Microplastic particles equivalent to as many as 300m plastic water bottles are raining down on the Grand Canyon, Joshua Tree and other US national parks, researchers have found.
In a survey of 11 remote western locations, also including the Great Basin and Craters of the Moon national parks, researchers discovered more than 1,000 tons of microplastic particles that had traveled through the atmosphere like rain or water particles.
Most microplastics are fragments from larger pieces of plastic. Since plastics aren’t biodegradable, plastics that end up in waste piles or landfills break down into microparticles and make their way through the Earth’s atmosphere, soil and water systems.
Janice Brahney, lead researcher and professor of watershed sciences at Utah State University, calls this process “plastic spiraling” – and some microplastics have been traveling through natural systems for a long periods.
“Plastics could be deposited, readmitted to the atmosphere, transported for some time, deposited and maybe picked up again,” Brahney said. “And who knows how many times and who knows how far they’ve travelled?”