented partial NMR datasets with computational predictions to arrive at more accurate pKa values,” Hoepker says. “This NMR-centered hybrid approach — integrating experimental measurements with computational analyses — enhanced our confidence in the results and, to our knowledge, has not previously been applied to PFAS acidity.”
Problem PFAS measured more accurately
The PFAS that has been the most difficult to measure is PFOA, once commonly used in nonstick pans and deemed hazardous by the Environmental Protection Agency last year.
The team found its pKa to be –0.27, meaning it will be negatively charged at practically any realistic pH level. Previous experimental studies had measured its pKa as high as 3.8 and more commonly around 1, while the computational methods COSMO-RS and OPERA had determined its pKa at 0.24 and 0.34, respectively.
Trifluoroacetic acid (TFA) — an emerging PFAS increasingly detected in waters worldwide and likely transported through the atmosphere and deposited by rain — was found to be far more acidic than previously reported, with a pKa of around 0.03. Earlier estimates had anywhere from 0.30 to 1.1.
Notably, the team determined the pKa values for several prominent emerging PFAS that had never been measured, such as 5:3 fluorotelomer carboxylic acid (5:3 FTCA), and PFAS ethers like NFDHA and PFMPA that are newer PFAS but are also likely to pose challenges for regulators due to their health effects.
“This new experimental approach of determining pKa values for PFAS will have wide-ranging applications, from being able to validate computationally derived values, to facilitating the development of machine learning models that can better predict pKa values of newly discovered PFAS contaminants when reference standards are not available,” Aga says. “In turn, knowledge of the pKa values of emerging PFAS will allow researchers to develop appropriate analytical methods, remediation technologies, and risk assessment strategies more efficiently.”
Aside from Simpson, other co-authors include Silvia Lacorte, a senior scientist with the Spanish Institute of Environmental Assessment and Water Research; Aina Queral Beltran, a University of Barcelona PhD student and former visiting student at UB; and UB Chemistry graduate students Damalka Balasuriya and Tristan Vick.
Endocrine-disrupting chemicals (EDCs) encompass a class of substances capable of interfering with the endocrine system, thereby inducing diseases and functional irregularities in organisms. These substances are widely used in commercial and personal care products and have been frequently found in the aquatic environment worldwide.
As a pivotal protected area, the National Aquatic Germplasm Resources Reserve (NAGRR) in China designates special protection and management areas for specific tidal flats and related lands, with a focus on key growth and reproduction regions such as spawning. The Guangdong−Hong Kong−Macao Greater Bay Area is a highly developed and industrially active region in China, harboring a populace exceeding 87 million and a GDP surpassing RMB14 trillion. Notably, being adjacent to the South China Sea and centering around the Pearl River Estuary, this area encompasses three important marine NAGRRs. To address the current research gaps regarding the EDCs in these NAGRRs, a study published in the KeAi journal Environmental Chemistry and Ecotoxicology, a group of researchers from China examined the pollution levels of 31 common EDCs within these protected areas and their adjacent coastal areas.
The team found that EDC pollution levels were notably higher during the dry season compared to the wet season, with notable spatial variances observed among different regions. Environmental estrogens was the primary EDCs of concern, potentially disrupting the endocrine systems of aquatic organisms within these regions. Norgestrel, 17α-ethinylestradiol, 4-tert-octylphenol, bisphenol A, bisphenol B, and bisphenol F were all identified as pollutants.
The researchers proposed that initial efforts should be directed towards reducing the release of EDCs into the environment of marine protected areas at the source. This can be achieved through enhancements in sewage treatment plant processes, such as implementing more efficient secondary treatments like aerobic bioreactors. Further, chemical industry should be encouraged and incentivized to produce more environmentally friendly substitutes for replacing harmful EDCs in future. Research efforts to understand the toxicological impacts on benthic marine organisms exposed to these EDCs should also be stepped up.
Finally, at the management and policy level, marine NAGRRs need to bolster monitoring and early warning systems for priority EDCs within the region. When selecting sites for new NAGRR establishments, the authors note that the criteria for evaluating site suitability should incorporate indicators of environmental EDCs and distances from sewage treatment plants and urbanized coastal cities.
###
Contact the author: Yuefei Ruan, State Key Laboratory of Marine Environmental Health and Department of Chemistry, City University of Hong Kong, Hong Kong 999077, China, yruan8@cityu.edu.hk
The publisher KeAi was established by Elsevier and China Science Publishing & Media Ltd to unfold quality research globally. In 2013, our focus shifted to open access publishing. We now proudly publish more than 200 world-class, open access, English language journals, spanning all scientific disciplines. Many of these are titles we publish in partnership with prestigious societies and academic institutions, such as the National Natural Science Foundation of China (NSFC).
Madrid, Spain – 29 August 2025: Updated ESC Guidelines, published today at ESC Congress 2025, put a focus on a woman’s autonomy in making her own reproductive choices by promoting a transparent dialogue and shared decision-making for pregnancies that are high-risk for an adverse maternal and/or foetal event.
The guidance moves away from advising women with rare health conditions that make their pregnancy high-risk, (such as vascular Ehlers-Danlos syndrome and pulmonary arterial hypertension), against pregnancy. Instead, the guidelines recommend that women should receive counselling about the high-risk nature of their pregnancy by a multidisciplinary team, which takes into consideration their genetic background (if applicable), family history and previous vascular events.
