The discovery of the microplastics was a surprise. A research team was analyzing rainwater samples from national parks and wilderness areas across Colorado, as part of a pilot study on a new type of field equipment. They were shocked to find that the samples contained microplastics – plastic fragments less than 5 mm (.2 inch) in length – including a rainbow of plastic fibers, as well as beads and shards.
Utah State University assistant professor Janice Brahney is lead author of the study, published June 12, 2020, in Science. Brahney said in a statement:
We were shocked at the estimated deposition rates and kept trying to figure out where our calculations went wrong. We then confirmed through 32 different particle scans that roughly 4% of the atmospheric particles analyzed from these remote locations were synthetic polymers.