What Is: Microplastics

Microplastic
Credit: Scientific Frontline

The Invisible Tide of Plastic

The modern era has been defined, in part, by the versatility and ubiquity of plastic. Yet, this celebrated 20th-century material has given rise to a paradoxical form of pollution—one so pervasive and minute that its scale was largely unrecognized until recently. Microplastics, the synthetic dust of our industrial age, represent a global environmental challenge of unprecedented complexity. These tiny particles, born from the fragmentation of larger debris and the intentional design of microscopic products, have infiltrated every corner of the planet. Scientific expeditions have confirmed their presence from the summit of Mount Everest to the abyssal depths of the Mariana Trench. More alarmingly, this invisible tide has crossed the final frontier, entering the human body itself, with researchers detecting microplastic particles in human blood, lung tissue, and even the placenta.

The ubiquity of microplastics signals a fundamental disruption of planetary systems. They are not merely inert debris but active agents in the environment, interacting with ecosystems and organisms in complex and often detrimental ways. Their journey spans the globe, carried by ocean currents, river systems, and atmospheric winds, connecting the most remote wilderness to the most densely populated urban centers in a shared system of contamination. This report provides a definitive, evidence-based synthesis of the current scientific understanding of microplastics. It aims to dissect the full scope of this issue, beginning with a fundamental definition of the pollutant and a detailed accounting of its myriad sources. It will then trace the environmental fate and transport of these particles through aquatic, terrestrial, and atmospheric systems. Finally, the report will conduct an exhaustive analysis of their multifaceted impacts on ecological integrity and human health, concluding with a critical evaluation of the policies, technologies, and strategies required to mitigate this pervasive threat.

Study first to show if nesting heat affects sea turtle hatchling ‘IQ’

A loggerhead hatchling goes through the Y-maze to test its learning abilities.
Photo Credit: Sarah Milton, Florida Atlantic University

As sand temperatures continue to rise, concerns about the future of sea turtles are growing. Hotter nests not only skew sex ratios – producing more females – but also reduce hatchling survival, slow growth, and increase the likelihood of physical deformities. Yet one important and often overlooked question remains: does this heat also affect cognitive ability – how well hatchlings can learn, adapt and respond to the rapidly changing world they face from the moment they emerge?

A new study by researchers at Florida Atlantic University’s Charles E. Schmidt College of Science offers a surprising glimmer of hope. They are the first to test whether incubation temperature affects cognitive ability in loggerhead (Caretta caretta) hatchlings – how well they can learn, adapt and problem-solve. While animal cognition has been widely studied in birds and mammals, much is yet to be discovered in reptiles.

Using a Y-maze and a visual discrimination task, the researchers trained hatchlings incubated at two female-producing temperatures (88 F and a hotter 91 F) and then tested their ability to “reverse train” when the task rules changed. Eggs were collected during the summers of 2019 and 2020 from nesting beaches in Palm Beach County.

Microbial DNA sequencing reveals nutrient pollution and climate change reinforce lake eutrophication

Lake 227 of the Experimental Lakes Area.
Photo Credit: Rebecca Garner

The algal blooms increasingly seen in Canadian lakes have been linked to both nutrient pollution from agricultural runoff and climate change. However, a new Concordia-led study using DNA sequencing of lakebed microbes reveals that these two drivers amplify each other in ways that profoundly affect the health of lake ecosystems.

Using records and samples from the International Institute for Sustainable Development Experimental Lakes Area (ELA), a group of 58 lakes in northwestern Ontario designated freshwater research facilities, the researchers paired environmental monitoring data dating back more than five decades with paleogenetic reconstructions from lakebed microbes dating back more than a century.

By sequencing DNA found in lake sediments, the researchers got insight into past algal communities’ composition and compare them to communities today. This provided critical insight into how those communities changed over decades.

