New Research Reveals Land Releases Over 20 Times More Microplastics Than Oceans

A new study finds land releases 20 times more airborne microplastics than oceans. These particles spread globally, enter the air we breathe, and may pose serious health risks.

Microplastics

We're all breathing in tiny, invisible plastic bits called microplastics that are floating in the air and travelling across the globe. But where do they really come from? For a long time, we've had it all wrong. A new study shows that land, and not the sea, is the main culprit, releasing over 20 times more microplastic particles into the air. This finding challenges everything we previously believed. Scientists also discovered that earlier models were actually overestimating the total amount of plastic in the air.

The problem with microplastics

The air acts like a superhighway for these microplastics, carrying them to the most remote parts of our planet. This is a huge worry because humans and animals end up inhaling these particles, raising concerns about potential health problems. After travelling through the air, these microplastics eventually fall back to Earth, adding to the pollution in our oceans and on our land.

Land is the bigger problem, by 20 times

A new study from the Department of Meteorology and Geophysics at the University of Vienna has given us a much clearer picture of where these airborne microplastics originate. Using global measurements and computer models, researchers have estimated the number of particles coming from both land and sea sources.

Their main finding is a real shocker: land releases 20 times more microplastic particles into the air than the oceans do. This groundbreaking research was recently published in the journal Nature.

Challenging old beliefs

Scientists have known for a long time that microplastics are present in the air all over the world, eventually settling in faraway and isolated locations. These particles come from direct sources like tyre wear and fibres from clothes, and also from already polluted land and sea surfaces when particles get kicked back up into the air.

Until now, the exact amount of these emissions and the contribution of each source wasn't properly understood. Previous studies mostly pointed to the ocean as the main source, but these new findings have turned that assumption on its head.

How they figured it out

To understand the problem better, researchers Ioanna Evangelou, Silvia Bucci, and Andreas Stohl gathered 2,782 individual microplastic measurements from studies conducted across the globe. They then compared these real-world observations with the results of a transport model that used three different emission estimates.

This comparison revealed a major problem. The model consistently predicted that there were many more microplastics in the air and settling on the Earth's surface than were actually found. This discrepancy helped the researchers adjust the model and separately refine the emission estimates from land and ocean sources.

How do microplastics move in the atmosphere?

This study is a crucial step in understanding how microplastics move and spread globally through the atmosphere. However, there are still significant uncertainties. "The state of the data is still not satisfactory, and major uncertainties remain. More measurements are needed to find out how much microplastic comes from traffic and how much from other sources. The size distribution of the particles is also very uncertain, which means the total amount of plastic transported in the atmosphere is not clear," the research team reported.