Microplastics are small plastic particles less than five millimeters in size consisting of synthetic organic compounds. Recent studies document that tire wear significantly contributes to the flux of microplastics into the environment. However, data on tire wear particle pollution of surface waters as well as on their concentration and fate are rare. Emissions and pathways depend on local factors like road type or sewage systems. The relative contribution of tire wear and tear to the total global amount of plastics ending up in our oceans is estimated to be 5-10%.

For this study, we select highly frequented roads throughout Freiburg for sampling tire abrasion in runoff after precipitation events. We would like to determine the size, shape and volume of the tire wear particles and estimate their contribution and pathways into the Dreisam River. The project is in cooperation with the particle lab of the DWD (Freiburg).

Tire wear particle sampled in the Dreisam (photo: Judith Johannsen)

Lab and field work, statistics

Natalie Orlowski: natalie.orlowski@hydrology.uni-freiburg.de; Tel. +49 (0)761 / 203-9283

In cooperation with Volker Dietze (DWD Freiburg): volker.dietze@dwd.de

English/German

• Horton, A. A. and Dixon, S. J.: Microplastics: An introduction to environmental transport processes, Wiley Interdisciplinary Reviews: Water, 5(2), e1268, doi:10.1002/wat2.1268, 2018.
• Kole, P. J., Löhr, A. J., Van Belleghem, F. G. A. J. and Ragas, A. M. J.: Wear and Tear of Tyres: A Stealthy Source of Microplastics in the Environment, International Journal of Environmental Research and Public Health, 14(10), 1265, doi:10.3390/ijerph14101265, 2017.
• Sommer, F., Dietze, V., Baum, A., Sauer, J., Gilge, S., Maschowski, C. and Gieré, R.: Tire Abrasion as a Major Source of Microplastics in the Environment, Aerosol and Air Quality Research, 18(8), 2014–2028, doi:10.4209/aaqr.2018.03.0099, 2018.