Plastic particles increase inflammation and cross barriers

Lukas Kenner, visiting professor, Department of Molecular Biology.
Photo Credit: Medizinische Universität Wien

Scientific Frontline: "At a Glance" Summary

• Core Discovery: Micro- and nanoplastics (MNPs) exacerbate chronic inflammatory bowel diseases (IBD) and penetrate biological barriers to accumulate in vital organs beyond the gastrointestinal tract.
• Methodology: Researchers utilized a mouse model of ulcerative colitis, orally administering polystyrene particles—a common plastic found in food packaging—to analyze molecular and histological interactions with the intestinal mucosa and immune system.
• Mechanism of Action: MNP exposure triggers pro-inflammatory activation of macrophages and induces gut dysbiosis, characterized by a decrease in beneficial bacterial species and an increase in potentially harmful, pro-inflammatory microbes.
• Data Point: Nanoplastic particles smaller than 0.0003 millimeters (0.3 micrometers) demonstrated the highest mobility, successfully traversing the intestinal barrier to deposit in the liver, kidneys, and bloodstream.
• Contextual Findings: The uptake of MNPs into the intestinal mucosa is significantly intensified during active inflammatory states, suggesting a feedback loop where existing inflammation facilitates further plastic accumulation.
• Primary Implication: MNPs are an underestimated environmental factor in the pathogenesis of chronic inflammatory diseases, highlighting an urgent need to evaluate the systemic health risks posed by the migration of the smallest particles into major organ systems.

New study reveals major gaps in global forest maps

A Copernicus Sentinel-2B satellite map of South Sudan shows the tropical forests, swamps and grassland that comprise the majority of the country's terrain.
Photo Credit: European Space Agency
(CC BY-SA 4.0)

Scientific Frontline: "At a Glance" Summary

• Global Dataset Discrepancy: A comparative analysis of eight major global forest datasets reveals that they concur on the identification of forest locations only 26% of the time, highlighting severe inconsistencies in digital baselines.
• Methodological Divergence: The study attributes these variations to differing technical definitions of "forest"—specifically regarding canopy cover thresholds (e.g., 10% vs. 50%)—and the specific remote sensing technologies employed to interpret land use.
• Socioeconomic Impact Data: In a specific case study of India, estimates of the population living in poverty near forests ranged dramatically from 23 million to 252 million, depending solely on the forest map utilized.
• Scale of Uncertainty: Definitional variances result in uncertainty factors of up to 10, capable of instantly reclassifying millions of hectares between "forest" and "non-forest" status in global inventories.
• Implications for Climate Policy: These discrepancies undermine the reliability of carbon storage estimates and nature-based markets, posing risks to the accurate allocation of climate finance and the validation of conservation policies.
• Proposed Resolution: The researchers introduced a decision-support flowchart to assist stakeholders in dataset selection and advocated for hybrid models that validate satellite imagery with ground-level data to improve accuracy.

How light reflects on leaves may help researchers identify dying forests

Trees at UNDERC
Photo Credit: Barbara Johnston/University of Notre Dame

Early detection of declining forest health is critical for the timely intervention and treatment of droughted and diseased flora, especially in areas prone to wildfires. Obtaining a reliable measure of whole-ecosystem health before it is too late, however, is an ongoing challenge for forest ecologists.

Traditional sampling is too labor-intensive for whole-forest surveys, while modern genomics—though capable of pinpointing active genes—is still too expensive for large-scale application. Remote sensing offers a high-resolution solution from the skies, but currently limited paradigms for data analysis mean the images obtained do not say enough, early enough.

A new study from researchers at the University of Notre Dame, published in Nature: Communications Earth & Environment, uncovers a more comprehensive picture of forest health. Funded by NASA, the research shows that spectral reflectance—a measurement obtained from satellite images—corresponds with the expression of specific genes.

Reflectance is how much light reflects off of leaf material, and at which specific wavelengths, in the visible and near-infrared range. Calculated as the ratio of reflected light to incoming light and measured using special sensors, reflectance data reveals a unique signature specific to the leaf’s composition and condition.

