Microplastics Invade Ancient Rock, And That's a Big Problem For Age Markers

Tiny fragments of plastic aren't only finding their way into animals, remote ice caps, oceans, and even the depths of our bodies. They're also seeping through layers of rock, making the emergence of plastics in the geological record a poor marker for the dawn of the human age.

In a new study, sediment samples from three different lakes in Latvia – Seksu, Pinku, and Usmas – were analyzed to see how deep microplastics had sunk. The results showed that smaller particles could travel deeper into the mud, reaching layers laid down before plastic production accelerated at the start of the 1950s.