Microplastics Have Been Found in the Arctic Snow at 'Unexpectedly High' Quantities

Scientists have found microplastics at "unexpectedly high" quantities in the Arctic snow. The discovery, scientists say, shows these tiny particles of plastic are being transported to one of the most remote regions of the planet through the atmosphere, with the wind carrying it north then dumping it to the ground via precipitation.

Microplastics have been found at some of the highest and lowest points of Earth. They have been detected in France's Pyrenees mountains all the way down to the Mariana Trench—the deepest known part of the sea. They have even entered global food chains, with one study showing microplastics can be found in human feces around the world.

These fragments, which measure less than 0.2 inches, are created from the breakdown of larger pieces of plastic waste, as well as from industrial sources—including cosmetics and synthetic clothing.

Increasingly, research has shown the potential health impacts of microplastics, with lung cancer risk linked to inhaling the particles. However, how these miniscule bits of plastic are transported around the globe is unclear—and understanding this is paramount to understanding the risks posed.

In a study published in Science Advances, researchers led by Melanie Bergmann, from the Alfred Wegener Institute in Germany, analyzed concentrations of microplastics in European cities and regions of the Arctic Ocean to find out how the particles were traveling so far.

"We had found high levels of microplastics in Arctic sea ice and deep-sea sediments in earlier studies, so we knew that it had to come from somewhere," Bergmann told Newsweek.

The team studied snow samples taken from regions in the Arctic Ocean between 2015 and 2017. They also looked at samples from Bremen, a city in Germany, and a remote part of the Swiss Alps. Their findings showed that while the Arctic snow samples were lower than the other two sites, the quantities of microplastics were "unexpectedly high."

"While snow from Europe was more polluted, the third most contaminated sample came from an Arctic ice floe—14,000 microplastic particles per liter of melted snow in Arctic snow," she said.

Bergmann said that while microplastics are believed to be transported by the Gulf Stream, their findings also point to atmospheric transportation. Most of the particles were found to be the smallest measurable size range—less than 11 micrometers (0.0004 inches). The team says particles were likely transported to the Arctic in the atmosphere, being deposited in the snow during precipitation.

"The study shows that atmospheric transport and fallout is an important pathway and mode of spread for microplastics enabling them to reach the remotest parts of our planet. As such, these should also be monitored in air pollution monitoring schemes," Bergmann said.

The small size of the microplastics is important, she said, as it is more likely it will be ingested by a wider range of organisms. "The smaller the particle the higher the likelihood of passing cell membranes or into organs."

In a statement, she added: "Once we've determined that large quantities of microplastic can also be transported by the air, it naturally raises the question as to whether and how much plastic we're inhaling."

Next, the team hopes to study how much microplastic is present in deeper water layers of the Arctic Ocean, and to find out if rivers play a role in the pathway of plastic into the sea.