Most Dust Motes In Our Homes Are Unsafe Microplastics, And The Saharan Dust Cloud May Bring More

It’s a good thing you’re wearing your mask.
Most of the dust motes floating in homes are plastic microfibers, scientists say, that have no business in our lungs.
“If you think, for example, of a sunny day, and you’re inside your house,” said Sarah-Jeanne Royer, a biogeochemist and research fellow at the Scripps Institution of Oceanography. “You’re looking to the window and you see this ray of light shining inside of your house, you will see all these small particles and dust floating. Well, most of this dust is actually composed of microfibers. And we find these microfibers everywhere.”
Everywhere is not the best place for airborne plastics to be.
“We’re not supposed to breathe in this material,” Steve Allen, a microplastics researcher at the University of Strathclyde in Scotland recently told Scientific American.
They “carry all sorts of pesticides, heavy metals and all the other chemicals that we've made over time,” he said. “They're going to carry them directly into our lungs.”
Allen and a team of colleagues captured microplastics over a period of five months at a meteorological station about 4,500 feet above sea level in France’s Pyrenees mountains. They studied wind patterns to try to determine the source of the plastics, and determined they came from a dry place more than 60 miles away. Because they were accompanied by orange quartz-like fine dust, the most likely suspect was the Sahara.
A more recent blockbuster study of plastics in Western U.S. natural parks found that 98 percent of samples contained microplastics and that 70 percent of them were small enough to have arrived from distant reaches of the globe. The study relies on prior work that analyzed dust distribution from North African sources including the Sahara.
The Saharan dust cloud now darkening the U.S. Gulf Coast has made headlines for potential impacts on hurricane season and lung diseases like asthma, and on its potential for complicating coronavirus infection. Its microplastic content remains largely unexplored.
Closing the windows won’t eliminate microplastics raining from the cloud, because many of the fibers originate in our homes.
“We have to remember that 62 percent of our clothes are made from plastics,” Royer said during the EarthxOceans conference this month, citing lycra, nylon, polyester as popular plastic fabrics. “While wearing these clothes, microscopic pieces of them get detached. These are called microfibers. They get released in the air, inside, outside, in your house.
“We breathe them, we eat them when we are having food, we also find them in our glass of beer, in our cup of tea or coffee.”
The problem sounds overwhelming, but Royer insists there are solutions: use less plastic. Buy fewer clothes, and when we must buy clothes, opt for natural fibers. For those plastic clothes we’re unwilling to give up, equip our washers with a filter fine enough to capture microplastics to keep them from entering the environment—and eventually, our bodies.