“The sediment DNA archives gave us a chronology of these lakes’ history,” says lead author Rebecca Garner, PhD 2023, and currently a postdoctoral fellow at the University of California, Berkeley. “This is the first study to show that we can reconstruct the community dynamics of that ecosystem and dramatically expands the diversity of microorganisms that we were able to study.”

The study was published in the journal Environmental Microbiology.

Climate change is supercharging Europe’s biggest hail

Climate experts from Newcastle University, the Met Office and the University of Bristol used European-wide km-scale simulations to model future changes to hail with global warming. Published in the journal Nature Communications, the findings show that, under a high-emissions scenario (RCP8.5), severe hail is likely to become less common, except potentially for very large hail.

Severe hail has a diameter of 2 cm, while a diameter of 5 cm or more is considered very large. Bigger hailstones cause more damage than smaller ones, and even a small increase in their size could outweigh any benefits from having fewer hailstorms overall.  

The researchers attribute this decrease to more than one factor. Hail forms higher in the atmosphere as it warms, where storm updrafts could be weaker, and this gives hail more time to melt before reaching the ground. Another factor is the weakening large scale circulation, affecting the vertical profile of winds and leading to environments not beneficial for thunderstorm organization.

Importantly, the authors found that future warm seasons feature a warmer thunderstorm type similar to hail-producing storms found in the tropics, where the largest hailstones can still reach the surface. The findings suggest that, in the future, these storms will become most frequent over southern Europe, leading to regional increases in severe hail frequency.

Grassland Butterflies – Important Indicators of the State of Nature

Small Copper (Lycaena phlaeas), a species for which the index shows a positive trend.
Photo Credit: Werner Messerschmid

With the Grassland Butterfly Index for Germany, UFZ scientists are providing important input for the implementation of the EU Nature Restoration Regulation.

One of the goals of the EU Nature Restoration Regulation, which came into force in 2024, is to halt species loss and preserve important ecosystem services provided by agricultural landscapes. Scientists at the Helmholtz Centre for Environmental Research (UFZ), in collaboration with the Senckenberg German Entomological Institute (SDEI), have now calculated the Grassland Butterfly Index for Germany – an indicator of the state of biodiversity proposed in the EU regulation. The results, published in the journal Nature Conservation, show a negative trend, especially in recent years. For their calculations, the researchers were able to draw on 4 million observation data collected at the UFZ over the last 20 years as part of the ‘Butterfly Monitoring Germany’ program.

Wildfire Smoke May Lead to Thousands More U.S Deaths

Mammoth Mountain in California’s Sierra Nevada Range on September 8, 2025. The photo reveals significant haze and smog, much of that the result of continual wildfires in the state.
Photo Credit: Marshall Burke.

A study led by Stony Brook University faculty and published in Nature projects that smoke exposure from wildfires in the coming decades toward 2050 could result in tens of thousands of excess deaths in the United States.

This projection, by a national team of investigators led by Stony Brook’s Minghao Qiu, is based on research that assesses wildfire activity in an increasingly dry and warming climate.

Wildfires have significantly increased in recent years, often in the western U.S. but also in other regions. Warmer, drier conditions are increasing the scope, damage, and exposures to people from wildfires. The study details the use of historical data from wildfires and smoke pollution, along with statistical models and machine learning tools to estimate deaths caused by exposure to smoke particulates in climate change scenarios.

Deaths from wildfire smoke result from inhaling a complex mix of chemicals. Wildfires can expose large numbers of people to these toxic pollutants for days or weeks at a time, contributing to deaths up to three years after the initial exposure, according to the study.

Rivers in the Sky, Arctic Warming, and What this Means for the Greenland Ice Sheet

Photo Credit: Beau Mori

 “Atmospheric rivers” are large-scale extreme weather systems that are making headlines more frequently. When viewed in satellite images, they appear just as described – like rivers in the sky. Though they are often reported in places like California, these weather systems have the potential to bring high heat and dump disastrous amounts of precipitation on areas throughout the mid and high latitudes.

