At a Glance

Two recent studies found microplastics in remote, seemingly pristine settings. Researchers were surprised to find plastics in rainwater collected from high up in the Rocky Mountains.Another team of researchers found plastics in snow collected from the Arctic and the Alps in Europe.Microplastics have been found in animals, drinking water, the deepest trenches of the oceans and the coldest reaches of the Arctic.

Teams of researchers have found microplastics in some of the most remote, pristine locations on Earth, suggesting that plastics are being swept up by the wind and carried off through the atmosphere to far-off places.

This week, a pair of studies found plastics in rainwater collected high up in the Rocky Mountains and in snow samples collected from the farthest reaches of the Arctic and in the Alps in Europe.

In the United States, researchers studying the nitrogen content of Rocky Mountain rainwater were shocked to find that collected water samples from high up on the mountains were teeming with microplastics.

"I thought maybe I should look at (the samples) under a microscope. And when I did, I was a little shocked by the amount of plastic that I saw in them … ," lead author Gregory Wetherbee, a research chemist with the U.S. Geological Survey, told CPR News.

This microscope image shows plastic materials in rainwater samples collected near 21st and Broadway in Denver. The particles, naked to the human eye, are seen here at 40X magnification.

(USGS)

Wetherbee noted that microplastics, which are less than 5 millimeters long, were the "furthest thing from my mind when we first started this project."

The team used rainwater collection sites throughout Colorado, from Arvada, a Denver suburb, to sites at altitudes of 10,000 feet in Rocky Mountain National Park.

Wetherbee said the team wasn't surprised to find plastics in the rainwater samples in the cities, but they were shocked to find them at higher altitudes in remote, pristine locations.

"That made me realize that what we had here was something that was quite significant because the question is how do those plastics get into that remote area?" Wetherbee said.

The conclusion made by the researchers, and the title of their research paper by the USGS: "It is Raining Plastics."

(MORE: Microplastics Found High in the Pristine Pyrenees Mountains in France)

Meanwhile, researchers for a separate study published this week in the journal Science Advances found a in snow samples collected in the Arctic and in the Alps. In the Arctic's Svalbard islands, the team found 10,000 plastic particles per liter.

"We expected to find some contamination but to find this many ," lead author Melanie Bergmann of Germany's Alfred Wegener Institute told the BBC. "It's readily apparent that the majority of the microplastic in the snow comes from the air."

It's not the first time microplastics have been found in remote places. The findings of both studies were similar to another study conducted recently in France, where researchers in a remote area of the Pyrenees.

Every day, an average of fall on the square meter collectors at a remote weather station in the mountains, according to the study published in Nature Geoscience.

Last year, the German team found a trapped in the Arctic's sea ice. More than 12,000 particles were found per liter in ice core samples taken from five separate Arctic locations.

(MORE: Record Amount of Microplastic Found in Arctic Sea Ice)

The latest studies, along with a growing tomb of other research, suggest that microplastics, which have been found in animals, in , in the and in the , can also be carried long distances through the air.

The German team believes the microplastics are being blown up into the air by winds and then carried long distances through the atmosphere. The mechanism behind the transport remains unclear, the scientists say.

The USGS team, on the other hand, noted that it's unclear how microplastics have accumulated and assimilated into the environment, but say the disturbing findings should serve as an important wake-up call.

"I think the most important result that we can share with the American public is that there’s ," Wetherbee told the Guardian. "It’s in the rain, it’s in the snow. It’s a part of our environment now."