http://www.sciencemag.org/news/2019/04/airborne-microplastics-found-atop-france-s-remote-pyrenees-mountains

Microscopic fragments of plastic have invaded the farthest reaches of the sea, from the depths of the Mariana Trench to the freezing waters off Antarctica. Now, researchers have found that such microplastics have polluted the Pyrenees mountains, expanding plastic’s dominion to previously unknown heights.

Prior studies have shown that microplastics, which can be ingested and inhaled by humans—and which may lead to reproductive issues in some marine mollusks—can rise up into the atmosphere and drop back to solid ground in the cities they come from. But scientists thought these plastics couldn’t travel very far from their urban sources.