A team of researchers, including UConn Department of Earth Sciences associate professor Clay Tabor and Ph.D. student Joseph Schnaubelt, looked at how atmospheric rivers impacted the Greenland Ice Sheet in the past to get a better understanding of how these weather systems may enhance melting in the Arctic as the climate continues to warm. Their results are published in AGU Advances.

An important question that paleoclimate scientists like Schnaubelt and Tabor are trying to answer is how the Arctic will respond to climate change, and for this they focused deep into the past on a time called the Last Interglacial, between 130,000 and 115,000 years ago.

“Earth goes through glacial cycles, and the Last Interglacial was the last time the Arctic was warmer than present day,” says Schnaubelt. “We know that that’s the direction we’re headed toward, and we wanted to see how atmospheric rivers impacted the Greenland Ice Sheet.”

Greener rocket fuels on the horizon

SpaceX Falcon Heavy Launch
Photo Credit: SpaceX

Studying safer, cheaper rocket and missile fuels that could reduce health and environmental risks is the focus of a new $800,000 grant awarded to the University of Hawaiʻi at Mānoa Department of Chemistry by the U.S. Air Force Office of Scientific Research. The project will be led by principal investigator Professor Rui Sun with co-principal investigator Professor Ralf I. Kaiser.

The grant falls under a broader push toward green chemistry—designing chemical products and processes that reduce or eliminate hazardous substances. Current propellants can be expensive and toxic, creating risks during manufacture, storage and transport. The research seeks to help lower costs for space exploration while reducing risks to workers and communities.

Wolf protection downgrade highlights need for adaptive conservation frameworks

The protected category means greater flexibility in managing wolf populations
Photo Credit: Marcel Langthim

Scientific Frontline: "At a Glance" Summary

• Main Discovery: The European Parliament's decision to downgrade wolf status from "strictly protected" to "protected" exposes the rigidity of current conservation frameworks and demands a transition to adaptive management systems suited for recovered species.
• Methodology: A collaborative study by the University of York and Stockholm Resilience Centre analyzed the policy shift and recommended a four-pillar approach—clear targets, adaptive tools, fair cost redistribution, and enhanced dialogue—published in Conservation Letters.
• Key Data: Wolf populations in Europe surged by 58% over a single decade, marking a significant recovery alongside increases in brown bear, lynx, and wolverine numbers.
• Significance: This legislative change sets a historic precedent for downlisting species in the EU, shifting focus from extinction prevention to managing coexistence and potential conflicts in human-dominated landscapes.
• Future Application: The proposed framework calls for standardized "favorable conservation status" metrics, zoning strategies to manage conflict areas, and improved cross-border monitoring systems involving local stakeholders.
• Branch of Science: Conservation Science and Environmental Policy
• Additional Detail: Experts warn that successful coexistence depends on "social legitimacy," requiring that conservation burdens are not disproportionately placed on rural communities and that management is coordinated across national borders.

Researchers Uncover a Major Shift in U.S. Landscape: ‘Wild’ Disturbances Are Overtaking Human-directed Changes

Disturbances like hurricanes and fires reshape the landscape and play vital roles in Earth’s systems, therefore, understanding what drives these kinds of disturbances is important for projecting what changes may be ahead.
Photo Credit: Malachi Brooks

If it feels like headlines reporting 100 or 1,000-year floods and mega fires seem more frequent these days, it’s not your imagination.

A project led by researchers from UConn’s Global Environmental Remote Sensing (GERS) Lab has yielded surprising insights into land disturbances and disasters in the United States since the late 1980s, including a shift in what drives those disturbances, and how they are increasing with frightening intensity and frequency. Their findings are published in Nature Geoscience.