Arctic has entered a new era of extreme weather

Cassiope tetragona killed by a rain-on-snow event.
Photo Credit: R Treharne

Extreme weather events have become significantly more common in the Arctic over recent decades, posing a threat to vital polar ecosystems, according to new research by an international team of scientists. 

Key Takeaways:

• New research by an international team of scientists has found that Arctic regions are facing unprecedented climate conditions 

• Study has found that extreme weather events have become more common over the past 30 years, threatening plants and animals 

• Findings show hotspots for extreme weather events are Western Scandinavia, the Canadian Arctic Archipelago and Central Siberia 

• Damage from extreme weather can also affect the livelihoods of Arctic people such as reindeer herders and may also harm the ability of the Arctic to absorb carbon and slow climate change. 

Extreme weather events have become significantly more common in the Arctic over recent decades, posing a threat to vital polar ecosystems, according to new research by an international team of scientists. 

Oil residues can travel over 5,000 miles on ocean debris, study finds

Petroleum residues can survive long-distance transport by adhering to floating debris, dramatically extending how far oil pollution can travel in the marine environment.
Photo Credit: Diane Buhler, Friends of Palm Beach

When oily plastic, glass, and rubber washed ashore on Florida beaches in 2020, it appeared at first to be a local mystery. But through a collaboration that paired community observations with world-leading oceanographic and chemical expertise, scientists traced the contamination across more than 5,200 miles of ocean.

In a new study published in ACS Environmental Science & Technology, researchers from Woods Hole Oceanographic Institution (WHOI) and Northeastern University, in collaboration with community scientists from Friends of Palm Beach, show that petroleum residues can survive long-distance transport by adhering to floating debris, dramatically extending how far oil pollution can travel in the marine environment.

Using advanced ocean current modeling and chemical fingerprinting developed at WHOI, the team linked the Florida debris to a massive oil spill that occurred along Brazil’s coastline in 2019.

“This study demonstrates how plastic pollution fundamentally changes the fate of oil in the ocean,” said Chris Reddy, chemical oceanographer at WHOI and a global authority on oil spill forensics. “By hitchhiking on debris, petroleum residues can persist and move far beyond what we previously believed possible.”

Recovering reef fish populations could nourish millions of additional people each year

A new study led by King Abdullah University of Science and Technology (KAUST) Assistant Professor Jessica Zamborain-Mason shows that rebuilding depleted coral reef fish populations could significantly increase sustainable food supplies for millions of people worldwide. Published in Proceedings of the National Academy of Sciences (PNAS), the work provides the first global quantification of how much food is currently being lost due to degraded reef fish stocks and how much can be regained if reefs are restored to sustainable levels.

Drawing on one of the largest coral reef datasets assembled to date, the study analyzes more than 1,200 reef sites across 23 tropical jurisdictions. The findings come at a critical moment: reef ecosystems are experiencing widespread climate-driven impacts, and if reef fisheries are overexploited, ecosystem resilience and tropical food systems are at risk.  

“Our study provides clear, quantitative evidence of how much food tropical coastal communities are losing — and could regain — through sustainably managed reef fisheries,” said Zamborain-Mason. “These insights give governments the scientific foundation needed to strengthen food security and ecosystem resilience through effective fisheries management.” 

How a persistent chemical enters our surface waters

Image Credit: Scientific Frontline / stock image

PFAS, short for per- and polyfluoroalkyl substances, are not called “forever chemicals” for nothing. These fluorine-containing organic molecules are difficult to break down and are likely to remain in the environment for decades or even centuries, where they can accumulate in humans and animals and may have harmful effects on health. This is a compelling reason to take precautionary measures. 

