TORONTO, Oct. 22, 2026 鈥� A total of 175 91亚色 graduate students, along with 14 postdoctoral researchers, will receive more than $14 million through the (CRTAS), announced today by the federal government.

Today鈥檚 announcement highlights award winners funded through the , administered by the (CIHR), the (NSERC), and the (SSHRC).

鈥淚nvesting in emerging researchers is an investment in Canada鈥檚 future,鈥� says Lisa Philipps, interim president and vice-chancellor of 91亚色. 鈥淚 congratulate all of this year鈥檚 recipients. Their work in health, science, the arts and beyond shows the reach of 91亚色 research and its power to drive positive change in our communities.鈥�

For the (CGRS M), 96 91亚色 students will each receive $27,000 for 12 months, seven funded through CIHR, 18 through NSERC and 71 through SSHRC.

For the (CGRS D), 79 91亚色 students will each receive $40,000 per year for 36 months, nine funded through CIHR, 18 through NSERC and 52 through SSHRC.

鈥�91亚色鈥檚 graduate students and postdoctoral researchers are making important contributions to research that deepens our understanding of the world and helps address complex challenges,鈥� said Alice MacLachlan, vice-provost and dean of the Faculty of Graduate Studies. 鈥淭hese awards recognize the excellence, creativity and dedication of emerging researchers while providing valuable support to advance their work. Their achievements reflect the strength and breadth of graduate and postdoctoral research at 91亚色.鈥�

Program of study for both the CGRS M and the CGRS D students include disciplines in health, science, art, social sciences and humanities, engineering, the environment and more. This year, as 91亚色 prepares to open its new School of Medicine in 2028 (pending accreditation), it has nine CGRS D recipients in health, six more than the previous year.

For the (CPRA), worth $70,000 per year for 24 months, 14 91亚色 researchers were awarded.

The awards promote and support high-quality research leading to high impact careers. Altogether, more than $480 million through the CRTAS.

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TORONTO, Sept. 01, 2026 鈥� Coastal residents may be worried about exposure to forever chemicals from sea spray during hot summer months, but 91亚色 researchers found there was little evidence of per- and polyfluoroalkyl substances (PFAS) contamination from marine aerosols, a finding that surprised them.

The study looked specifically at areas impacted by sea spray from the Atlantic Ocean generated by waves breaking on the coast of Newfoundland and Labrador, however, despite its windy, marine location they found it was not an issue as previously thought.

鈥淲e designed this study specifically to see if sea spray was contributing to a mobilization of PFAS in coastal regions and Newfoundland is a great place to do that. It's a marine location and it鈥檚 very windy so we expected there to be quite a lot of PFAS from sea spray,鈥� says senior author Professor , an atmospheric chemist and Guy Warwick Rogers Chair in 91亚色鈥檚 Faculty of Science. 鈥淲e were quite surprised we didn't see anything that would indicate sea spray was contributing to PFAS in the area.鈥�

Earlier international studies using mainly modelling and lab work had found sea spray to be a significant and direct source of forever chemicals. Lead author 91亚色 PhD student Daniel Persaud, Young and the team conducted field work on the ground to understand the extent of the problem, expecting their results to support the former findings, but that is not what happened.

The researchers collected and analysed both wet and dry deposition samples from precipitation, such as rain, and dust that settled on the ground from particles and gases in the atmosphere at several locations up to 30 kilometres from the eastern coast. The researchers focused on forested watersheds in the Newfoundland and Labrador Boreal Ecosystem Latitudinal Transect, which are all influenced by marine aerosols and were selected because of their proximity to the ocean.

鈥淏ecause the sites are windy and close to the ocean, we expected a strong marine-aerosol signal. Instead, the measured PFAS showed little association with sodium, which we used as a tracer of sea spray,鈥� says Persaud.

They did find PFAS at all study sites, but evidence pointed to a break down of PFAS precursor compounds in the atmosphere, which would have been transported from elsewhere and not from sea spray. They mostly found perfluoroalkyl acids (PFAAs), a subclass of PFAS, including perfluoroalkyl carboxylic acids (PFCAs) and perfluoroalkanesulfonic acids (PFSAs), which are not from local sources in Newfoundland.

Instead, these PFAAs likely came from industrial and commercial centres elsewhere in Canada and the United States, and potentially even further afield. PFAAs and their PFAS precursors are typically found in firefighting foams, non-stick materials and performance chemicals and can be transported long distances, including the Arctic, raising environmental and bioaccumulation concerns.

The researchers say their results are not necessarily exclusive to the east coast of Canada either as Newfoundland offers a worst-case scenario in terms of the amount of driving wind, crashing waves and extensive coastline, exacerbating the amount of sea spray and creating the perfect storm for forever chemicals. 鈥淭his sort of sea spray is really not a major source global pollution according to our study,鈥� says Young.

One of the interesting findings pointed to the extent dry depositions contribute to PFAS in the environment. The researchers measured for both wet and dry depositions in this research, but that is not universally done and their results underline the importance of doing so to understand the full impact of PFAS in the environment.

鈥淚t鈥檚 something that hasn't been understood but helps us to better predict where we're going to find forever chemicals when they're moving around the globe and where they will ultimately end up,鈥� says Persaud. 鈥淯nderstanding the difference between wet and dry depositions really helps not only us but other researchers going forward.鈥�

PFAS are not only found in rain and snow, but Young says she still finds it surprising that dry deposition remains so important even in a place like Newfoundland where it rains quite a lot, but it also points to the importance of including dry depositions of PFAS in studies to better understand where they are being deposited, how they are getting there and the environmental impact, whether that鈥檚 a remote desert or the Arctic far from the pollution source.

The 91亚色 researchers worked with scientists at Memorial University in St. John鈥檚, where Young previously worked and collected samples, the Canadian Forest Service, Natural Resources Canada in Corner Brook, and the Aquatic Contaminants Research Division, Environmental and Climate Change Canada in Burlington, ON.

鈥淚 see it as good news story. We worried the PFAS could move from ocean to land and back forever, but it doesn't seem like it's as big of a problem as we thought,鈥� says Young.

The paper, , was published in the Royal Society of Chemistry journal of Environmental Science Processes & Impacts.

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The wiring and rewiring of the brain never ends. Neural pathways are constantly being reshaped as we interact with the world and learn new things. At 91亚色 and MIT鈥檚 McGovern Institute, scientists are combining detailed analysis of brain activity with computational modelling to better understand that change.