The research is the result of a decade-long project to perform a CONterminous United States (CONUS)-wide disturbance agent classification and mapping project, explains GERS Director and Associate Professor in the Department of Natural Resources and the Environment in the College of Agriculture, Health and Natural Resources (CAHNR) Zhe Zhu. The ambitious project involved the careful analysis of Landsat satellite data spanning more than 40 years.

Disturbances like hurricanes and fires reshape the landscape and play vital roles in Earth’s systems; therefore, understanding what drives these kinds of disturbances is important for projecting what changes may be ahead.

Methane production may increase as Arctic lakes warm

 

Fältarbete vid sjöar nära Abisko naturvetenskapliga station.
Photo Credit: Sofia Kjellman

A warmer and wetter climate makes lakes more productive – which in turn leads to more methane being released from sediments. A new study involving Umeå University shows that Arctic lakes may contribute even more to the greenhouse effect in the future.

Methane is more than 25 times stronger as a greenhouse gas than carbon dioxide. Arctic lakes account for a significant share of global methane emissions, but until now, knowledge about the processes in northern lakes has been limited. An international team of researchers from Norway, Sweden and Spain has now shown that methane production varies greatly between lakes and is closely linked to their characteristics.

The researchers investigated ten lakes on Svalbard and in the subarctic region of Scandinavia, three of them via the Abisko Scientific Research Station. They found that most methane production occurs in the top ten centimeters of lake sediments, where there is abundant organic matter and favorable conditions for microbes.

Coral reefs set to stop growing as climate warms

Dead reef crest on Mexico's Caribbean coast.
Photo Credit Chris Perry

Most coral reefs will soon stop growing and may begin to erode – and almost all will do so if global warming hits 2°C, according to a new study in the western Atlantic.

An international team, led by scientists from the University of Exeter, assessed 400 reef sites around Florida, Mexico and Bonaire.

The study, published in the journal Nature, projects that more than 70% of the region’s reefs will stop growing by 2040 – and over 99% will do so by 2100 if warming reaches 2°C or more above pre-industrial levels.

Climate change – along with other issues such as coral disease and deteriorating water quality – reduces overall reef growth by killing corals and impacting colony growth rates.

To understand how changing reef ecology is impacting reef growth potential – in other words, how the balance of living organisms translates into vertical “accretion” (reef-building) – the team analysed fossil reefs from across the tropical western Atlantic region to improve understanding of how reef growth rates vary depending on the types of coral present.

Sandy Seafloors: An Overlooked Source of Greenhouse Gas

Photo Credit: Walter Frehner

A new study reveals that methane can form in the upper layers of sandy seabeds — something that has taken scientists by surprise. Special microorganisms are at work, and the phenomenon may be happening along coastlines all over the world.  

Methane is a powerful greenhouse gas, produced in many natural environments by microorganisms.  

Until recently, scientists believed these microbes were intolerant of oxygen and could only survive in oxygen-free zones. But new research shows they can, in fact, persist in oxygenated environments — lying dormant until the oxygen disappears. That means an entirely new source of methane emissions has just been discovered.  

“We do not yet know how much methane these microbes are producing. That is the next big question. But we suspect the contribution is significant and widespread in sandy coastal zones. This is not something confined to a few isolated spots on the globe,” says Ronnie N. Glud, professor at the Department of Biology and an expert in biogeochemistry.  

Research yields eco-friendly way to separate, recycle refrigerants tied to climate crisis

Lead author Abby Harders, who earned her doctorate in chemical and petroleum engineering at the University of Kansas, now serves as head of research and development at Icorium Engineering, situated in KU’s Innovation Park.
Photo Credit: Max Jiang

A scholarly report in the journal Science Advances from researchers at the University of Kansas shows a new eco-friendly method for separating the chemicals found in common refrigerants for easier recycling at industrial scale.

“The motivation of this work is to enable separation of highly complex gaseous refrigerant mixtures,” said lead author Abby Harders, who performed the research as a KU doctoral student in the research group of co-author Mark Shiflett, Foundation Distinguished Professor of Chemical and Petroleum Engineering. “This effort has been driven by climate legislation phasing out certain hydrofluorocarbon (HFC) refrigerants.”

