Microplastics are ending up in the Arctic after being carried thousands of miles by wind currents, according to a new study in the journal Science Advances.

The tiny particles get swept up by blasts of air and scattered across the world, eventually making it to the most remote regions of the planet. Although direct plastic pollution is almost nonexistent in the Arctic, indirect pollution is piling up in ways that have largely unknown consequences, according to the report.  

“There’s a lot [of microplastic] out there, and this is one additional pathway that we haven’t given the attention required so far,” Melanie Bergmann, the lead author of the report, told the Scientific American. 

The authors note that the Arctic is still relatively uncontaminated by global standards but the mere presence of microplastics in the area shows how the problem of plastic pollution is getting out of control. 

Microplastics form as larger pieces of plastic break down into tiny particles through regular wear and tear, exposure to harsh environmental conditions, and industrial processes. For example, a typical load of laundry releases around 700,000 microplastics into the atmosphere.  

Bergman’s team collected samples of snow on the Norwegian archipelago of Svalbard to study the extent of microplastic pollution. The researchers chose snow, as opposed to water samples, to study because it collects and holds onto all sorts of particles from the atmosphere. It also allowed them to isolate plastic carried by the wind as opposed to ocean currents. 

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The microplastics likely wound up in the snow during a precipitation event after being carried by the wind, the researchers note. 

The team compared the samples to snow collected in the Swiss Alps and the German city of Bremen. 

The amount of plastic found in Svalbard was less than the plastic found elsewhere. The types of plastic differed as well, suggesting that different plastics are more likely to travel through the wind than others. 

Bergmann’s study didn’t explore the consequences of microplastic pollution. But her research adds to a growing body of work that shows a world awash in invisible bits of plastic. 

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Taken together, the studies will likely spur further research into the health effects of microplastic consumption, according to Scientific American. 

Already, it’s been shown that humans ingest an estimated 70,000 microplastics annually by eating food, drinking water, and breathing air. It’s conceivable that the average person is taking in far more microplastics, especially because some are microscopic in size. 

Microplastics can be inherently harmful to humans, and can also pick up harmful toxins while circulating through the global environment. 

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The authors of the report speculate that breathing in microplastics could penetrate deep into the lungs, causing extensive and long-term health problems. 

Although countries are beginning to take action to curb plastic production and improve waste management facilities, plastic pollution is expected to rise in the years ahead.