91亚色 Assistant Professor , McGovern Institute Postdoctoral Fellow , an affiliate member of Kar鈥檚 lab and a member of the Centre for Integrative and Applied Neuroscience at 91亚色, and Investigator  worked together to compare what happened when monkeys and an artificial neural network with brain-like architecture were trained to visually identify the same objects. As the model鈥檚 performance improved, it reorganized itself in ways that closely paralleled changes the team detected in the brains of monkeys.

Their research, reported  , shows how changes in visual processing support animals鈥� ability to learn to discriminate new kinds of objects. By modelling these changes, the researchers hope to better predict how training reshapes perception, which could one day inform educational strategies for a wide range of learners.

鈥淥ur visual brain does not undergo a drastic reconfiguration when we learn a new object. Instead, it subtly reshapes how visual information is represented, making the distinctions that matter easier for the rest of the brain to read out. What is powerful about this study is that artificial neural networks could predict these subtle brain changes, giving us a concrete bridge between neuroscience and AI,鈥� says Kar. 鈥淏y translating inferences from animal neuroscience into computational models that can generate human-testable predictions, this framework makes translation much more feasible. It allows us to move from understanding how learning changes the macaque visual system to perhaps asking in the near future: why some children may struggle to form stable, generalizable representations 鈥� such as recognizing letters across fonts, linking words to objects, distinguishing faces, or applying knowledge in new situations.鈥�

Subtle changes

Learning about a new object calls on many parts of the brain. Visual-processing areas work together to make sense of information taken in through the eyes, then communicate with other brain areas to give the visual information meaning and guide behavior. Multiple parts of this system likely change during learning, and the research team wanted a clearer understanding of how that change is distributed.

Neuroscientists have debated how much change occurs in the brain鈥檚 visual-processing areas when an animal learns to recognize new objects. Some suspected that visual-processing pathways remain largely unchanged during learning to avoid broadly disrupting visual perception, but others have reported changes in activity within dedicated visual-processing areas with this kind of learning in humans and other primates. 

To take a closer look, the team focused on neural activity in a key component of the brain鈥檚 visual object-processing network, the inferior temporal (IT) cortex. By the time visual information reaches the IT cortex, key object features are clearly represented 鈥� so much so that it鈥檚 possible to 鈥渄ecode鈥� what object a monkey is seeing and even predict what errors it鈥檚 likely to make in identifying it, simply by analyzing patterns of neural activity there.

The team recorded neural activity in the IT cortex from two groups of monkeys as the animals looked at and identified images of objects. Some of the monkeys were untrained, so the images they saw had little meaning to them. Others had already learned to identify similar objects, so they could usually discriminate between elephants, chairs and other select objects, even when those objects were presented at different sizes, from different angles, or against different backgrounds than the ones they had seen before.

The broad pattern of activity in the IT cortex was largely similar in trained and untrained monkeys, suggesting that learning had not dramatically rewritten this high-level visual representation. Still, the group found subtle but reliable differences in the way neurons in the IT cortex responded to images in monkeys that had learned to recognize the kinds of objects they were shown, compared to the untrained monkeys.

Modelling learning

The group turned to computational models to investigate how those modest changes might contribute to learning. S枚rensen trained a suite of artificial neural networks whose internal components had been mapped to monkey IT cortex to identify the same categories of objects the monkeys had seen. The models were designed to learn using gradient descent, meaning they continually improved their accuracy by adjusting their parameters in response to errors.

Only some of the primate-like models showed learning behavior that matched that of the monkeys. In those that did, the IT-like stage changed in ways that resembled the learning-related changes the researchers had observed in the IT cortex of trained monkeys.

While gradient descent is commonly used to train artificial intelligence, it is generally considered biologically implausible as a direct model of how the brain learns. The researchers say the strong match in learning effects between the monkeys and their model demonstrates that these kinds of artificial neural networks can offer insights into biological learning at a useful level of abstraction, even if the brain does not learn in the same way.

鈥淭his shows that you can actually build in silico versions of future experiments,鈥� S枚rensen says. 鈥淚 think that gives us this playground of asking 鈥榳hat if鈥� questions 鈥� and potentially predicting new things that go beyond the experimenter鈥檚 intuition.鈥�

Most of the changes that allowed for learning in the model occurred outside of the IT cortex. 鈥淭his tells us that there is a lot between the area we recorded from and the final behavioral readout that needs to change during this process,鈥� Kar says. He adds that the team鈥檚 model will be useful as researchers look more deeply into how downstream brain areas contribute to learning.

The researchers stress that their study allowed more granular measurements of brain activity than would be possible in humans, and because monkeys鈥� brains are organized similarly to our own, their experiments have direct relevance to human learning. They say understanding the impact of plasticity in monkeys鈥� IT cortex could help researchers design new learning strategies for humans.

鈥淥ur prior conceptual working model of you 鈥� or a monkey 鈥� learning new objects was that your brain makes changes to synaptic connections that are largely downstream of your visual system, so you don鈥檛 destroy your visual system,鈥� says DiCarlo, who is also the Peter de Florez Professor of Brain and Cognitive Sciences and director of the MIT Siegel Family Quest for Intelligence. 鈥淵ou wouldn鈥檛 want your whole visual system to become an elephant detector [just because you鈥檝e learned to identify an elephant]. But this study went beyond that to say actually, when you learn 鈥榚lephant,鈥� your IT does change a little bit to make it a little more relevant to elephants.鈥�

That likely has consequences for recognizing other visual features, too. Subtle changes in the IT cortex that support elephant recognition might also make you better at identifying things other than elephants, DiCarlo says. Likewise, the same changes might make it a little harder to identify something else.

These kinds of consequences may be difficult to predict intuitively, but become obvious with computational modelling. For instance, the team鈥檚 models revealed that after learning to recognize new objects, the IT cortex contained more information about objects鈥� locations. By providing insights like these, models could aid the design of more effective training strategies for visual tasks, including for people with altered sensory processing, who may learn from visual information in atypical ways.

With files from MIT's McGovern Institute

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91亚色 is poised to welcome 11 doctoral students and postdoctoral researchers through the first wave of the federal (CIRTA) initiative, reflecting the University鈥檚 strong research excellence and ability to attract top international research talent.

In total the CIRTA are worth $1.4 million in funding 鈥� $40,000 per year for three years for seven doctoral students and $70,000 for two years for four postdoctoral researchers at 91亚色 鈥� to address critical national and global challenges in some of Canada鈥檚 priority areas. Altogether, the CIRTA will go towards funding 600 doctoral students and 400 postdoctoral researchers at universities across Canada.

