Wind erosion of microplastics from urban soil surfaces

Plastic pollution is a growing concern worldwide, due to the potentially negative impacts on the environment and slow degradation of this material. When in the environment, plastic is fragmented into microplastics (<5mm), which have been found in all environmental compartments at different locations. Research focusing on terrestrial environments is still limited. The main sources of microplastic are linked to the urban environment, where people are concentrated. Microplastics can enter the soil via multiple pathways, but the transport processes contributing to variation of microplastics in the soils are poorly studied. This study investigates the transport of microplastics from the soil surface to the atmosphere through wind erosion, using a Portable In Situ Wind Erosion Laboratory (PI-SWERL). The PI-SWERL creates an increased wind shear near the ground producing wind erosion. The sediments emitted by the PI-SWERL were collected, as well as soil samples around each measurement place. Different urban spaces were tested in Coimbra city, Portugal: green parks; landfills; old dumps; industry places; sidewalks. Microplastics were extracted from the sediments collected from the PI-SWERL and the soil samples, and they were then identified using a stereo-microscope. The data is still under analysis. The results will show the relationship between the concentration of microplastics in soil and transported by wind erosion, which may clarify the role of different types of soil surface both as a sink and a source of diverse microplastic polymers. This data is valuable to understand the processes of microplastics in urban environments, as well as to validate microplastic transport models.