By now, most of us have heard of the immense amount of plastic that has reached the world’s oceans. However, a new study published in the journal Science has found that microplastics—defined as less than 5mm in length—don’t just end up in the sea. These small particles can not only travel through the air, but they can get carried away by the rain onto far-flung and otherwise pristine land.

These particles come from larger discarded pieces of plastic, or they shed from clothing made of synthetic material like polyester. Additionally, these bits can come in the form of microbeads, small polyethylene plastic pieces added to beauty and cleaning products as exfoliators and scrubbers.

Scientists have also started to distinguish these small particles from even tinier pieces of plastic. Dubbed nanoplastics, these snippets are less than 100 micrometers in length or a tenth of a millimeter, and they present a challenge to researchers, as you can’t measure them with conventional instruments. The extent of this plastic distribution in the Earth’s atmosphere is also unknown, as well as its impact on the environment.