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Microplastics are blowing in the windA remote spot in the French Pyrenees is getting as many microplastics per day as downtown ParisPlastic pollution from cities doesn’t always stay in cities. Tiny bits can migrate on the wind, a new study finds. This trash can end up on a remote mountain at least 95 kilometers (59 miles) away. It’s the first proof that microplastics — tiny bits of plastic trash 5 millimeters (0.2 inch) or smaller — are traveling long distances by air.And we’re not talking about just a little plastic. The new findings suggest the rain of plastic bits in remote places may rival that in some large cities.Researchers from EcoLab in Castanet-Tolosan, France, wanted to know if microplastics tend to travel on the winds. To find out, they set up two types of large containers. Each collected microplastics falling out of the air at the Bernadouze weather station. It sits in the Pyrenees Mountains between France and Spain. Scientists visited the site roughly once a month for five months. Each time, they took out all the particles that had fallen from the sky. Then they separated out the plastic bits, identified them by type and tallied?the totals.And they found plenty.An average of HYPERLINK "" \t "_blank" 365 microplastic particles per square meter (10.7 square feet) per day landed at the site. This means that plastic lands high in the mountains at a rate “similar to what’s happening in Paris,” says Deonie Allen. She’s an atmospheric and environmental scientist at EcoLab. Her group shared its findings April 15 in Nature Geoscience.The mountain fallout is somewhat different.The mountaintop may have been getting as many plastic bits as Paris. But the size and types of those bits was not the same. Previous studies had looked at plastics falling from the air in Paris and Dongguan, China. In both cities, most particles were slender fibers larger than about 100 micrometers. That’s a little thicker than a human hair. The fibers were made of the plastics polypropylene (Pah-lee-PRO-puh-leen) or polyethylene terephthalate (Pah-lee-ETH-eh-leen Tair-eh-THAAL-ayt), also known as PET. Clothing and other fabrics often shed these fibers.At the mountain site, most plastic bits were smaller than 25 micrometers. This plastic pollution wasn’t from fabric. Instead, it consisted mostly of polystyrene and polyethylene. These plastics are found in many packing materials. Polystyrene, for example, is commonly known as Styrofoam.Polystyrene can be degraded by weather. It also can be broken down by ultraviolet waves from the sun — waves invisible to the human eye. The resulting?small bits can easily be carried on the wind, the researchers say. Winds and brief bursts of intense rain or snow were linked, in fact, with more of these plastics raining down on the mountain.The study couldn’t definitely identify the source of the plastics. Instead the scientists used a computer program. They modeled where the wind was coming from and how fast it was blowing when they collected the trash. The plastics traveled at least 95 kilometers (59 miles) to reach the site, the computer model showed. In fact, Allen says, it’s likely that the plastics came from farther away than that. He points out that there are no big cities within 95 kilometers that would have shed those plastic bits.?The study confirms that microplastics are everywhere in the environment, says Johnny Gaspéri. He’s an environmental scientist at the Université Paris-Est Créteil. He was not involved in the study. ??So far, the scientists have studied only one mountain site. They want to collect more samples from other remote locations. “It’s not just local pollution, or something only happening in cities,” says study coauthor Steve Allen. He is an atmospheric and environmental scientist at EcoLab. Plastic isn’t staying where people put it. “Invisible pollution is transporting its way around the world.”Home, plastic homeSome ocean life is moving into floating piles of plastic trashWe live in an increasingly plastic world. Much of this plastic does not degrade easily. That allows it to pollute the environment. There, a great deal of trashed plastic will break into tinier bits that eventually wash into the ocean. Recently, this debris has begun creating new homes for microbes, research now shows.Plastic trash in the ocean hosts a diverse world of one-celled organisms, observe Erik Zettler, Tracy Mincer and Linda Amaral-Zettler. The three work at the Woods Hole Oceanographic Institution and Marine Biological Laboratory, both in Woods Hole, Mass. They have given a new name to microbes and their plastic homes: the plastisphere (PLAS ti sfeer).Microbes in the plastisphere tend to differ from those in the open water, Zettler’s team finds. In fact, the researchers conclude, “that