The updated ESC Guidelines have been produced by an international panel of experts that include co-Chairpersons Professor Julie De Backer, Cardiologist and Clinical Geneticist from the Department of Internal Medicine and Paediatrics at Ghent University and Professor Kristina Hermann Haugaa, Cardiologist and Head of the Outpatient Clinic and Unit for Genetic Cardiac Diseases at Dept of Cardiology, Oslo University Hospital and University of Oslo.
Professor Julie De Backer explained, “More women with a history of cardiovascular disease are considering pregnancy. This is for many reasons such as more women who were born with heart conditions are surviving to adulthood, a greater number of women who have had a transplant or cancer treatment, and more women with acquired heart disease. This guidance gives clinicians and patients clear, and accessible advice based on the latest evidence.”
“In our updated guidance, we have shifted away from a rigid “pregnancy is forbidden” policy in high-risk cases to a model of shared decision-making, allowing women to make fully informed choices with appropriate psychosocial support,” Professor De Backer added.
Maternal cardiovascular disease is now the leading cause of non-obstetric mortality in pregnant women, accounting for 33% of pregnancy-related deaths worldwide. 68% of pregnancy-related deaths caused by cardiovascular disease are preventable. Up to 4% of pregnancies are complicated by cardiovascular disease globally, rising to 10% when including high blood pressure disorders. Reducing maternal mortality and morbidity is a key priority of the World Health Organization (WHO).
The updated ESC Guidelines recommend that a personalised pregnancy-related risk assessment is needed in all women with cardiovascular disease. This should include reviewing their medical needs, medication and wider factors including maternal age, smoking history, comorbidities, body mass index (BMI), obstetric history and socio-economic status. The guidelines recommend that maternal preferences should be thoroughly explored as part of the shared decision-making process.
The ESC Guidelines recommend discussions about the risks of pregnancy from puberty for young women with congenital or inherited heart disease. This is because of the high rates of unintended pregnancies, up to 45%, which have been reported in adolescents with congenital heart disease.
New guidance has also been given about medication used to treat women with cardiovascular disease during pregnancy, for example encouraging the use of statins throughout pregnancy for some women. There are also updates to the recommended medications for high blood pressure during pregnancy, and more detailed guidance on medication in cardiogenetic disorders.
“Due to limited data on medications tolerable in pregnancy, pregnant women are at risk of receiving sub-optimal treatment. Our guidelines give detailed and up-to-date guidance to ensure that important medication is not withheld unnecessarily. We hope that health care providers and patients will find the guideline useful and that it will reach a wide clinical audience,” Professor Kristina Hermann Haugaa said.
The important role of Pregnancy Heart Teams to support women’s mental and physical health before, during and after pregnancy is highlighted by the updated guidance. Pregnancy Heart Teams are associated with lower maternal death rates, lower hospital readmission rates and improved patient safety. The guidelines recommend that Institutional Pregnancy Heart Teams should be established in specialist hospitals, tailored to the geographical area, numbers of births and sociocultural factors.
“Too often women who would benefit from care by a specialised Pregnancy Heart Team are not referred in time. Conversely, some women are referred unnecessarily, thereby putting strain on these services. This guidance clearly defines which women should receive care from a Pregnancy Heart Team,” Professor Kristina Hermann Haugaa concluded.
The updated ESC Guidelines also:
Give clearer information about when caesarean sections are appropriate in women with cardiovascular risk. The updated guidelines note that women with cardiovascular risk often receive caesarean sections without evidence that this reduces risks, and despite evidence that suggests it may even increase foetal risk.
Recommend postponing pregnancy for at least one year after heart transplantation, taking individual risk factors into account.
Provide a more nuanced risk assessment for patient counselling responding to new data.
The ‘2025 ESC Guidelines for the management of cardiovascular disease and pregnancy’ have been endorsed by the European Society of Gynecology and replace previous guidelines from 2018.
Pregnancy is a high-risk period for women with cardiovascular disease, due to the physiological changes in heart and blood system needed to meet the increased metabolic needs of the mother and foetus. From the sixth week of pregnancy stroke volume and cardiac output increase in women by 30%–50%, and heart rate increases by 10–20 beats per minute. In women with heart disease, the adaptions needed from the heart can be faulty and can lead to heart failure and atrial and ventricular tachyarrhythmias.
ENDS
NOTES TO EDITOR
Funding: Not applicable
Disclosures: None
References and notes:
In high income countries, the number of pregnant women with cardiovascular disease is growing. This is due to several factors, such as higher maternal age at first pregnancy, a growing number of women with congenital heart disease reaching childbearing age, and a rising prevalence of cardiovascular comorbidities.
The guidelines “Cardiovascular disease during pregnancy ” will be discussed during the session “2025 ESC Guidelines and Document overview” Friday 29 August at 9:09 am CEST in room Madrid.
A dedicated ESC Guidelines Press Q&A session, featuring the task force chairs, will take place in the Press Area on Friday 29 August, at 12:00 CEST.
It is the world’s largest gathering of cardiovascular professionals, disseminating ground-breaking science both onsite in Madrid and online – from 29 August to 1 September 2025. Explore the scientific programme. More information is available from the ESC Press Office at press@escardio.org.
The ESC brings together healthcare professionals from more than 150 countries, working to advance cardiovascular medicine and help people to live longer, healthier lives.
