The winds may be blowing Microplastics around the world

On top The French Pyrenees, not far from the border with Spain, is a virtually pristine clearing, home to snow and a weather station, but mostly feet on foot of snow. The nearest road closes in winter. The most important city within the 60 miles has only 9,000 inhabitants.

However, if you look closely at the landscape, you will see that the place is covered in plastic. Between November 2017 and March 2018, the researchers collected water from the collectors of the weather station and searched for microplastics (just under a fifth of an inch) and discovered that 365 particles land on each square meter each day. The fountain? Likely winds that blow from big cities like Barcelona, ​​100 miles to the south.

With the discovery, researchers have revealed a new horror of plastic pollution. Scientists already knew that microplastics can float in the air of big cities like Paris and Dongguan, China, but nobody has shown how far these things can travel. This work was a short-term pilot study that requires more research by other researchers, but the implications are striking: for supposedly pristine environments around the world, for ecosystems and for human health.

Allen, et al., Nature Geoscience

The central problem when it comes to plastic, as we have all heard, is that things take a thousand years to decompose, meanwhile, they bounce back into the environment. And when something like a plastic bottle breaks down, it breaks away from small fragments of itself, microplastics that then make their way into organisms. This is a particular problem at sea, which has been fairly well studied: a survey found that mussels sampled throughout the United Kingdom everyone I had microplastics in them.

Less understood at this point is how different types of plastic (researchers found a range in their samples, from polystyrene to polyethylene to polypropylene) travel through the atmosphere differently depending on their material properties. It is also little known how the shape of a microplastic, whether a film or fiber or a fragment, affects its movement. I could badume that a movie with more surface area would travel farther than a fragment, but that has simply not been proven.

"This is one of the challenges to move forward, trying to model how these 3D plastics move in the air, so we can find out where they come from," says environmental scientist Deonie Allen of the EcoLab, part of the National Research Center for France, co-author of a new article in Geosciences of nature.

To some extent, it may not be too surprising that researchers have found microplastics here in the Pyrenees, because in their sampling they found another important clue: a fine orange powder. This probably occurred in the Sahara, a phenomenon that this monitoring station has recorded for more than a century. (More incredible still, the dust of the Sahara also crosses the Atlantic to fertilize the tropical rainforests of South America).

"The winds do not make a distinction between the type of particles," says marine geologist Michèlle van der Does, who has studied the long-range transport of dust particles, but did not participate in this new work. "These plastic particles are much larger than the dust particles we found, although we also found these giant dust particles. But their density is much lower, so they are also easier to transport over long distances. "

Another consideration is the unique nature of the plastic decomposition. As the microplastics break, theoretically their properties would change. So a single fiber could break into two fibers, creating new pieces with a new aerodynamics. As they break down, the microplastics turn into something even more sinister: the nano-plastic, a piece smaller than a micron or a millionth of a meter.

These tiny fragments of plastic, which fade, can reach almost anywhere, even through the tissues of an organism, as researchers discovered when they introduced nanoplastics into scallops. "What they showed was that within 6 hours these nanoparticles march through the animal," says study co-author Steve Allen, an environmental pollution scientist at the University of Strathclyde and EcoLab (and wife of Deonie Allen). "They are in all parts of the animal in 6 hours."

It's not just the plastic so organisms have to worry. "We know that these plastics absorb all the chemicals that pbad through the environment, such as pesticides," says Steve Allen. "We also know that they have heavy metals attached to them, so if these particles go to your lungs and carry those chemicals there, we do not know what's going to happen there either."

Even more worrying: nanoplastics are very similar to the nanoparticles used in medicine to administer drugs in the human body. "So they can cross the blood-brain barrier potentially in the same way but carrying their toxins," says Deonie Allen. "And this is really worrying." To be clear, however, this idea has not been backed up with data.

The researchers to haveHowever, he explored another worrying feature of plastic in the oceans. "In some ecosystems like coral reefs, plastics work as disease vectors," says Luiz Rocha, fish curator at the California Academy of Sciences, who was not involved in the study. "Then, a piece of plastic is like a small Petri dish for all kinds of bacteria, including pathogens. As they move through the reef, they touch a coral and another coral and transmit the disease. "

If microplastics could act as vectors of diseases on earth, it is another question that demands more investigation. But it is important to bear in mind that the microplastic and nano-plastic problem is not a sea-land dichotomy. The effect of plastic on marine creatures has been much more studied than its effects on terrestrial creatures like us, but there is also a bit of interaction between the two environments.

Take clothes, for example. Washing clothes such as yoga pants and fleeces can release hundreds of thousands of synthetic fibers per wash cycle into the environment. "They are not completely eliminated with the filters, they are not completely eliminated with the wastewater treatment plants," says the badytical chemist at the University of Aveiro, João Pinto da Costa, who studied plastics in the environment but did not participate. new research The fibers end up in rivers and seas, but also in sediments, where they dry up and are picked up by the wind. "Also, when you're just drying your clothes, it's easy to imagine that many fibers will be transported in the wind."

This presents us with a surprisingly complex problem. Undoubtedly, plastics have made the world a safer and healthier place: imagine what medicine would be like without technology. But the scale with which plastics are contaminating this planet and their ways of life is increasingly clear. Even if your country decides to ban all single-use plastic bags, your neighbors could continue to produce them and, if this developing model of airborne contamination is true, the resulting microplastics could explode their way. In that sense, it is not so different from climate change: either we all approach it together or we risk getting nowhere.

"It means it's everyone's problem," says Deonie Allen. "But it also means that if you think about the amount of pollution that exists in places like China, where they're wearing masks, that's something we could face because we're not handling our plastic." That is very scary and could motivate people to do something. "

It is worth noting again that this was a small pilot study. But it is also worth noting that part of the reason for this was that the researchers were so alarmed by the findings, that they wanted to spread the news quickly so that the scientific community could investigate how microplastics are blowing around the Earth.

"We're breathing it," says Deonie Allen. "Look, people, do not just look down."

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