"We are thrilled to welcome these 11 exceptional doctoral students and postdoctoral researchers to 91亚色. They will bring an array of international experiences and perspectives to their work alongside some of our most accomplished faculty, researchers whose expertise spans multiple disciplines, methodologies, and questions. It is the strength of these mentors and the vibrancy of our research community that draws top talent from around the world to 91亚色,鈥� says Lisa Philipps, 91亚色 interim president and vice-chancellor.

The recently CIRTA results are part of the a $1.7 billion strategy to strengthen the country鈥檚 position as a go-to-place for the world鈥檚 top scientists and innovators. They are jointly administered by the Canadian Institutes of Health Research (CIHR), the Natural Sciences and Engineering Research Council of Canada (NSERC), and the Social Sciences and Humanities Research Council (SSHRC).

91亚色 received a large number of highly qualified candidates for the positions, which will receive funding from all three funding agencies. In addition, two of the four postdoctoral researchers are coming from the social sciences and humanities.

鈥淲e are equally grateful to the Government of Canada and to CIHR, NSERC and SSHRC, whose Canada Impact+ Research Training Awards make these opportunities possible. This kind of bold public investment in emerging academic talent is exactly what strengthens our research culture and allows ambitious ideas to take root. Together, the vision of our funders and the dedication of our scholars and supervisors will help tackle some of the most pressing challenges of our time, from removing forever chemicals from our water to strengthening our preparedness against emerging diseases. I could not be prouder of what this community will achieve,鈥� says Philipps.

The CIRTA research awards target specific high priority research needs identified by the federal government across disciplines.

At 91亚色 the doctoral students and postdoctoral researchers and their supervisors will embark on a vast array of research, including a climate-sensitive disease early-warning system, advanced functional materials for low-energy carbon capture, AI forecasting tools to improve outbreak prediction and public-health decision-making, methods to remove forever chemical contamination from wastewater sludge, and a better understanding of new drivers of aging and development of new personalized therapies to improve health span.

鈥淩esearch thrives when talented people are given the opportunity, support and freedom to pursue ambitious ideas. These scholars are asking important questions and bringing fresh perspectives to issues that matter deeply to society. Their arrival enriches our academic community, and we look forward to the contributions they will make during their time at 91亚色 and throughout their careers,鈥� says Alice MacLachlan, vice-provost and dean of the Faculty of Graduate Studies at 91亚色.

The following 91亚色 faculty members welcome doctoral students funded by the program:

Associate Professor and Canada Research Chair in Global Health and Humanitarianism Godfred Boateng, School of Global Health, Faculty of Health (supported by SSHRC)

Boateng鈥檚 research interests lie in resource insecurity, health and sustainable livelihoods; environmental pollution, climate change and health effects; the socio-ecological determinants of cardiometabolic conditions in aging adults; health equity and health systems research; and implementation and scale-up science in low- and middle-income countries. The research of his doctoral student will focus on the development a climate-sensitive disease early-warning system for informal settlements in Accra, using satellite data, health records, and machine learning to predict emerging disease hotspots. By co-designing tools with local health workers and communities, the project aims to enable earlier public-health interventions and create a scalable model for climate-health resilience in rapidly urbanizing cities.

Associate Professor , Department of Mechanical Engineering, Lassonde School of Engineering (supported by NSERC)

Freire-Gormaly鈥檚 research focuses on the development of stand-alone solar powered reverse osmosis water treatment systems and energy recovery systems for remote communities that lack access to grid electricity. She also is interested in machine learning applications for smart design of innovative energy and water systems. The research of her doctoral student will foster the development advanced functional materials for low-energy carbon capture and drinking water treatment, with a focus on modular, affordable systems that can operate in remote and resource-constrained settings. By combining materials innovation, computational modelling, and life-cycle assessment, the project aims to deliver scalable clean technologies that support climate mitigation, water security, and community resilience.

Associate Professor , Department of Electrical Engineering & Computer Science, Lassonde School of Engineering (supported by NSERC)

Ghafar-Zadeh鈥檚 research focuses on microelectronic and biosensing technologies for clinical diagnostics and environmental monitoring to address critical challenges in health care, environmental monitoring and scientific research through his Biologically Inspired Sensor and Actuator Laboratory. The research with the doctoral student will develop a new version of DePerio, an AI-powered saliva screening tool that uses deep learning to detect oral neutrophils as biomarkers of periodontal disease and potential neurological disorders, enabling earlier, non-invasive diagnosis. Building on proof-of-concept results achieving 88 per cent precision and 94.7 per cent mAP, the project aims to validate a clinically deployable system that links oral inflammation to disease progression and improves preventive care for both oral and brain health.

Associate Professor , Department of Social Science, Faculty of Liberal Arts and Professional Studies (supported by SSHRC)

Hamraie鈥檚 doctoral student will be part of 91亚色鈥檚 Science and Technology Studies graduate program. His research will address the tensions between approaches to accessibility based in mass standardization and those that are rooted in disability activism. In particular, he is interested in how disability activists and technologists have shared information, theories and concepts, and how accessible computing, in particular, has influenced architectural practice. As a graduate student, he will also continue to work in Hamraie鈥檚 , a collective of disabled artists, designers and researchers who approach accessibility through disability cultural frameworks. 

Professor , Department of Earth & Space Science & Engineering, Lassonde School of Engineering (supported by NSERC)

Hu鈥檚 research focuses on developing scalable and interpretable AI approaches for forest characterization, carbon estimation, biodiversity assessment and environmental monitoring using multi-source remote sensing data. Her doctoral student鈥檚 research will develop multimodal AI techniques that combine LiDAR, multispectral imagery and forest inventory data to identify individual tree species in Ontario鈥檚 mixed and transitional forests. By enabling scalable species-level forest monitoring, the project will improve biodiversity assessment, forest carbon quantification, and evidence-based forest management to support nature-based climate solutions in Canada.

Professor and 91亚色 Research Chair in Mechanisms of Cardiometabolic Disease Gary Sweeney, Department of Biology, Faculty of Science (supported by CHIR)

Sweeney鈥檚 doctoral student鈥檚 research will build on evidence that high adiponectin levels are linked to exceptional longevity and protection against age-related diseases, while low levels are associated with poorer health outcomes. It proposes combining adiponectin biology with extracellular vesicle science to identify new drivers of aging and develop personalized therapies to improve health span in individuals with low adiponectin.