The PFAS class of substances comprises thousands of chemical compounds. Not all of them have been thoroughly studied. The release, spread, accumulation, and effects of numerous PFAS are the subject of ongoing research. Among other things, researchers are focusing on TFA, short for trifluoroacetic acid. The smallest molecule in the PFAS family is formed as a degradation product of various other substances, such as many fluorinated refrigerants and propellants. Once formed, TFA is hardly degraded in the environment. “TFA formed in the atmosphere quickly enters precipitation, and from there it travels into surface waters and then into groundwater,” says Empa researcher Stefan Reimann from the Air Pollutants / Environmental Technology laboratory. 

Scientists discover what drives California's worst fire years

Two natural resource specialists walk through an area of Redwood Mountain Grove burned in the KNP Complex Fire in California’s Sierra Nevada Mountains to evaluate fire effects.
Photo Credit: National Park Service

What makes one fire season worse than another in fire-prone parts of the world like California is poorly understood, but in a new study, scientists at the University of California, Irvine reveal how clusters of lightning-ignited fires called fire complexes are the chief drivers of the most destructive fire years. It’s a finding that could help agencies better manage such fires when they occur.

“Nobody has ever looked into these kinds of fires before,” said Rebecca Scholten, a postdoctoral fellow in Earth system science and lead author of the Science Advances study. “We theorized that when two or more fires in a fire complex merge, they would just burn themselves out. But we found the opposite – the fires grow worse.”

What Is: The Anthropocene

Image Credit: Scientific Frontline / stock image

At a Glance

• The Core Concept: The Anthropocene, or "Age of Man," is a proposed geological epoch positing that human activity has superseded natural forces to become the primary driver of Earth's geological and ecological systems.
• Key Distinction/Mechanism: Unlike the Holocene—the stable epoch of the last 11,700 years that fostered human civilization—the Anthropocene represents a fundamental rupture in Earth's history where humanity operates as a geological force rather than merely a biological one. It is characterized by the human-driven alteration of the atmosphere, hydrosphere, cryosphere, and biosphere, shifting the planet into a volatile and unstable interval.
• Origin/History: The term was popularized by atmospheric chemist Paul Crutzen at the turn of the millennium (c. 2000) to describe the profound impact of humanity on the planet.

Major Frameworks/Components

• A Diachronous "Event": The scientific community increasingly views the Anthropocene not strictly as a defined epoch with a singular start date (a "golden spike"), but as an unfolding, diachronous geological event comparable to the Great Oxidation Event.
• Planetary Health Indicators: The framework highlights critical shifts such as the disruption of nitrogen and phosphorus cycles, rapid ocean acidification, and accelerating species extinction.
• Stratigraphic Alteration: The concept suggests that humanity has fundamentally altered the physical stratigraphic record of the Earth.
• Why It Matters: The Anthropocene redefines the current environmental crisis not as a series of isolated issues, but as a systemic transformation of the Earth caused by a single species. It serves as the dominant conceptual framework for understanding planetary instability and signals that the conditions necessary for known civilization are ending.

Study finds exposure to common air pollutants alters adolescent brain development

For the first time, researchers at OHSU evaluated the long-term impact of air pollution on adolescent brain health and development.
Image Credit: Scientific Frontline / AI generated

Physician-scientists at Oregon Health & Science University warn that exposure to air pollution may have serious implications for a child’s developing brain.

In a recent study published in the journal Environmental Research, researchers in OHSU’s Developmental Brain Imaging Lab found that air pollution is associated with structural changes in the adolescent brain, specifically in the frontal and temporal regions — the areas responsible for executive function, language, mood regulation and socioemotional processing.

Air pollution causes harmful contaminants, such as particulate matter, nitrogen dioxide and ozone, to circulate in the environment. It has been exacerbated over the past two centuries by industrialization, vehicle emissions, and, more recently, wildfires.

Exposure to PFAS and PCBs linked to higher odds of MS

Aina Vaivade and Kim Kultima have measured the levels of common environmental pollutants in the blood of people with MS using a mass spectrometer (pictured).
Photo Credit: Tobias Sterner/Uppsala University

People who have been exposed to both PFAS and PCBs are more likely to be diagnosed with multiple sclerosis (MS). These new research findings are based on analyses of blood samples from more than 1,800 individuals in Sweden, one of the most comprehensive studies to date on the influence of chemical environmental exposure on the development of MS. 

