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
De-mystifying common misconception about the prevalence of legionella bacteria
There is a common misconception that legionella is only found in air conditioners and water towers, however, Griffith University research has found people are likely exposed to the bacteria through other sources including through soil.
Associate Professor Lara Herrero from Griffith’s Institute for Biomedicine and Glycomics tested blood donor serum from Queensland donors to see if they were exposed to legionella bacteria which leads to Legionnaire’s disease, a serious form of pneumonia.
“We tested 1000 samples of blood, 500 from 2016 and 500 from 2023, to see if donors had antibodies against the bacteria,” Associate Professor Herrero said.
“These two windows of time were critical as Queensland observed an increase in Legionnaire’s disease cases in 2021-2022.
“The research assessed seroprevalence, or the level of pathogen in a population, as 2016 and 2023 represented before and after the higher incidence rate.”
The research found while Legionella prevalence remained stable, L.pneumophila, commonly found in air conditioning vents had decreased, while L. longbeachae (more commonly found in soil) had increased.
This is consistent with public health case numbers which show Legionellosis caused by L. longbeachae has dominated cases in the past five years.
“We know that L. longbeachae is prevalent in soil, so we should be aware of the possible exposure risk, especially when it comes to potting soils,” she said.
“We can all take measures to minimise our exposure when gardening or using potting soil such as wearing a mask.
“It is especially important for vulnerable individuals such as the elderly, immunosuppressed, or those with co-morbidities to take particular care.”
Legionnaire’s disease is an urgent notifiable condition which presents as a febrile illness or pneumonia, which may be severe.
Symptoms include fever, chills, cough, and shortness of breath.
Humans contract the infection via inhalation and is not spread from person to person.
Although relatively uncommon, Legionnaire’s disease may be life-threatening and is thought to be responsible for approximately five to 15 per cent of all community-acquired pneumonias.
The paper ‘Seroprevalence of antibodies against legionella species in North Eastern Australian blood donors, 2016 and 2023’ has been published in The Journal of Infectious Disease.
A new species of a native bushland marsupial – closely related to the kangaroo – has been discovered but is already likely extinct, new research shows.
Analysing fossils collected from caves of the Nullarbor and southwest Australia, researchers from Curtin University, the Western Australian Museum and Murdoch University uncovered a completely new species of bettong as well as two new subspecies of woylie.
Woylies are ecosystem engineers capable of turning over several tonnes of earth each year in search for their favourite mushroom treats. The cute kangaroo relatives, native to Western Australia, are the country’s most translocated mammal because they are moved as part of conservation efforts to save the critically endangered species.
Lead author Mr Jake Newman-Martin, a PhD student in Curtin’s School of Molecular and Life Sciences, said the discovery unlocked vital clues about the diversity of woylies, also known as brush-tailed bettong.
“Woylies are critically endangered marsupials that have been the focus of conservation efforts for decades,” Mr Newman-Martin said.
“In this new research, we’ve named a completely new species based on fossil material, and two new subspecies of woylies for the first time. Sadly, many of them have become extinct before we’ve even been aware of them.
“Our results split the critically endangered woylie into two living subspecies, which is very important for conservation when we’re considering breeding and translocation initiatives to increase the size and fitness of populations.”
Co-author Dr Kenny Travouillon, Curator of Terrestrial Zoology at the Western Australian Museum, said researchers used bone measurements to assess the diversity of woylies and the number of species.
“This research confirmed several distinct species and expanded the known diversity of woylies by measuring skull and body fossil material that had previously not been looked at in detail,” Dr Travouillon said.
“What we’ve found through this research tells us that examining fossils alongside genetic tools could offer significant insights that may help conservation efforts of this critically endangered native species.”
The scientific name of the new Nullarbor species has been described as Bettongia haoucharae but the researchers will work with Indigenous people to identify an appropriate collaborative name given woylie is a Noongar word.
The research examined specimens from the Western Australian Museum, South Australia Museum, Australian Museum, Queensland Museum, Museums Victoria, Flinders University research collection, Natural History Museum London, and Oxford University Museum of Natural History.
The full paper, titled ‘A taxonomic revision of the Bettongia penicillata (Diprotodontia: Potoroidae) species complex and description of the subfossil species Bettongia haoucharae sp. nov.’, was published in Zootaxa and can be viewed online here.
A taxonomic revision of the Bettongia penicillata (Diprotodontia: Potoroidae) species complex and description of the subfossil species Bettongia haoucharae sp. nov.
Article Publication Date
4-Sep-2025
Ash boosts biogas production
University of Jyväskylä - Jyväskylän yliopisto
White mustard (Sinapis alba L.) was used as an experimental crop, and the responses followed were seed germination, plant growth, and number of flowers.
Researchers from the University of Jyväskylä and the Natural Resources Institute Finland have discovered that ash appears to be an excellent additive in the anaerobic digestion process in terms of methane production and the fertilizing properties of the remaining digestate. The research results were recently published in a scientific journal Biomass and Bioenergy.
As the global population increases, efficient food production becomes more critical. Rising fertilizer needs and limited access to mined materials like phosphate -classified by the EU as critical raw materials- highlight the urgency of developing recycled alternatives from local side streams and waste.
- Anaerobic digestion is a well-known biological process where microorganisms break down organic material in the absence of oxygen, producing biogas and nutrient rich digestate. We wanted to find out how does addition of ash affect the biogas production in anaerobic digestion of biowaste and how are the fertilizing properties of the digestate affected, explains Senior Lecturer Siiri Perämäki from the University of Jyväskylä.
The positive effect of ash
Researchers noticed that ash can be used as an additive in anaerobic digestion of biowaste to increase methane production and improve the quality of the digestate as a fertilizer.
- However, too much ash can have the opposite effect on methane production, says principal scientist Saija Rasi from Natural Resources Institute Finland.
The study also found that the raw material used in the combustion process affects the quality of the ash and, consequently, methane production.
- Ash produced from wood combustion was more favorable than ash from peat combustion, which is probably due to the different trace element concentrations in the ash. Adding trace elements in the form of ash has a complex effect on the anaerobic digestion process and is very case-specific, depending on the type of ash, the raw material for anaerobic digestion, and the microbial community, Rasi explains.
Ash addition increased biomass, flowering and germination
The researchers also observed that ash increased plant growth in a growing trial with mustard plants. Adding ash affects the growing medium by increasing its nutrient and trace element content and organic matter, as well as reducing its acidity. Germination and flowering decreased in all growing media containing digestate but increased with the addition of ash.
- It is likely that the plants with digestate addition allocated more resources to growth than to reproduction. Heavy metal concentrations in growing media remained safe, and no harmful metal accumulation was observed in plants, says Perämäki.
The study shows that ash could be used both in biogas plants to optimize the process and to improve the quality of recycled fertilizers when used in appropriate amounts.
- This supports the principles of the circular economy and offers new opportunities for utilizing side streams, Perämäki notes.
The study was conducted as part of the KIRE project (Circular Economy Ecosystem: Waste and Side Streams as Raw Materials), which was funded by the European Regional Development Fund through the Council of Central Finland, the City of Jyväskylä, Mustankorkea LTD, Helsinki Region Environmental Services (HSY), Saarijärven Kaukolämpö LTD, and Kuopion Energia LTD. Part of the study was carried out as a bachelor's thesis by students at the Department of Environmental Science, which investigated the fertilizing properties of the digestate.
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.
