Feature Health & Medicine

Microplastics are in our bodies. Here’s why we don’t know the health risks

There are big, open scientific questions about levels of exposure and toxicity

A photo of a city street with over large bits of microplastics overlaying the image.

Microplastics are in the air we breathe and have turned up in lung tissue. But the potential health effects are far from clear.

LISA SHEEHAN

By Anne Pinto-Rodrigues

Tiny particles of plastic have been found everywhere — from the deepest place on the planet, the Mariana Trench, to the top of Mount Everest. And now more and more studies are finding that microplastics, defined as plastic pieces less than 5 millimeters across, are also in our bodies.