Bremerhaven (dpa) - With snow trickle microplastic particles from the air to the earth's surface - even in the remote Arctic.

The tiny particles of less than five millimeters in size are transported in the atmosphere and can be distributed over long distances, reports a research team led by the Alfred Wegener Institute for Polar and Marine Research (AWI) in Bremerhaven. Therefore, it is obvious that the air is heavily contaminated with microplastic. Potential health effects should be investigated in the future, the researchers write in the journal Science Advances.

Melanie Bergmann and her colleagues analyzed snow samples from Heligoland, Bavaria, Bremen, the Swiss Alps and the Arctic, from both the Svalbard archipelago and several ice floes. They melted the snow, filtered the water and examined the residues by infrared spectroscopy. This allowed the plastic residues to be detected and analyzed.

The scientists found microplastic in almost all samples examined. The snippet content was lower in the Arctic snow samples than in the European samples, but it was still "substantial". On average, 1760 particles per liter of meltwater were found in the Arctic samples. On an ice floe, 14,400 particles had been collected per liter. For comparison: The most heavily loaded sample - taken next to a highway in Bavaria - contained 154,000 particles per liter. The size of the particles ranged from 11 to 474 microns (millionths of a meter), with the very small ones predominating: 80 percent of all particles were smaller than 25 microns.

The particles are, inter alia, paint particles, nitrile rubber and polyamides. They can come from coatings on vehicles or buildings, from abrasion of tires or even shoe soles and many other common plastics. When they are whirled up and released into the atmosphere, they are transported by air currents, the scientists report. Snow then binds the particles and takes them to the surface of the earth.

Abstract (after expiration of the blocking period)

Abstract (study from Nature Geoscience)