Associate Professor , Department of Electrical Engineering & Computer Science, Lassonde School of Engineering (supported by NSERC)

Tabassum鈥檚 research focuses on developing trustworthy AI for wireless sensing, localization, spectrum intelligence, and next-generation communications. Her work combines optimization, machine learning, large language models, and multimodal AI to advance intelligent resource management, integrated sensing and communications, wireless forecasting, and energy-efficient 5G/6G networks, with applications in digital health, smart infrastructure, and connected and autonomous systems. The research of her doctoral student will develop multimodal AI techniques for wireless localization and spectrum intelligence by combining radio-frequency measurements with complementary sensing modalities to enable accurate positioning and automated understanding of complex wireless environments. By integrating trustworthy AI, deep learning, and large language models, the project aims to improve spectrum awareness, network intelligence, and wireless resilience, supporting the deployment of next generation 5G/6G systems for smart infrastructure, public safety, and autonomous applications.

The following faculty members will welcome postdoctoral researchers funded by the program:

Professor and James and Joanne Love Chair in Environmental Engineering and Director of the One WATER Institute , Department of Civil Engineering, Lassonde School of Engineering (supported by NSERC)

Brar is a globally recognized researcher with expertise in value-added waste processing through the development of bioproducts from wastewaters and sludge using fermentation technologies and the removal of emerging contaminants, such as microplastics and pharmaceuticals. She also works on innovative treatment technologies for environmental remediation. The postdoctoral researcher鈥檚 work will address the wastewater sludge contamination of per- and poly-fluoroalkyl substances (PFAS), a group of 4,700 man-made 鈥渇orever chemicals鈥� found in non-stick cookware, cosmetics and waterproof textiles, and everywhere from groundwater to human blood. Current wastewater treatment plants were not designed to primarily remove PFAS, however, if they are not properly treated prior to discharge, it can lead to contamination of soil and groundwater. Conventional PFAS removal methods like sludge pyrolysis, incineration, electrochemical oxidation are energy and cost intensive and cannot be easily integrated into existing plants. Through their research, Brar and her postdoctoral researcher will develop a circular-economy pretreatment approach using ultrasonication and biochar to reduce 鈥渇orever chemicals鈥� while enhancing biogas production. Through lab and pilot-scale testing on anaerobic digester sludge, the research aims to optimize conditions for PFAS removal in a way that is compatible with existing treatment infrastructure.

Associate Professor , Department of Sociology, Faculty of Liberal Arts and Professional Studies (supported by SSHRC)

Jean-Pierre鈥檚 research in the sociology of education, sociology of race and ethnicity, youth studies, and research methodology. She focuses on school and postsecondary trajectories, policies and interventions, and qualitative research. The research of her postdoctoral researcher will redefine democracy as every day, community-based practice by examining how Black women in Brazil, Argentina, and Canada build collective infrastructures of care, mutual aid, and political organizing amid systemic exclusion and democratic crisis. Through comparative ethnography, it shows how these grassroots practices sustain and reimagine democratic life beyond formal state institutions, challenging dominant models shaped by anti-Blackness and inequality.

Professor and Scientific Director of the Artificial Intelligence for Public Health Advancement Seyed Moghadas, Department of Mathematics and Statistics, Faculty of Science (supported by NSERC)

Moghadas鈥檚 research involves advanced theoretical and computational methods for modelling and analysis of infectious disease dynamics, evaluating public health interventions and policies, and health economics of healthcare programs. The postdoctoral researcher will develop transparent, uncertainty-aware AI forecasting tools that combine machine learning with mechanistic disease-transmission models to improve outbreak prediction and public-health decision-making. By integrating diverse data sources and explicitly quantifying uncertainty, the project aims to strengthen preparedness, resource allocation, and health system resilience against emerging infectious disease threats.

Associate Professor and Canada Research Chair in Social Reasoning , Department of Philosophy, Faculty of Liberal Arts and Professional Studies (supported by SSHRC)

Rini is an internationally recognized expert in the philosophical disciplines of ethics and epistemology. In ethics, she specifically examines structural injustice and the complexities of moral disagreement, while in epistemology, she has studied the effects of online misinformation on public debate and the erosion of digital recording as a regulator of testimony. Rini will supervise a postdoctoral researcher examining how testimonial narratives in the Colombian and Canadian truth commissions contribute to reparative justice by helping survivors reclaim agency, foster collective understanding and rebuild social trust after systemic violence. Through a comparative philosophical analysis, the project develops a framework for understanding narrative as a tool for epistemic repair and reconciliation while exploring its limitations in addressing ongoing structural inequalities. The research will look at the following three questions: The guiding questions are: What is the relationship between testimonial narrative and reparative justice; How does narrative support individual healing, collective recognition and the rebuilding of social trust; and What tensions arise between individualized testimonies and structural accounts of systemic injustice?

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TORONTO, June 4, 2026 鈥� A team led by 91亚色 researchers has discovered the fastest wind near a supermassive black鈥痟ole鈥痚ver鈥痜ound at ultraviolet wavelengths, driven by鈥痶he disc of matter, or quasar, surrounding the black hole.鈥�&苍产蝉辫;

鈥淭his quasar has a black hole of 1.7鈥痓illion鈥痶imes鈥痶he mass of the Sun. That鈥檚 typical. What鈥檚 not typical is that it has gas moving towards us at 30 per cent of the speed of light,鈥� says of the Faculty of Science.鈥���&苍产蝉辫;

The , published by The American Astronomical Society.鈥�&苍产蝉辫;

The research team includes 91亚色 graduate student and lead author Lucas Seaton, graduate student Marianna Veltri, and undergraduate student Zezhou Zhu, along with colleagues from the University of Washington Bothell and other members of the Sloan Digital Sky Survey (SDSS) collaboration.  

鈥淭his quasar, known as J2318 (Jay Twenty-Three Eighteen), can be found in the Great Square in the constellation of Pegasus,鈥� says Seaton. 鈥淚n terms of its speed, this quasar鈥檚 wind could be called a category 79 hurricane,鈥� says Seaton. 鈥淓very category of hurricane is about 20 per cent faster than the category below it. Calling it category 79 gives an idea of just how fast it is, but of course this wind is unlike anything on Earth.鈥濃��&苍产蝉辫; 

Astronomers have known for close to three decades that every large galaxy has a supermassive black hole at its centre, with a mass from millions to billions of times that of the Sun, although contrary to popular belief they do not eat everything in reach. Matter spiraling into one of these black holes forms a disc far bigger than Earth鈥檚 orbit around the Sun and hotter than the surface of the Sun. These discs of hot gas, called quasars, generate enough light to be seen across the observable universe and to drive winds from their surfaces.  

