
PhD defence
Environmental microplastics: properties, exposure and risk
Summary
Microplastics, small plastic particles, are ubiquitous in the environment. However, the actual risk they pose to organisms remains largely unknown. With this research, we have provided better tools to quantify this risk. First, we looked at the properties of microplastic particles. We found that microplastics are made up of a mixture of many different sizes, shapes and polymer types, which makes studying them quite challenging. We then quantified how many microplastics can be found in rivers in the Netherlands, using both measurements and models. We observed that concentrations vary in both space and time, spanning many orders of magnitude. Finally, we quantified the risk that these microplastic mixtures pose to aquatic organisms living in the water or the sediment in Dutch rivers. Our results suggest that species living in the water might be at risk, although this again varies in space and time.