An anonymous reader quotes a report from The Guardian: 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 U.S. 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. 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 U.S. groundwater.