How much microplastic are we actually breathing in? Here's what we do and still don't know

You've already inhaled thousands of microscopic particles today.

Some will be dust, pollen or soot, and some will be plastic.

Microplastics—tiny fragments shed from clothes, tires or packaging—have been found pretty much everywhere.

They're in oceans, soils, wildlife, remote mountaintops, deep-sea trenches and the atmosphere. ...