Microplastics are known to be ubiquitous contaminants and although our knowledge of them is increasing, we know little about the basic transport processes of microplastics in the aquatic environment. Theoretical principles from natural sediment transport are often used to describe microplastic transport, but do they provide sufficiently accurate results for this new "artificial sediment"?
In my dissertation at RWTH Aachen University, I compared the behaviour of microplastics in the fluvial environment with theoretical calculations from classical sediment transport using physical model experiments. The transport process was divided into resuspension, sedimentation and rising as well as infiltration into the river bed. Furthermore, I paid special attention to the effects of microplastic particle properties such as density, diameter and shape on the transport mechanisms.
At WUR I will now continue to work on the transport of microplastics in the aquatic environment. This involves physical model experiments in the Kraijenhoff van de Leur Laboratory for Water and Sediment Dynamics as well as environmental sampling and hydronumerical modelling. At the moment, we have two major microplastic project focusing on:
- The impact of turbulence on the vertical distribution of microplastics and their transport in rivers (PhD project of Hadeel Al-Zawaidah)
- The impact of biofouling on the transport of fluvial microplastics (in collaboration with the Aquatic Ecology and Water Quality Group at WUR)
We still know far too little about the fundamental transport processes of microplastics, yet these are important basics to better understand the distribution and accumulation of microplastics in the environment and ultimately to take measures to reduce environmental pollution with plastics.