The equivalent of 120 million plastic water bottles fell out of the sky onto 11 protected areas in the western United States in the form of plastic rain during the past year, claims a new study.
The study, published this month in the journal Science, focused on areas where you wouldn’t expect to find trash, such as the Grand Canyon.
Researchers spent 14 months collecting and analyzing rain and air samples. They used these to determine if microplastics had penetrated these pristine environments. These regions make up roughly 6% of the United States.
“I was just completely floored to see little brightly-colored pieces of plastic in nearly every single sample,” notes lead author Janice Brahney. “The number was just so large, it’s shocking.”
The results
Based on the team’s calculations, more than 1,000 metric tons of microplastic fall on these areas every year (and that’s a low estimate because the team’s equipment did not count white or clear particles).
This phenomenon is called “plastic rain” and it occurs when microplastics are swept into the air and water. Microplastics are defined as bits of plastic less than 5mm in length.
Up to 70% of the microplastics identified by Brahney’s team were microfibers, which come mainly from polyester clothing. Roughly 30% were microbeads, some of which were acrylic.
The team believes the microbeads came from industrial paint. The use of microbeads in the beauty industry was banned in the US in 2015.
“If that’s indeed the case, the paint industry may be in for the same kind of microbead reckoning that sullied the beauty industry,” notes Wired journalist Matt Simon. “Still, if one country bans microbeads in paints, the stuff could well blow in from a neighboring country.”
Should we be worried about plastic rain?
All told, plastic rain will be much more problematic than acid rain. That is because there is no way to remove the particles from the air, water, or soil.
“What makes plastic so useful…is what also makes it an alarming pollutant,” continues Simon. “Plastic never really goes away, instead breaking into even smaller bits that infiltrate even smaller corners of the planet.”
Microplastics eventually break down into nanoplastics. These are so tiny we could be breathing them in right now and not notice.
Scientists do not yet know the potential effects of nanoplastics on animal and human health. But we can assume they are negative. Microplastics disrupt the natural behavior of hermit crabs and to clog the stomachs of earthworms.
Brahney predicts microplastics will change the chemical makeup of soil. They could already be leading to the formation of unnatural clouds in the sky. To make matters worse, experts predict plastic waste will increase from 260 million tons per year to 460 million tons per year over the next decade.
Brahney’s study lines up with other studies in which microplastics have been discovered in remote areas such as the Arctic, the French Pyrenees, and deep-sea habitats.
