(Scientific American)
Atmospheric currents are transporting plastic pollution into remote, pristine areas, showing the global nature of the problem.
Amid the rugged peaks of the Vicdessos region of the French Pyrenees, the only visible signs of a human presence are a smattering of villages and the odd hiker or skier; it is considered a pristine environment. But even here, scientists have detected tiny pieces of plastic falling out of the air like artificial dust.
A first-of-its-kind study finds these particles have blown in on the wind from at least 100 kilometers away and likely much farther. This is a clear indication that atmospheric transport is yet another way plastic pollution is being distributed around the planet, even to remote areas. “And it suggests that this is a far bigger problem than we have currently thought about,” says study co-author Deonie Allen, of the École Nationale Supérieure Agronomique de Toulouse (ENSAT).
The study, published Monday in Nature Geoscience, is one of only a handful that have attempted to measure how much plastic is falling from the atmosphere. It marks the first wave in what is likely to be a flood of such studies in the coming years, in an effort to fill in the picture of how microplastics move around the environment and how humans might be exposed to them.
“NOBODY HAD LOOKED UP”
Microplastics are tiny pieces that break off larger plastic items (such as bottles and bags) as they degrade in the environment, as well as the fibers that slough off synthetic fabrics. They come in a wide range of sizes—from a grain of rice down to a virus—and are made up of a complex variety of polymers and added chemicals.
Most research to detect microplastics in the environment has been done in the ocean, where they were first noticed, but scientists have slowly realized they are also present in freshwater systems, soil and the atmosphere. The first study to measure plastic fallout from the atmosphere—conducted in Paris—was published only in 2015. The recent attention to the issue means that there are only a handful of measurements of airborne plastic, and little sense of how the numbers might vary from place to place, depending on weather conditions and where the material is ultimately coming from.
Allen and her colleagues knew microplastics had been found in rivers and sediments in the Pyrenees, but no one had determined the sources. The bulk could not have come from local sources because of the small human population and limited industrial activity, so Allen was struck by a key question: “Why haven’t we looked up?”
To find out the answer please continue reading on Scientific American.
From Scientific American, by Andrea Thompson on April 15, 2019