鈥淚n quasars, we often see winds of gas pushed away from the black hole by the light of the quasar,鈥� says Seaton. 鈥淭he wind in J2318 can be seen at ultraviolet wavelengths at velocities up to 30 per cent the speed of light. Even faster winds can be seen at x-ray wavelengths, but J2318 is the fastest ever discovered at ultraviolet wavelengths.鈥�  

Unlike the differences in gas pressure that drive atmospheric winds on Earth, winds from quasars are pushed at least in part by light itself. Individual packets of light (called photons) bounce off or are absorbed by atoms in the gas and accelerate them.   

鈥淨uasars put out so many photons that those tiny pushes add up to extreme velocities,鈥� says Seaton. 鈥淭he problem is, the photons can also remove all the electrons from the atoms, making them invisible. How to push the gas to the speeds we see while keeping the carbon and silicon ions we see intact鈥� it鈥檚 quite a puzzle.鈥�  

The discovery relied on data from two components of the SDSS, an international survey of the night sky to which hundreds of astronomers have contributed since its start in 1998, specifically, the SDSS-IV and the SDSS-V . Veltri flagged the quasar as potentially interesting in SDSS-V in 2023 while an undergrad student at 91亚色. After looking at it using software set up by Zhu, Hall realized it had an extremely fast wind.  

鈥淐anada has a share of the eight-meter-diameter  (also known as Gemini North) in Hawai鈥檌, and we immediately proposed observations with it. They succeeded in confirming its record-breaking wind velocity,鈥� he says, adding that he often involves 91亚色 undergraduates in research as part of his participation in the SDSS.鈥�&苍产蝉辫; 

He explains that 鈥渏ust as a rainbow spreads the Sun鈥檚 light into different wavelengths (colours), the SDSS spreads out the light from certain stars, galaxies, and quasars into what we call their 鈥榮pectra鈥�. From those spectra, with practice, students learn to spot unusual quasars. In the past, only PhD astronomers or graduate students studying for a PhD would have made a discovery like this, but the SDSS enables undergraduates to do so.鈥�  

Study co-author, Associate Professor Paola Rodr铆guez Hidalgo of the University of Washington at Bothell, adds: 鈥淏oth Patrick and I have been working together and with undergraduate students thanks to the SDSS Faculty and Students Team (FAST) initiative that supports these collaborations. Initiatives like this allow students to focus on research while finishing their undergraduate studies. These students will be the next generation of scientists and are already making scientific discoveries.鈥�  

Co-author Liliana Flores, who worked with Professor Rodr铆guez Hidalgo as an undergraduate at UW Bothell and was a FAST participant, says she was thrilled to contribute to the study of this extreme outflow case. 鈥淚 was in charge of fitting the absorption profiles in the quasar spectrum to determine their velocity and equivalent widths. Repeated observations revealed that the amount of absorbed light changes over time. Something in the wind conditions must be changing for that to happen.鈥濃��&苍产蝉辫; 

Veltri assembled measurements of the brightness of the quasar from 20 years of surveys, starting with the original SDSS. That data shows that J2318 is slowly varying in brightness in a way indistinguishable from other quasars. Only by taking detailed measurements of spectra with SDSS was the wind in J2318 revealed.  

Rodr铆guez Hidalgo calls the discovery exciting. 鈥淭hese extreme outflows carry incredible amounts of energy that can affect the galaxies around them. They serve as a sort of missing link: the elusive feedback between the active central region of a galaxy and the rest of the galaxy. While this process has been included in simulations of galaxy formation for decades, a lot more work needs to be done to understand it from observations and make sure the simulations handle it correctly.鈥�  

Searches are continuing for more extremely high velocity outflows from quasars, says Flores. 鈥淚t won鈥檛 be easy to find a faster ultraviolet outflow than that of J2318, but we are continuing this search from the nearby universe to the most distant reaches of the universe that we can see.鈥� 

Joint with:鈥�&苍产蝉辫;
Sloan Digital Sky Survey鈥�&苍产蝉辫;
University of Washington Bothell鈥�&苍产蝉辫;
The Pennsylvania State University (local only)鈥�&苍产蝉辫;

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The new Centre of Excellence will bring together multiple disciplines across the University to develop and deploy artificial intelligence systems to improve health care

TORONTO, April 9, 2026 鈥� As artificial intelligence (AI) becomes increasingly important, especially in the health-care field, 91亚色 continues to play an outsized role. Today, the University announced the launch of a new Centre of Excellence 鈥� Artificial Intelligence for Public Health Advancement (AIPHA) funded through an Ontario Research Fund 鈥� Research Excellence program.

Director General, Applied Public Health Sciences Pamela Ponic of the Science and Policy Integration Branch, Public Health Agency of Canada, Chief Medical Officer of Health for the Ontario Ministry of Health Kieran Moore, and MPP for Whitby Lorne Coe, Parliamentary Assistant to the Minister of Colleges, Universities, Research Excellence and Security all spoke at the lunch-time event.

As a key player in supporting health-care decision making, AIPHA will strengthen external partnerships and accelerate the transfer of knowledge from research to policy and practice, where hospitals, medical practitioners, policymakers and leaders can use it. It will also help bridge the gap between health analytics and real-world socioeconomic conditions further positioning 91亚色 as a national and global leader in AI-integrated public health solutions through research and innovation.

"The launch of AIPHA marks a defining moment for 91亚色 and for the future of public health in Canada. By bringing together expertise across disciplines, from mathematical modelling and AI to health policy and social equity, we are creating something truly transformative: a hub where research doesn't just advance knowledge but directly shapes the decisions that protect and improve people's lives,鈥� says 91亚色 Interim President and Vice-Chancellor Lisa Philipps. 鈥�91亚色 has long been committed to addressing society's most pressing challenges, and AIPHA reflects that mission at its fullest. We are proud to be building the next generation of AI-adept public health leaders right here, and to be positioning Canada as a global force in equitable, evidence-informed health innovation."

As a dedicated, multi-disciplinary and national hub, AIPHA will bring together expertise from across faculties, including in advanced mathematical and computational modelling, precision analytics and multi-source databases. The goal is to integrate epidemiological, clinical, environmental, climate and socioeconomic indicators in newly created AI models, while training the next generation.

