According to the results of a new study, roads and vehicles are responsible for 84 percent of the microplastics found in the atmosphere.
Researchers at Utah State University have been investigating various sources of atmospheric microplastic pollution over a 14-month period in the western United States.
These microscopic pieces of plastic pollution are so pervasive that they affect how plants grow, blow through the air we breathe, penetrate the oceans, occur in the intestines of insects in Antarctica and even in the human bloodstream, the study’s authors warned.
The U.S. team found that 84 percent of the microplastics in the atmosphere come from road dust, mainly tires, 11 percent from the ocean and five percent from agricultural land.
Study authors found that most atmospheric microplastics came from roads, with sea spray (if bottles and packaging failed) coming in second place
Researchers at Utah State University have been investigating various sources of microplastic pollution in the atmosphere in the western US over a 14-month period.
Janice Brahney, Natalie Mahowald and colleagues investigated the main sources of atmospheric microplastics, as well as the places where they were concentrated.
They found microplastics of the land on the surface of the ocean and plastic of the ocean on land – suggesting that it was spreading through the atmosphere.
Study authors included the hotspots for terrestrial microplastic sources and accumulation: Europe, East Asia, the Middle East, India, and the United States.
In general, the greatest concentration of atmospheric microplastics is estimated across the ocean.
Depending on the size, microplastics remained in the atmosphere for about one hour to 6.5 days, the latter long enough to take it to another continent.
Even the most remote continent on earth, Antarctica, received microplastic pollution from the atmosphere, despite the fact that it had no microplastic emissions.
The findings suggest that even after atmospheric microplastics sink to land or water, they can re-enter the atmosphere.
Understanding how microplastics move through global systems is essential to solving the problem, Brahney said.
“Plastic enters the atmosphere … not directly from garbage cans or landfills as you would expect … but from old, decomposed waste moving in large-scale atmospheric patterns,” the team explained.
Roads are a large source of atmospheric plastic, where the tires of the vehicle twist and the small stretches start skyward through turbulent vehicles.
Ocean waves are also full of insoluble plastic particles that used to be food packaging, soft drink bottles and plastic bags.
These ‘legacy plastic’ particles bounce to the top layer of water and are chopped by waves and wind and catapulted into the air.
Dust and agricultural resources for plastics in the air are more prominent in North Africa and Eurasia, while resources produced by road have had a major impact in heavily populated regions around the world.
These microscopic pieces of plastic pollution are so pervasive that they affect how plants grow, blow through the air we breathe, penetrate the oceans, occur in the intestines of insects in Antarctica and even in the human bloodstream, the study’s authors warned.
The U.S. team found that 84 percent of the microplastics in the atmosphere came from road dust, mainly tires, 11 percent from sea spray and five percent from agricultural land.
This study is important, Brahney said, but it’s just the beginning.
“Much more work is needed on this urgent problem to understand how different environments can affect the process – wet climates versus dry, mountainous areas versus rural areas,” she said.
“The world has not slowed down the production or use of plastics, so these questions are becoming more urgent every year.”
The findings were published in the journal Proceedings of the National Academy of Sciences.