A new international study led by scientists at Utah State University shows that 84% of microplastics come from roads, especially suburban roads. The small pieces that fall off the tires are “picked up” by the wind and transported to them through atmospheric circulation. Everywhere.
Ubiquitous spread Microplasticity Considered to be one of the most serious threatssurroundings this is ours salute.These small pieces of plastic waste (diameter equal to or less than 5mm) Has now entered our Food chain And, according to a recent study by scientists from Newcastle University and WWF, we take it every week without realizing it. 5 grams. This means that every year it seems that we are eating a 250g piece of pasta made entirely of plastic, and the health effects have not yet been determined. Recently, a study by Arizona State University first discovered nanoplastics and microplastics in human tissues and organs, and Italian colleagues at Fatebenefratelli Hospital in Rome have discovered microplastics in the placenta. It is estimated that in the most remote areas of the United States, more than one thousand tons of rain fall every year, from the polar regions to the depths. Therefore, we are actually overwhelmed by plastic.A new study now shows its origin Scattered in the atmosphere: The vast majority of them (up to 84%) come from street, From normal wear and tear Tires And from traffic Projected on aria.
Determine the main source of microplastics are roads (especially those roads) suburb) Is an international research team led by scientists from Utah State University. He works closely with colleagues in the Department of Earth and Atmospheric Sciences at Cornell University and the Department of Climate Studies at Cornell University. The National Laboratory of the Finnish Meteorological Institute in Helsinki in the Northwest Pacific, the Graduate School of Environmental Studies at Nagoya University (Japan) and other research centers around the world. Scientists led by Professor Janice Brahney, a lecturer in the Logan Watershed Science Department, came to their conclusions after collecting them. Hundreds of samples Between December 2017 and January 2019, microplastics were collected from 11 sites in the western United States.
As shown in the figure, through the analysis of the samples, it is determined that most of them come from the road and normal tire wear. Some people would think that busy urban roads are the main source of these microplastics, but as the authors of the study explained, they are outside the city. There are two reasons.First is in City street Cars are usually slower, so Turbulence The resulting motion is usually not enough to cause the debris falling off the wheels to rise towards the higher atmosphere.Secondly I palace They will stop this turbulence and wind and hold the microplastics in place. On the major arteries connecting cities and highways, when the wind blows over them, cars will travel at high speeds, and microplastics are easily lifted and thrown into the air, thus entering the atmospheric circulation.
other 11% Brahney and colleagues explained that the source of microplastics comes from Wave way And give it Splashing sea, Is now full of microplastics. Small fragments (derived from the destruction of large waste) reach the surface, and when waves hit rocks or are stirred by wind, they cause microplastics to rise, reach the atmosphere and be transported everywhere.This Five percent originate from Agricultural soil, And the other 0.4% are from other people.Scientists have input these data into a complex mathematical modelBased on this, it has been determined that microplastics can remain in the atmosphere for several hours Up to a week. This is enough time to allow it to be transported by wind to other regions, other states, and in some cases even other continents. This is how the Arctic and Antarctica are polluted. Of course, there is no direct discharge of microplastics.
We have been producing since the beginning of the 20th century 10 billion tons of plastic For scientists, it is essential to understand the fate of all substances that are dispersed (especially in the ocean) and converted into microplastics, and to understand their impact on different ecosystems and ultimately our health. The details of the study”The atmospheric branch that limits the plastic cycle“Published in the scientific journal PNAS.