鈥淎rtificial intelligence tools are increasingly being used in health-care settings but a coordinated, ethical and equitable approach to ensure the tools use integrated data sources, and that they are being properly tested and deployed for patient good is lacking. The current speed of newly developed AI models is at times outpacing governance,鈥� says Faculty of Science Dean Maydianne Andrade. 鈥淎s a new Centre of Excellence in the Faculty of Science, AIPHA will lead the way toward better integration of these new technologies in a cohesive manner that will help advance public health care.鈥�

Two projects already underway include: Integrating AI with disease transmission dynamics models for informed prevention and control of outbreaks in indoor and mass gathering settings (2025 to 2031) and Advanced mathematical technologies for respiratory infection risk assessment and pharmaceutical intervention scenario analysis (2024 to 2028), both led by AIPHA鈥檚 inaugural director Jianhong Wu.

鈥淭he AI for Public Health Research Centre is a coordinated innovation hub that will help improve health-care efficiency and outcomes, as well as ensure coordinated, ethical and equitable transformation of public health systems,鈥� says AIPHA Director and University Distinguished Research Professor Jianhong Wu of the Faculty of Science. 鈥淭his kind of central hub is much needed in the health-care sector today to ensure emerging AI tools are properly integrated and decision and policy makers are provided with robust information toward developing a more cohesive, ethical and equitable public health-care system.鈥�

AIPHA will integrate epidemiological, clinical, environmental and socioeconomic data into the AI-enabled decision-support systems it develops and deploys to guide equitable and evidence-informed public health action. In ensuring the development of fair and equitable AI systems, the hub will combine not only advanced mathematical and computational modelling and AI and predictive analytics, but also health systems and policy research with social determinants of health and equity frameworks.

AIPHA will act as a research accelerator for large collaborative grants, train the next generation of AI-adept public health leaders and develop pilot AI-integrated protypes for infectious disease modelling, health system resource allocation and climate health risk forecasting.

It will also strengthen Canadian pandemic and emergency preparedness, enhance evidence-based policymaking, support climate-health adaptation strategies, improve health equity outcomes, and increase 91亚色鈥檚 national visibility in AI governance and public health innovation.

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At this point, Avian flu H5N1 is thought to have very limited ability to transmit between humans, but a recent case in British Columbia with an unknown source of transmission has piqued the curiosity and concern of scientists, including 91亚色 Professor Seyed Moghadas.

Did this lone case come about through transmission from an animal or another person, and if it was via human transmission, what methods will control its spread in the human population? Director of 91亚色鈥檚 Agent-Based Modelling Laboratory in the Centre of Excellence in AI for Public Health Advancement, Moghadas and a group of researchers used modelling to understand the best spread control measures should human-to-human transmission become possible.

鈥淭he idea was, let's evaluate some of the interventions that we usually implement at the very earliest stage of a disease outbreak or emerging disease, which we know very little about,鈥� he says.

For the research, ",鈥� published today in Nature Health, various scenarios from isolation to vaccination before or after a spillover event were modelled. It is one of only a few studies that have explicitly modelled outbreak dynamics following spillover into humans or the effectiveness of public health interventions in early and highly uncertain phases of virus development.

As a professor of computational epidemiology and vaccine science in 91亚色鈥檚 Faculty of Science, Moghadas and his colleagues were already collecting data on H5N1 cases in the United States when the Canadian case arose. Given the unknown nature of transmission, the team decided to pivot their work to look at what was happening in B.C.

鈥淭he case in B.C. was of particular interest for us because no definitive source of exposure was identified, including no direct contact with infected animals or known high-risk settings such as poultry farms,鈥� says Moghadas. 鈥淏ecause of that, it came to our attention that maybe there is some sort of transmission going on between humans.鈥�

As far as health and science experts know, H5N1 can only be transmitted among poultry and dairy cattle on farms, as well as through wild birds, and from these animals to humans, but sustained human-to-human transmission has not been established. The person from B.C., however, had no clearly identified exposure and even though human infection from animals is rare, avian influenza H5N1 is considered highly pathogenic and a potentially serious and evolving threat to global public health.

鈥淭his virus was first identified in 1997 in Southeast Asia. This kind of zoonotic virus essentially jumps from the bird or animal side to human side sometimes, mostly it circulates among wild birds,鈥� says Moghadas. 鈥淭here is no confirmation that human-to-human transmission happens as yet in North America.鈥�

The virus has only been in North America since 2022, but surveillance monitoring for it began in 2003 and up until recently there have been close to 1,000 cases reported globally in humans and just under 500 deaths, although the number of cases could be higher because not all cases are likely reported or symptomatic. The virus has not only expanded its geographical range, but also the animal species it can infect.

鈥淓volution of influenza viruses of any type is always a challenge for humans. The flu virus is one of the very rapid mutating pathogens,鈥� he says. The concern is it will mutate to be able to transmit between humans. How viable is it? How easily can it spillover from animals to humans, and how long could the potential chain of transmission from human-to-human become? These are still open questions.

鈥淨uantifying that risk was important for us because that could also give us direction in terms of how bad the disease could be and what strategies will work to contain it,鈥� says Moghadas. 鈥淲e have very few measures in place or a strategy to deal with it at this point, given that the transmission between humans is not established.鈥�

As it is an avian flu virus, it will likely require two doses of a similar vaccine to what was used during the H1N1 pandemic to reduce the risk and severity which often triggers a higher viral load.

The researchers used Abbottsford, B.C. as the location as it is a highly dense poultry farming area. The starting point is after a spillover has happened. 鈥淚f a human became infected, how do we block this single individual to trigger a large outbreak? Or if the infection is going on between humans, can we block these chains and to what degree we can block them?鈥� asks Moghadas. 鈥淲hat is the effectiveness of either self-isolation of symptomatic cases or vaccination of farmers or vaccination of farmers and their household members?鈥�

Even with mitigation measures, someone in the farmer鈥檚 family could potentially be infected by the farmer and then transmit it to someone in the community.

The team evaluated two different types of vaccination strategies. One was reactive, which means that you trigger a vaccination program after a case has been identified somewhere. The second strategy was pre-emptive 鈥� individuals, such as farmers, are vaccinated before any case is identified.

What they found is that reactive vaccination has very limited additional benefits outside of self-isolation, but pre-emptive vaccination adds substantial additional benefits on top of self-isolation.

