Discovery raises new questions about the amount of plastic waste permeating the air, water, and soil virtually everywhere on Earth
Plastic was the furthest thing from Gregory Wetherbee’s mind when he began analyzing rainwater samples collected from the Rocky Mountains. “I guess I expected to see mostly soil and mineral particles,” said the US Geological Survey researcher. Instead, he found multicolored microscopic plastic fibers.
The discovery, published in a recent study (pdf) titled “It is raining plastic”, raises new questions about the amount of plastic waste permeating the air, water, and soil virtually everywhere on Earth.
“I think the most important result that we can share with the American public is that there’s more plastic out there than meets the eye,” said Wetherbee. “It’s in the rain, it’s in the snow. It’s a part of our environment now.”
Rainwater samples collected across Colorado and analyzed under a microscope contained a rainbow of plastic fibers, as well as beads and shards. The findings shocked Wetherbee, who had been collecting the samples in order to study nitrogen pollution.
“My results are purely accidental,” he said, though they are consistent with another recent study that found microplastics in the Pyrenees, suggesting plastic particles could travel with the wind for hundreds, if not thousands, of kilometers. Other studies have turned up microplastics in the deepest reaches of the ocean, in UK lakes and rivers and in US groundwater.
A major contributor is trash, said Sherri Mason, a microplastics researcher and sustainability coordinator at Penn State Behrend. More than 90% of plastic waste is not recycled, and as it slowly degrades it breaks into smaller and smaller pieces. “Plastic fibers also break off your clothes every time you wash them,” Mason said, and plastic particles are byproducts of a variety of industrial processes.