Microplastics in de Nederlandse zoete wateren: Herkomst en samenstelling van microplastics in relatie tot degradatie van plastics, en de mogelijke gevolgen van (micro)plastics voor mens en milieu

ABSTRACT \n \nFor this consultancy report the current environmental state regarding microplastics in the Dutch freshwater systems has been investigated. In this report, plastics are classified according to occurrence and distribution in the freshwater environment, transport routes, polymer material, fabrication process, and use and behavior in freshwater systems. Influencing factors for plastic degradation are primarily dependent on abiotic factors such as light and mechanical erosion. The main biotic factors influencing degradation processes are biofouling and biofilm formation. Ecotoxicological effects and implications for human health of plastic degradation comprise possible bioaccumulation in organisms and exposure through consumption of organisms contaminated with microplastics. Plastics may contain potentially harmfull additives. Plastic litter could be an emmission source of these chemicals for the freshwater environment. Plastics also show the ability to sorb substances like polycyclic aromatic hydrocarbons and heavy metals. The water salinity does not seem to have an effect on this sorption behaviour. Experiments have shown that ingestion of microplastics can lead to harmfull amounts of chemicals within organisms. If (micro)plastics are not remediated before or shortly after disposal in the freshwater environment, they will likely accumulate in freshwater systems. A complete monitoring system with surveillance and monitoring should be able to provide further insight, and also can be useful in measuring the effectiveness of policy formulation related to water management strategies.