Plastic dust rains on the Grand Canyon and other remote wildlands

Climate change. Deforestation. Intensive agriculture. Loss of wildlife habitats. Overfishing. These are all clear and present dangers to the health of the planet. Yet no less acute a crisis is plastic pollution.

Study after study has demonstrated the staggering amounts of plastic waste befouling both land and sea around the planet, and here comes yet another alarming revelation: as much as 1,000 tons of plastic dust rains down on national parks and remote areas of wilderness in the United States.

Put another way, around 132 pieces of microplastic land on every square meter of wilderness each day in this part of the U.S. In total, all that plastic dust a year adds up to 300 million plastic water bottles.

The scientist behind the study examined airborne microplastics in national parks and remote areas in the American West, including such relatively untouched swathes of wilderness as the Grand Canyon and Joshua Tree National Park. What she found came as a shock: these areas are dusted with tiny microplastics from clothes, carpets and other textiles that are borne by winds from urban areas near and far. Sometimes very far.

Janice Brahney, a biogeochemist at Utah State University who led the research, examined samples from 11 remote areas in the western part of United States and noticed brightly colored fragments under the microscope. “I realized that I was looking at deposition of plastics, which was really shocking,” she recalls.

She set about finding out the extent of the problem. Over the period of one year she ended up counting nearly 15,000 tiny pieces of microplastic, most of which were less than one-third the width of a human hair.

Nearly a third of the miniscule and brightly colored spheres she saw under the microscope were smaller than the plastic microbeads used in cosmetics and other personal care products. She realized that these tiny spheres were components of paints probably sent airborne during spray painting someplace else, perhaps hundreds or even thousands of kilometers away.

“We created something that won’t go away,” Brahney observes. “It’s now circulating around the globe.”

That certainly seems to be the case. A study last year found that even remote spots high atop the French Pyrenees are covered in microplastics where upwards of 365 tiny particles cover every square meter in an area that was examined by researchers at an elevation of around 3 kilometers.

According to Brahney, most of the fine plastic dust that “rains” down in places like the Grand Canyon originates in distant locations and is carried by winds at high altitudes. Three-quarters of the tiny plastic particles are deposited during dry weather rather than actual rain.

These tiny plastic particles, she says, can travel for thousands of kilometers this way.