The paper's key innovation uses membranes — amorphous fluorinated polymers, to be specific — that efficiently isolate complex refrigerant mixtures. Other separation methods, like distillation, are less effective because of the complex composition of the mixtures. Harders said the membranes are fabricated to allow some gases to pass through while restricting others — resulting in effective purification.

To demonstrate the technology could scale to industrial viability, the team — including many associated with KU’s Wonderful Institute for Sustainable Engineering — developed a custom-coating process to create submicron coatings on the membrane’s porous supports, creating composite hollow fibers. The results show a functional prototype, proving the technology’s usefulness to firms engaged in refrigerant recovery and reuse. 

Engineers Design New Autonomous System to Monitor Arctic Ice Melt

Photo Credit: Bernd Hildebrandt

The rapid melting and thinning of the Arctic ice have sparked serious concerns in the scientific community. In addition, sea ice thickness also has decreased, which makes ice cover more vulnerable to warming air and ocean temperature.

Understanding the ecological role of sea ice in the Arctic is crucial, particularly because the extent of sea ice in the region has been decreasing at an unprecedented rate. What would happen to the Arctic marine ecosystem if the sea ice melted even faster? To answer these questions, a long-term monitoring and data collection system is necessary in the harsh Arctic environment.

However, direct observation is challenging as satellite sensors have a coarse spatial resolution and cannot detect the fine fractal structure of the ice. Deploying human-crewed ships to the area is also difficult due to extreme weather conditions and obstacles posed by floating broken ice. Moreover, traditional ocean observation methods offer limited temporal and spatial coverage, while drones and autonomous underwater vehicles (AUVs) are hindered by energy constraints that restrict their research potential.

To overcome these challenges, researchers from the College of Engineering and Computer Science at Florida Atlantic University have proposed a design of an alternative, autonomous observational method, which holds promise for improving the autonomy of marine vehicles, aiding in maritime missions, and gaining a deeper understanding of how melting Arctic sea ice affects marine ecosystems.

Women of Science: A Legacy of Achievement

Future generations to pursue their passions and break down barriers in the pursuit of knowledge.
Image Credit: Scientific Frontline stock image

Throughout history, women have made groundbreaking contributions to science, despite facing significant societal barriers and a lack of recognition. Their relentless pursuit of knowledge and innovation has shaped our understanding of the world and paved the way for future generations of scientists. This article celebrates the achievements of some of these remarkable women, highlighting their struggles and the impact of their work.

The women featured in this article, along with countless others throughout history, have made invaluable contributions to the advancement of science. Their achievements, often accomplished in the face of adversity and societal barriers, have shaped our understanding of the world and paved the way for future generations of scientists. These women demonstrate the power of perseverance, the importance of challenging established norms, and the profound impact that individual dedication can have on scientific progress. By recognizing and celebrating their legacies, we not only honor their contributions but also inspire future generations to pursue their passions and break down barriers in the pursuit of knowledge.

Air pollution clouds the mind and makes everyday tasks challenging

Photo Credit: Chris LeBoutillier

People’s ability to interpret emotions or focus on performing a task is reduced by short-term exposure to particulate matter (PM) air pollution, potentially making everyday activities, such as the weekly supermarket shop, more challenging, a new study reveals.

Scientists discovered that even brief exposure to high concentrations of PM may impair a person’s ability to focus on tasks, avoid distractions, and behave in a socially acceptable manner.

Researchers exposed study participants to either high levels of air pollution - using candle smoke - or clean air, testing cognitive abilities before and four hours after exposure. The tests measured working memory, selective attention, emotion recognition, psychomotor speed, and sustained attention.

