Better keep that mask handy post-Covid. We’ve all experienced that sunny day inside our homes or building when we see that ray of light shining through, illuminating the dust in the air. Turns out that most of this dust is actually composed of microplastics, tiny airborne fibers small enough to penetrate the human body. Not only are these materials foreign bodies in and of themselves, these microplastics carry pesticides, heavy metals and other chemicals straight into our lungs.
A recent 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 – even as far away as the Sahara Desert. And if you think you can simply close the windows and protect yourself, think again. 62 percent of our clothes are made from plastics including from fabrics like lycra, nylon and polyester. Microscopic pieces of our clothes get detached and released in the air inside and outside our residences through ordinary wear and tear and laundering. Studies have found microplastics in our food, glasses of beer, and cups of tea and coffee.
The outdoors provides no respite from this exposure, in large part because our cars are spewing out these microplastics as well. Rubber tires contain synthetic elastomers and plastic fibers to improve stability while brakes are a mixture of plastic and metal. Fragments of these materials erode with friction whenever rubber meets the road or you pump the brakes, sending these pieces into the air, gutters and storm drains. Recent modeling has demonstrated that, given their small size and light weight allowing them to be lofted high and far in the air, microplastics pour from the cities of Europe, Asia, and the Americas, and settle out in such far flung regions as the Arctic, Greenland, and of course the world’s oceans. Current calculations show that, 52,000 tons of the smallest particles end up in the sea each year, and 20,000 tons end up in remote snowy and icy regions. Meanwhile, field research last year found that microplastics in a single liter of Arctic snow, contained a staggering concentration of around 14,000 plastic particles, while samples from the floor of the Arctic Ocean contained 13,000 microplastic particles per kilogram of sediment. In addition to the human health issues, researchers are also concerned that the concentration of microplastics in the Arctic are darkening the snow, thereby limiting the albedo reflection effect that helps slow global warming.
While there seems to be no global solution to this problem, scientists offer local solutions that we can implement in our daily lives to reduce our exposure, including using less plastic, buying fewer clothes and opting for natural fibers when we do. Air and washing machine filtration systems may also help. But for now, it appears that this phenomenon is another problem issue we are going to have to live with for the immediate future.