Microplastics are microscopic pieces of plastic that are making their way into everything from drinking water to marine life, and now the U.S. Geological Survey says they’re falling from the sky when it rains, according to a new report.

Scientists collected samples of rainwater from a variety of locations throughout Colorado, some from urban areas and others from remote areas, and found plastic in more than 90 percent of the samples.

Most of the plastic which was found in the samples consisted of fibers which needed to be magnified 20 to 40 times to be visible. Blue was the most common color of these particles, followed by red, silver, purple, green and yellow.

Atmospheric wet deposition samples were collected at eight different sites, most of which were along the Denver and Boulder urban corridor. Two of the sites were more remote, one of which was located at Loch Vale in Rocky Mountain National Park.