Some peaks throughout the Pyrénées Mountains of France stand more than 10,000 feet tall. Across the mountains’ ridges and valleys, adventurous visitors may spot a brown bear or a yellow lily, one of the wildflowers of the Pyrénées. But this mountain range is home to something else too, something not always visible to the human eye. And that’s plastic.
A study out Monday in Nature Geoscience found that wind can take tiny plastic particles known as microplastics for a ride, dumping them on unsuspecting mountaintops far from human settlements—like the Pyrénées. It’s one of the first studies to show how these particles move long distances through the air in what is likely to be a growing area of research.
The team of researchers from France and the United Kingdom spent five months, from November 2017 to March 2018, sampling the air for any plastic particles that made their way to this so-called pristine landscape. The researchers accomplished this by collecting rain, snow, and dry particulates that travel via wind. They found nearly 4,000 plastic particles per square feet land on this part of the mountains a day.
The scientists can’t be sure, but they imagine that the plastic is coming from some smaller towns no farther than 60 miles from their sampling site. Their data can’t yet prove that the plastics travel distances farther than this. However, if atmospheric winds are capable of moving around Sahara dust thousands of miles away, they might just do the same for flecks of plastic.
Most of the particles atop Pyrénées were tiny microplastics no larger than the largest pollen or plant spore. The team could count them using only microscopes. In order to avoid contaminating samples with plastic from synthetic clothes, collectors were expected to wear cotton.
The study is yet another reminder of how invasive plastic is. It’s in our beer, table salt, in poor sea turtles, and even the Arctic. That’s why Susanne Brander, an assistant professor at Oregon State University who studies this junk and wasn’t involved with the study, was not at all surprised by its findings.
“It seems scientists are finding plastic just about everywhere they look for it,” Brander told Earther in an email. “Small plastic debris and fibers are definitely lightweight enough to be transported in the air.”
Plastic’s planetary takeover is why states like New York and California are pushing for bans on plastic bags and straws. The only way to avoid this stuff winding up in our environment is by reducing it at the source—us. In 2015, the U.S. generated 34.5 million tons of plastic. Most of it went to the trash, not recycled or reused. Wherever plastics wind up, they’re liable to harm local wildlife, in addition to emitting greenhouse gases like methane when they’re exposed to the sun, as a study last year found.
There’s still a lot we don’t know—and are learning—about our waste, but next time you go on a hike, take a deep breath and try not to smell the plastics.