ROCKY MOUNTAINS, COLORADO — New research from the U.S. Geological Survey has found microscopic plastic fibers present in rainwater from Rocky Mountain National Park in Colorado.

According to a study published by the U.S. Geological Survey, researchers involved in the study obtained rainwater samples from different altitudes from the Front Range of the Rocky Mountains. The samples were collected using buckets lined with plastic bags.

Scientists analyzed the rainwater samples with binocular microscope fitted with a digital camera.

Plastic was found in more than 90 percent of the sampled rainwater, according to the study.

Researchers discovered that the samples mostly contained plastic fibers in a wide range of colors such as red, silver, purple, green and yellow. They also found beads and shards in the rainwater samples.

Microplastics have previously been found in the depths of oceans, lakes and rivers across the U.S. and even the Pyrenees mountains, the Guardian reports.

According to the U.S. National Library of Medicine, microplastics are able to absorb and give off chemicals and pollutants. These may build up over time and persist in the environment.