Should the virus be confirmed to be capable of human-to-human transmission, Moghadas says they want to limit the chain of transmission and minimize the risk of evolution of the virus to become more adapted to human conditions. For now, he says, when cases are identified, the person should self isolate immediately. For the authorized vaccine, it should be meted out quickly to target populations, but that could take several weeks to have population level effectiveness.

鈥淭imely action is a critical part of controlling the spread. Self-isolation of symptomatic cases has a significant effect, but that comes with the caveat that we don't know if everybody who is infected will develop symptoms,鈥� says Moghadas. 鈥淭here could be potential asymptomatic cases we don't identify and by the time we do identify them, they've been already infecting others in the chain of transmission. This case in B.C. was particularly concerning because they could not find the source of infection.鈥�

The concern is not only that the virus might be able to jump from animals to humans, but also the potential for it to mutate during early human transmission chains making it more adaptable to infecting humans. This underscores the risk of local outbreaks with global implications, he says.

鈥淢y research is all about evidence generation for governments, health-care providers and policymakers in public health organizations. We are generating evidence that can be used to at the very least limit the potential for this virus to become another pandemic,鈥� says Moghadas.

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Tiny sliver of Crescent Moon and Venus will also conjunct on first day of spring

TORONTO, March. 17, 2026 鈥� While it may not currently feel like it in parts of the country, this coming Friday marks the first day of spring, known astronomically as Spring Equinox, and this will also bring an increased chance of Aurora viewing in Canada.

鈥淭his March 20 the magnetic fields of the Sun and the Earth work in conjunction with geometry to give us a good chance at Aurora, so fingers crossed for some solar activity,鈥� says 91亚色 Faculty of Science Associate Professor , director of the Allan I. Carswell Observatory at 91亚色.

The Equinox is often described as 'equal day' and 'equal night' but in fact it is just near to when the day and night are most equal for your location, she explains. At higher latitudes the inequality between the lengths of our days and nights grows. The Equinox could be described as the time when Earth is most evenly facing the Sun. 

That in itself is a bit of a trick, says Hyde, as Earth's axis is tilted about 23.5 degrees away from the plane of the solar system. So, if you imagine the Sun, the Earth and the planets all in a line, Earth would be orbiting the Sun tilted just a bit away or towards it depending on where it is in the orbit. This leads to the seasons and at the Equinox the Earth's magnetic poles are tilted nearly at a right angle to the flow of solar wind from our Sun two times a day. This 'equinoctial effect' presents a bigger target for charged particles to hit. 

鈥淎s the seasons change to Summer or Winter, the poles point either more toward or away from the Sun, reducing this effect,鈥� says Hyde. 

This same alignment near the Equinox also means that the magnetic fields of the Earth and Sun can line up in a way that could allow them to connect. 

鈥淭his is when the 'north-south' of Earth's magnetic field is opposite the Sun's, and opposites attract in magnets,鈥� says Hyde. 鈥淭his is called the Russel-McPherron effect and together the two effects can lead to more frequent and brighter auroras when the Sun is active.鈥�

The Sun is currently in the most intense phase of its 11-year cycle, moving from minimum to maximum activity or vice-versa. In general, near the maximum we always see more solar activity, but there is also an increase near the Equinox to look forward to.聽

As an extra astronomy bonus, with the New Moon on March 19, we also have a conjunction between a very faint sliver of a Crescent Moon and the planet Venus this Friday. In Ontario this will occur near sunset in the West, low on the horizon, so observers with a clear view in that direction will get an extra treat.

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91亚色 is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change, and prepare our students for meaningful life and career paths. 91亚色's Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91亚色鈥檚 campus in Costa Rica offers students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future.

Media Contact: Emina Gamulin, 91亚色 Media Relations, 437-217-6362, egamulin@yorku.ca

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91亚色 U led study found clear vaccine-initiated immune response biomarkers between HIV positive and HIV negative groups, but outliers underscore varied, intricate nature of the immune system

How people with compromised immune systems respond to vaccines is an important area of immunological research. A led by 91亚色 found that not only could machine-learning models accurately pinpoint differences in healthy controls and those living with HIV, but also found outliers in both groups that provide fascinating glimpses into the complex nature of the immune system and what personalized medicine could look like in the future, accounting for variables such as age, comorbidities and genetics.

鈥淭his study constitutes an important step forward in the potential for personal vaccination intervention strategies,鈥� says lead author Chapin Korosec, who worked on this paper as a postdoctoral fellow at 91亚色 under the supervision of Faculty of Science Professor , whose research focuses on infectious disease modelling. 鈥淏y learning the structure of immune variability at scale, we move toward a data-driven foundation for personalized vaccination and therapeutic design.鈥�

Korosec, now an adjunct professor with the University of Guelph, used a dataset of people with and without HIV who had received up to five doses of COVID-19 vaccine over the course of 100 weeks. All the individuals living with HIV were from the Greater Toronto Area whose illness was being controlled with antiretroviral therapy. The researchers used a type of machine-learning method called random forest to analyze 64 immune biomarkers elicited through a response to the COVID-19 vaccine, and then created a group of 鈥榲irtual patients鈥� to further model immune responses.

鈥淲hile we were working with a rich dataset well suited for statistical testing, longitudinal mathematical models still face identifiability limits when the data cannot uniquely resolve immune dynamics. We therefore turned to machine learning to identify the core differences between groups, and then leveraged that learned structure to generate virtual patients that capture how immune patterns differ between groups.鈥�

They were able to show that saliva-based antibodies, particularly a type of antibody in the saliva called IgA, coupled with white blood cells, which have long been known to be associated with HIV status, create the signature difference between the two groups. Korosec says this is significant because there is a lot of research showing altered mucosal immunity for those living with HIV and how it is influenced in the short and long term.

Heffernan notes that they identified subgroups within the HIV positive group, which highlights the importance of personalized vaccination strategies and the challenges of modelling immune responses due to individual variability.

鈥淭he immune response is very, very complicated.鈥� explains Heffernan. 鈥淪ometimes something can act as an inhibitor of an arm of the immune response, but in other times it might be an activator. There is also a lot of individual variability among people with similar immune system status. Using machine learning, mechanistic modelling, and 鈥榲irtual patients鈥� we can try to uncover important differences in the subgroups and between individuals 鈥� even of immune system components that are not measured in the data. Kind of like trying to find the needle in a haystack, but with a clearer path to finding it.鈥�

The HIV positive group, despite having the benefits of antiretroviral therapy, had clear differences in their vaccine-elicited responses compared to the control group and the machine-learning model was able to classify those differences with nearly 100 per cent accuracy, but there were two individuals who they could not differentiate from the control group.