Multiple sclerosis (MS) is an autoimmune disease in which both genetic and environmental factors can contribute to the risk of the disease. In the current study, researchers analyzed blood from individuals who had recently been diagnosed with MS to investigate concentrations of the common environmental contaminants PFAS and PCBs. 

Storms in the Southern Ocean mitigates global warming

Visible satellite image showing storms sweeping across the Southern Ocean on 4 January 2019.
Photo Credit: NASA Worldview Snapshot

Intense storms that sweep over the Southern Ocean enable the ocean to absorb more heat from the atmosphere. New research from the University of Gothenburg shows that today’s climate models underestimate how storms mix the ocean and thereby give less reliable future projections of our climate. 

The Southern Ocean is a vast expanse of ocean encircling the Antarctic continent, regulating Earth’s climate by moving heat, carbon, and nutrients out in the world’s oceans. 

It provides a critical climate service by absorbing over 75 per cent of the excess heat generated by humans globally. The Southern Ocean’s capacity to reduce climate warming depends on how efficiently it can absorb heat from our atmosphere.  

Biodegradable wet wipes remain in rivers for more than five weeks

Photo Credit: Christine Sandu

Scientists have tested, for the first time, how biodegradable wet wipes break down when flushed rather than composted discovering that most wipes remain after five weeks – a finding the research team says challenges the marketing of these products. 

Researchers from Cardiff University’s Schools of Biosciences, Chemistry and Engineering tested two widely available brands of wipes labelled as ‘biodegradable’ in ten urban rivers and streams in Cardiff, UK 

For five weeks, the team tracked the degradation of the wet wipes in these locations by testing their tensile strength loss, and recording environmental factors such as microbial biomass, water chemistry, temperature, and river-level fluctuations. 

Fine particles in pollution are associated with early signs of autoimmune disease

Photo Credit: Chris LeBoutillier

A new study has linked air pollution exposure and immune-system changes that often precede the onset of autoimmune diseases. 

McGill University researchers analyzing Ontario data found that fine particles in air pollution are associated with higher levels of a biomarker linked with autoimmune diseases, such as systemic lupus. 

“These results point us in a new direction for understanding how air pollution might trigger immune system changes that are associated with autoimmune disease,” said Dr. Sasha Bernatsky, a James McGill Professor of Medicine and member of the McGill Centre for Climate Change and Health, the Division of Rheumatology and the Centre for Outcome Research and Evaluation. “We know some genetic factors play a role in autoimmune disease, but they don’t tell the whole story.” 

SoMAS Study: Microplastics in Oceans Distort Carbon Cycle Understanding

Plastic items, such as this part of a swimming float (blue), are often seen at ocean shorelines. These products eventually break down into microplastics, which permeate the oceans and add to the distribution of carbon along with organic matter.
Photo Credit: Luis Medina.

A study by researchers in Stony Brook University’s School of Marine and Atmospheric Sciences (SoMAS) shows that when microplastics are accidentally collected and measured with natural ocean organic particles, the carbon released by plastics during combustion appears as if it came from natural organic matter, which distorts scientists’ understanding of the ocean’s carbon cycle.

The carbon cycle in our oceans is critical to the balance of life in ocean waters and for reducing carbon in the atmosphere, a significant process to curbing climate change or global warming.

Microplastics are everywhere in the oceans. These small plastic fragments come from the breakdown of larger plastic items polluting the seas. Once they reach the sea through rivers, wastewater or runoff, they spread through coastal and open-ocean waters.

Temporary carbon removals can compensate warming from methane emissions

Photo Credit: Marita Kavelashvili

Carbon removal projects could prove vital in offsetting methane emissions – the second largest contributor to global warming. 

