The roads and vehicles that use them are responsible for 84% of the microplastics found in the atmosphere, according to the results of a new study.
Researchers at Utah State University examined various sources of microplastic air pollution discovered in the western United States over a 14-month period.
These microscopic pieces of plastic pollution are so pervasive that they affect the way plants grow, pass through the air we breathe, infiltrate the oceans, are found in the intestines of Antarctic insects and even in human bloodstream, the study authors warned. .
The US team found that 84% of the microplastics in the atmosphere come from road dust, mainly from tires, 11% from sea spray and 5% from agricultural soil.
The study’s authors found that most atmospheric microplastics come from roads, and sea spray (as bottles and packaging break down) comes second.
Researchers at Utah State University examined various sources of microplastic air pollution discovered in the western United States over a period of 14 months
Janice Brahney, Natalie Mahowald and colleagues examined major sources of atmospheric microplastics, as well as the locations in which it is concentrated.
They found microplastics on land on the surface of the ocean and plastic on the ocean on land – suggesting that it spreads through the atmosphere.
Hot spots for terrestrial microplastic sources and accumulations included Europe, East Asia, the Middle East, India and the USA, the study authors explained.
In general, the highest concentration of atmospheric microplastics was estimated to be overseas.
Depending on the size, the microplastics remained in the atmosphere from about an hour to 6.5 days, the latter long enough to take them to another continent.
Even the farthest continent on Earth, Antarctica, has received microplastic pollution from the atmosphere, despite zero microplastic emissions.
The findings suggest that even after atmospheric microplastics settle on land or in water, they can re-enter the atmosphere.
Understanding how microplastics move through global systems is essential to solving the problem, Brahney said.
“Plastics enter the atmosphere … not directly from landfills or landfills, as you might expect … but from old, broken down waste, which makes its way into large-scale atmospheric patterns,” he said. explained the team.
Roads are an important source of atmospheric plastics, in which vehicle tires rotate and launch into the sky tiny parts through strong turbulence created by vehicles.
And the ocean waves are full of insoluble plastic particles that were envelopes, soda bottles and plastic bags.
These “plastic heritage” particles move to the upper layer of water and are agitated by waves and wind and are catapulted into the air.
Sources of dust and agriculture for aerial plastics are more important in North Africa and Eurasia, while road sources have had a major impact in heavily populated regions around the world.
These microscopic pieces of plastic pollution are so pervasive that they affect the way plants grow, pass through the air we breathe, infiltrate the oceans, are found in the intestines of Antarctic insects and even in human bloodstream, the study authors warned. .
The US team found that 84% of the microplastics in the atmosphere come from road dust, mainly tires, 11% from sea spray and 5% from agricultural soil.
This study is important, Brahney said, but it is just the beginning.
“Much more work is needed on this pressing issue to understand how different environments could influence the process – humid versus dry climates, mountainous regions versus flat areas,” she said.
“People have not slowed down their production or use of plastic, so these questions become more pressing with each passing year.”
The findings were published in the journal Proceedings of the National Academy of Sciences.