plastic serves as a novel ecological habitat in the open ocean.” They shared their new data July 2 in Environmental Science & Technology.There’s a lot of trashed plastic to be colonized by germs. People began widely using plastics only a little more than 60 years ago. Since then, the production of plastics has only increased. Each year, manufacturers now make another 245 million tons of plastic. That’s about 35 kilograms (77 pounds) for each man, woman and child on the planet, Zettler’s team observes. It’s also close to the weight of all people alive today.This plastic isn’t evenly distributed throughout the ocean. Much of it collects at a few distinct sites known as gyres (JI erz). That’s where the Woods Hole researchers sampled for microbes. They netted small pieces of plastic and then analyzed these floating bits of trash for microbes. They focused on bacteria.The researchers also sampled nearby seawater from outside a gyre.Some bacteria were rod-shaped. Others were round. And some one-celled predatory microbes were shaped like a stalk with grasping, threadlike arms. Many microbes look pretty similar. So the biologists separated the germs into types by looking at their DNA. This molecule contains the genes that make one species distinct from another.Many ocean microbes have not yet been formally identified by species (or DNA details). So most germs living in the plastic debris could only be classified as belonging to some basic type. The researchers found that a single tiny bit of plastic might host more than 1,000 different types of one-celled microbes.Much of the ocean plastic belonged to two common types: polyethylene and polypropylene. The first is lightweight but tough and has a fairly slick surface. The second is stiffer and more scratch resistant. Roughly 30 percent of the microbes collected were found on both types of plastic. The remainder of the collected germs inhabited just one or the other type of plastic, not both. One suspected reason: Some microbes appeared to be eating away at the plastic, and not all may have an appetite for the same entrée.Another potential reason for the microbes’ pickiness: Some like to hang out with certain other types. Together, they form slimy communities known as biofilms.Vibrio bacteria were among those germs identified on ocean plastic. Some Vibrio bacteria can cause disease (such as cholera) in animals, including people. This suggests that ocean plastics could help transport harmful germs, the scientists note. And because plastic lasts longer than plant- and animal-based materials, it may ferry harmful germs thousands of kilometers from coasts. Sea turtles, birds and fish in the open ocean may mistake the plastic for food bits and become infected by the germs they carry.One surprise from the study: Some of the microbes found on the plastic debris are normally only seen floating in the open ocean. Scientists thought these germs would not stick or attach to things like sediment or these plastic bits — until now.What really makes plastic debris in the ocean dangerous is the poisons it may ferry, says Anthony Andrady. A plastics specialist at North Carolina State University in Raleigh, he did not work on the new study. “In the ocean,” he explains, “plastics act like a sponge.” That means they can absorb and concentrate certain toxic pollutants, including pesticides.Indeed, several years ago, Jo?o Frias collected bits of polystyrene (another type of plastic) and polypropylene from beach sand. Frias works at the Institute of Marine Research at the New University of Lisbon in Caparica, Portugal. “Every sample was contaminated,” he recalls. The plastic bits hosted a range of hard-to-degrade pollutants — many of them harmful. These included the long-banned pesticide DDT and polychlorinated biphenyls (also known as PCBs). Chemical wastes produced by sooty fossil-fuel burning were also found.Animals, including people, do not naturally produce the chemicals needed to digest plastics. So most plastics should not, on their own, be very toxic to sea life, says Andrady. The problem, he says, will likely come from any pollutants that taint plastics at sea.Zettler’s team now adds another warning: Harmful germs may pose another major threat to animals that mistake plastic for food.Selected Vocabbiofilm A gooey community of different types of microbes that essentially glues itself to some solid surface. Living in a biofilm is one way microbes protect themselves from stressful agents (such as poisons) in their environment.deposition?????(in chemistry) When atoms settle or are deposited onto a separate material (which is generally known as a substrate).ubiquitous?????(n. ubiquity) A term for something that is omnipresent — found essentially everywhere. ................
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