In toothpaste, clothing, in the oceans, and even the atmosphere: plastic surrounds us. Instead of dissolving, it fragments into ever-smaller particles. Researchers can now detect so-called microplastics in nearly every corner of our Earth. A research team from the University of Vienna has now calculated that the global amount of microplastics could be far lower than previously suspected.
The researchers report in the scientific journal Nature that microplastics in the atmosphere, according to their models, could be between 100 and 10,000 times lower than what scientific studies have estimated so far. Microplastics are typically counted at sizes of one to five micrometers. A micrometer is one thousandth of a millimeter.
„The study shows that the global microplastic concentrations in the atmosphere are lower than previously assumed,” says Ankush Kaushik, a research fellow at the Leibniz Institute for Tropospheric Research in Leipzig.
The team led by the principal author Ioanna Evangelou drew on measurements from previous studies dating from 2014 to 2024 and from more than 280 locations worldwide. For their investigation, the researchers used concentration and deposition rates of microplastics in the atmosphere. In the next step, they simulated various models to compare the values on a global scale.
Nevertheless: enormous amounts of microplastics – and nanoplastics
The air over land was, in median, twenty times more enriched with microplastics than over the sea. On land, the plastic particles are mainly produced by industry and the tire wear of cars. The team estimates that from land about 610 quadrillion microplastic particles per year enter the atmosphere. In short: enormous. Nevertheless, this result is well below the amounts reported by previous studies.
Ankush Kaushik, who also researches microplastics at the Leibniz Institute for Tropospheric Research but was not involved in the current study, says: “The results should be communicated with caution, because lower global concentrations do not mean that microplastics in the atmosphere are unimportant.” To better understand the extent, standardized measurement methods, evenly distributed measurement sites, and detection of even smaller plastic particles are required.
The entire globe is affected by plastic pollution in all its forms, colors, and compositions. Even in the most remote ecosystems such as the deep sea, microplastics have already been detected.
That previous measurements, according to the Vienna study, have overestimated microplastics in the atmosphere mainly shows that research methods still need to become more precise. In China, researchers studied samples with an electron microscope. In doing so, they found a higher concentration of even tinier nanoplastics than previously.
