Researchers at the University of Vienna have determined that land releases more than 20 times as many microplastic particles into the atmosphere as the oceans, challenging prior assumptions. Their study, published in Nature, used global measurements to correct overestimated emission models. The findings highlight land as the dominant source, though uncertainties persist.
Scientists from the Department of Meteorology and Geophysics at the University of Vienna analyzed 2,782 atmospheric microplastic measurements worldwide. They compared these observations with a transport model incorporating various emission estimates, revealing that previous models overestimated airborne microplastics by orders of magnitude, particularly from land sources. By recalibrating the model, the team refined emissions data for both land and ocean origins, as detailed in their paper published in Nature this year (DOI: 10.1038/s41586-025-09998-6). Materials were provided by the University of Vienna ahead of publication. Lead author Andreas Stohl stated, 'The now scaled emission estimates show that over 20 times more microplastic particles are emitted on land than from the ocean.' First author Ioanna Evangelou added, 'However, the emitted mass is actually higher over the ocean than over land, which is due to the larger average size of oceanic particles.' The research underscores how microplastics from sources like tire abrasion and textiles on land dominate atmospheric transport, spreading pollution globally to remote areas. Stohl emphasized ongoing challenges: 'However, the data situation is still not satisfactory, and there are still major uncertainties. More measurements are needed so that we know how much microplastic comes from traffic and how much from other sources.' The study calls for better data on particle size distributions to improve future estimates.