Plastic waste contributes to microplastics found in Earth's oceans, and new evidence suggests that the microscopic debris is found in clouds, as well.
More than 10 million tons of plastic enter the Earth's oceans annually, and the impacts of the waste are wide-ranging. It threatens marine life, ocean health, and human health and contributes to climate change. Plastic waste also leads to the creation of microplastics, the microscopic debris that is sourced from a range of synthetic materials, car tires and other everyday objects.
As plastic waste breaks down, the microplastics are released into the environment and wind up in oceans and even the clouds, according to a new study examining the path of airborne microplastics (AMPS). The study was led by Hiroshi Okochi, a professor at Japan's Waseda University, and a group of researchers.
Microplastics are known to cause an array of health issues in humans, potentially leading to cancer and damaging DNA. After learning the study's results, scientists fear that the microplastics could contaminate everything people eat and drink as the clouds dump plastic rain on the Earth. Plastic rain consists of millions of tiny microplastics falling from the sky.
Researchers collected cloud water from the summit and southeastern foothills of Mt. Fuji and the summit of Mt. Oyama to study the AMP presence in high-altitude clouds and the subsequent impacts on cloud formation and climate change. The research is believed to be the first of its kind to study the presence of microplastics in high-altitude clouds.
The study found that the AMPs in cloud water originated primarily from the ocean. Of the AMPs identified, there were nine different types of polymers and one type of rubber.
Would You Eat a Credit Card?
As the AMPs become an "essential component of clouds," they then can contaminate "nearly everything we eat and drink via 'plastic rainfall'", according to a report by Waseda University.
Research published in the journal Physics of Fluids in June revealed that humans breathe in large amounts of microplastics every week. The microplastics most often accumulate in the back of the throat and in the nasal cavities. The report found that humans inhale around 16.2 pieces of microplastics each hour, equating to a credit card's worth over the course of a week.
The presence of microplastics in the clouds also could impact the state of the climate.
"AMPs are degraded much faster in the upper atmosphere than on the ground due to strong ultraviolet radiation, and this degradation releases greenhouse gases and contributes to global warming," Okochi said. "As a result, the findings of this study can be used to account for the effects of AMPs in future global warming projections."
Newsweek reached out to Okochi by email for comment.