Publishing their findings in Nature Communications, researchers from the Universities of Birmingham and Manchester reveal that selective attention and emotion recognition were negatively affected by air pollution – regardless of whether subjects breathed normally or only through their mouths.

Air pollution impacts an aging society

Age-related health impacts of PM2.5.
Annual average AVSL (age-adjusted value of statistical life) and variation of premature deaths attributable to PM2.5 among individuals in different age groups from 2001 to 2019 across Japan’s 47 prefectures.
Image Credit: ©2025 Long et al.
(CC-BY-ND)

Air pollution is a growing health issue worldwide, and its impacts are often underestimated in aging societies like Japan. A new study led by researchers from the University of Tokyo highlights how fine particulate pollution, or PM2.5, not only worsens health outcomes, but also creates significant socioeconomic challenges in regions with aging populations and limited medical resources. The researchers hope these findings motivate policymakers to tackle the interrelated issues behind this problem.

PM2.5 refers to microscopic particles of pollution small enough to penetrate deep into the lungs and bloodstream, leading to severe respiratory and cardiovascular diseases. PM2.5 are small enough to evade the body’s natural defenses in the nose and throat, making direct prevention difficult. This becomes especially problematic in elderly populations.

“As we age, our immune systems weaken and our bodies are less able to defend against pollutants. Even moderate exposure can exacerbate pre-existing conditions, leading to higher hospitalization rates and premature mortality,” said lead author Associate Professor Yin Long. “Our study provides new insights into impacts of PM2.5 in aging regions, with a particular focus on the mismatch between those impacts and regional medical resource distribution.”

Microplastics discovered in Antarctica

A view over the Ellsworth Mountains, West Antarctica.
Photo Credit: Steve Gibbs, BAS

Scientists have discovered microplastics in the snow near some of Antarctica’s deep field camps, revealing how far-reaching plastic pollution has become. While not new, it’s the first time these tiny pieces of plastic have been found in remote locations.

The study was conducted at field camps, at Union Glacier and Schanz Glacier (near the Ellsworth Mountains), where researchers were carrying out field work, and the South Pole where the US Antarctic Program has a research station. It is the first time a new and advanced technique has been used to detect microplastics as small as 11 micrometers (about the size of a red blood cell) in the snow in Antarctica. The study is published this week (6 February 2025) in the journal Science of the Total Environment.

The findings surprised the team as microplastics were found at concentrations ranging from 73 to 3,099 particles per liter of snow. Most of these particles (95%) were smaller than 50 micrometers (0.005 cm, the size of most human cells), suggesting previous studies may have underestimated the extent of microplastic pollution in the region due to less sensitive detection methods.

Previous methods involved hand-picking particles and fibers out of samples for laboratory analyses. However, the newer technique involves melting snow through filter paper and scanning this at a high resolution, using infrared spectroscopy, so any plastics above 11 micrometers can be identified.

Recycling the unrecyclable

Recovered carbon fibers.
This might look like something you’d see on the floor of a barber’s shop, but it’s actually a clump of reclaimed carbon fibers. Photo Credit: ©2025 Jin et al.
(CC-BY-ND)

Epoxy resins are coatings and adhesives used in a broad range of familiar applications, such as construction, engineering and manufacturing. However, they often present a challenge to recycle or dispose of responsibly. For the first time, a team of researchers, including those from the University of Tokyo, developed a method to efficiently reclaim materials from a range of epoxy products for reuse by using a novel solid catalyst.

There’s a high chance you are surrounded by epoxy compounds as you read this. They are used in electronic devices due to their insulating properties; clothing such as shoes due to their binding properties and physical robustness; building construction for the same reason; and even in aircraft bodies and wind turbine blades for their ability to contain strong materials such as carbon fibers or glass fibers. It’s hard to overstate the importance of epoxy products in the modern world. But for all their uses, they inevitably have a downside: Epoxy compounds are essentially plastics and prove difficult to deal with after their use or at the end of the life of an epoxy-containing product.