Nature-based schemes that aim to remove CO2 through methods such as afforestation and reforestation are criticized for being temporary – the carbon removed is often re-released once projects end – as well as fraught with risk.  

But climate change researchers have shown they can play an important role in neutralizing the environmental impact of methane. 

Methane and carbon dioxide behave differently over time: methane warms the planet much more rapidly than carbon dioxide, causing more damage in the short to medium term, but methane has little long-term impact on global temperatures as it dissipates over time.  

Heat and drought change what forests breathe out

Qingyuan County forest research site
Photo Credit: Kai Huang/UCR

Scientists have long warned that rising global temperatures would force forest soils to leak more nitrogen gas into the air, further increasing both pollution and warming while robbing trees of an essential growth factor. But a new study challenges these assumptions. 

After six years of UC Riverside-led research in a temperate Chinese forest, researchers have found that warming may be reducing nitrogen emissions, at least in places where rainfall is scarce.

The findings, published in the Proceedings of the National Academy of Sciences, are the result of UCR’s collaboration with a large team of graduate students and postdoctoral researchers stationed in China’s Shenyang City. These researchers maintained the infrastructure used to take more than 200,000 gas measurements from forest soil over six years.

The mystery of the missing deep ocean carbon fixers

Alyson Santoro Associate Professor Ecology, Evolution, and Marine Biology
Alyson Santoro's research focuses on microbes involved in nutrient cycling in the ocean, especially of the element nitrogen. This research combines laboratory experiments with field observations, and to date has used genomics, transcriptomics, proteomics and stable isotope geochemistry as tools to uncover the activity of microbes in the mesopelagic ocean.
Photo Credit: Courtesy of University of California, Santa Barbara

In a step toward better understanding how the ocean sequesters carbon, new findings from UC Santa Barbara researchers and collaborators challenge the current view of how carbon dioxide is “fixed” in the sunless ocean depths. UCSB microbial oceanographer Alyson Santoro and colleagues, publishing in the journal Nature Geoscience, present results that help to reconcile discrepancies in accounting for nitrogen supply and dissolved inorganic carbon (DIC) fixation at depth.

“Something that we’ve been trying to get a better handle on is how much of the carbon in the ocean is getting fixed,” Santoro said. “The numbers work out now, which is great.”  

Rising levels of banned toxic chemicals in otters from Wales

Photo Credit: Lilian Dibbern

New research has found that the levels of toxic industrial chemicals, which were banned over 40 years ago, are rising in otters in Wales. 

The Cardiff University Otter Project, in collaboration with Natural Resources Wales analyzed liver samples from Eurasian otters (Lutralutra) collected across Wales between 2010 and 2019. The team found Polychlorinated biphenyls (PCBs) in every otter they tested. Of the otters sampled, 16% exceeded a toxic threshold, which is known to impair reproduction. 

PCBs were once widely used in electrical equipment, paints, and plastics due to their stability and heat resistance. Although banned in the 1980s, their environmental persistence means they continue to accumulate in wildlife and can be found in high concentrations in top predators. 

Counting salmon is a breeze with airborne eDNA

A male Coho salmon, featuring the characteristic hooked nose, returns to spawn from the Oregon Coast.
Photo Credit: NOAA Fisheries

During the annual salmon run last fall, University of Washington researchers pulled salmon DNA out of thin air and used it to estimate the number of fish that passed through the adjacent river. Aden Yincheong Ip, a UW research scientist of marine and environmental affairs, began formulating the driving hypothesis for the study while hiking on the Olympic Peninsula.

“I saw the fish jumping and the water splashing and I started thinking — could we recover their genetic material from the air?,” he said.

The researchers placed air filters at several sites on Issaquah Creek, near the Issaquah Salmon Hatchery in Washington. To their amazement, the filters captured Coho salmon DNA, even 10 to 12 feet from the river. Scientists collect environmental DNA, or eDNA, to identify species living in or passing through an area, but few have attempted to track aquatic species by sampling air.