鈥淣o matter how we shuffled the data or which biomarkers we used, the machine-learning algorithm could not distinguish a small subset of HIV-positive individuals from those who were HIV-negative,鈥� says Korosec. 鈥淚n those individuals, the vaccine-induced immune responses were indistinguishable from the HIV-negative group. That suggests that, at least in terms of vaccination response, their immune function was effectively restored.鈥�

Conversely, there was one individual in the healthy control group whose markers looked indistinguishable from someone living with HIV, which may suggest underlying immune issues that may not yet have been clinically identified.

Supported by the National Research Council of Canada (NRC)-Fields Mathematical Sciences Collaboration Centre, the National Sciences and Engineering and Research Council of Canada and Artificial Intelligence for Public Health (AI4PH), the study was published today as a pre-print in the Journal Patterns and will appear in print as the cover article on March 13. Korosec worked with collaborators, including Heffernan,  Senior Research Officer Mohammad Sajjad Ghaemi from the NRC Digital Technologies Research Centre, Associate Professor Jessica Conway from Pennsylvania State University and researchers from the University of Toronto and St. Michael鈥檚 Hospital.

鈥淭his study moves us closer to understanding immune diversity in people living with HIV; how their responses compare to age-matched controls, how well antibodies are maintained over time, and why some individuals show strikingly different patterns,鈥� says Korosec.

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91亚色 is a modern, multi-campus, urban university located in Toronto, Ontario. Backed by a diverse group of students, faculty, staff, alumni and partners, we bring a uniquely global perspective to help solve societal challenges, drive positive change, and prepare our students for meaningful life and career paths. 91亚色's Glendon Campus is home to Southern Ontario's Centre of Excellence for French Language and Bilingual Postsecondary Education. 91亚色鈥檚 campus in Costa Rica offers students exceptional transnational learning opportunities and innovative programs. Together, we can make things right for our communities, our planet, and our future.

Media Contact: Emina Gamulin, 91亚色 Media Relations, 437-217-6362, egamulin@yorku.ca

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91亚色 researchers say the decrease in the smallest PFAS during COVID points to its sources and the potential to change the environmental levels of it in the future

TORONTO, Jan. 29, 2026 鈥� A new study out of 91亚色 has found that the amount of atmospheric trifluoroacetic acid (TFA), the tiniest forever chemical, significantly declined in Toronto during COVID in 2020, which researchers say is good news for the world鈥檚 ability to mitigate it in the future.

鈥淲hen we turned off the tap, so to speak, and we all went home and stopped normal activities, we saw a really quick response, a dramatic reduction of TFA. But the real surprise is that the results point to TFA being formed from short-lived chemical precursors emitted into the atmosphere,鈥� says 91亚色 atmospheric chemist Professor Cora Young, senior author of the paper published today. 鈥淚 was so surprised when we saw that it had decreased during the pandemic, but I had to double and triple check the data because I didn鈥檛 believe it at first.鈥�

The reason it is such good news, says Young is 鈥渢hat when there is an immediate response after emissions reduction, it tells us that we should be able to figure out how to minimize the emissions and control the formation of TFA in the future. We could have a lot more control over this than we previously thought and that鈥檚 very exciting. If we don't know where it's coming from, it's very difficult for us to regulate.鈥�

Unfortunately, as people returned to work and daily life, these levels have crept back up and they peak in the summer when there is more light, which is needed for its creation. A short-chain per- and polyfluoroalkyl substance (PFAS), TFA forms in the atmosphere when various chemical emissions come together.

鈥淭FA is something that we haven't known a lot about before, but we're learning more now that we can measure it,鈥� says 91亚色 PhD Candidate Daniel Persaud, the paper鈥檚 lead author. 鈥淲ith levels of TFA dropping during the pandemic, it now gives us a lot more information about its thousands of sources, such as industrial and vehicle air conditioner emissions.鈥�

The researchers collected and analyzed monthly measurements of both wet (rain and snow) and dry deposition 鈥� gases and particles that land on surfaces and form a layer of dust, for example, on windows and car windshields 鈥� from the Air Quality Research Station on roof of 91亚色鈥檚 Petrie Science and Engineering Building between 2018 to 2024.

What is still unknown, is the effect of long-term exposure on people and wildlife. Young says TFAs are already orders of magnitude higher in the environment than some of the other PFAS, such as perfluorooctanoic acid, known as PFOA. PFOA was the subject of successful lawsuits with hundreds of millions in payouts, including from DuPont, which is also the focus of the 2019 documentary Dark Waters.

鈥淭he short-chain PFAS precursors were supposed to be more benign, and many are, but not all and so that created more unknowns about their effect. There is preliminary evidence that is behaving in ways we didn't expect. We鈥檙e finding it at high concentrations in food, for example,鈥� says Young of 91亚色 Faculty of Science.

鈥淲e didn鈥檛 think that PFASs like TFA could bioaccumulate, but they鈥檝e been found to accumulate in plants, and can be found in the food people and wildlife eat. It has even been found in human blood. Our exposure could still be quite high, even if it's not bioaccumulating. If TFA levels in the environment are driven by short-lived emissions, then that鈥檚 something we can actually address now.鈥�

A little history

The main precursor chemicals that form short-chain PFASs are the second generation of chemicals designed to replace the ozone-depleting chlorofluorocarbons (CFCs), phased out globally starting with the 1987 Montreal Protocol. These first-generation replacement chemicals remain for years to decades in the atmosphere and can slowly react to form short-chain, persistent PFAS, like TFA, thought to be better than CFCs at the time, but these forever chemicals are now found everywhere from the Arctic to the Antarctic and there is no way to turn back the clock on them.

鈥淭he change from long-lived to short-lived precursors was made for climate reasons because the long-lived ones are also really potent greenhouse gases,鈥� says Persaud of the Faculty of Science. 鈥淲e previously though the biggest source of TFA was first-generation CFC replacements, but our results show the important role of short-lived, next-generation replacements.鈥�

An example of that change is that in North America all car air conditioners from 2019 onwards now use a short-lived TFA precursor rather than the long-lived PFAS precursors. However, if these performance chemicals for air conditioners are finding their way into the atmosphere, it鈥檚 expensive for car manufacturers and consumers for alike.

The paper, , was published in journal Environmental Science & Technology Letters.

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