In a new study, researchers from the United States Geological Survey (USGS) discovered multicolored microplastic shards, beads and fibers in more than 90 percent of rainwater samples taken from across Colorado, including samples from locations more than two miles (3,000 meters) high in Rocky Mountain National Park.
Microplastics are very small pieces of plastic that pollute the environment. Microplastics aren’t a specific kind of plastic, but rather any type of plastic fragment that is less than 5 mm (.2 inches) in length.
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. It’s in the rain, it’s in the snow. It’s a part of our environment now.
They believe garbage dumped in the environment is the main source of microplastics, as well as plastic fibers released from synthetic clothes.
The researchers, who were studying nitrogen pollution at the time, collected rainwater samples from across Colorado and analyzed them using microscopes.
The growth in single-use consumer plastics has fueled a surge in plastic pollution across the globe. Other recent studies have turned up microplastics high in the remote Pyrenees Mountains, in the deepest part of the ocean, in Arctic sea ice, and in U.S. groundwater.
Researchers estimate that there are now 5.25 trillion pieces of ocean plastic debris, and a recent report estimated the quantity of plastic in the sea will triple by 2025.
Bottom line: A recent study has discovered microplastics in rainwater over the Rocky Mountains.
Eleanor Imster has helped write and edit EarthSky since 1995. She was an integral part of the award-winning EarthSky radio series almost since it began until it ended in 2013. Today, as Lead Editor at EarthSky.org, she helps present the science and nature stories and photos you enjoy. She also serves as one of the voices of EarthSky on social media platforms including Facebook, Twitter and G+. She and her husband live in Tennessee and have two grown sons.