Identification and Assessment of Potential Microplastic Emissions within the Lake Tollense Catchment Area, Mecklenburg-Western Pomerania, Germany

The present study was carried out within the MICROLIM project funded by the German Research Foundation DFG, which aims at an overall assessment of microplastic concentrations in different environmental compartments of the Lake Tollense catchment. Here, we address potential input sources of microplastic and their occurrence in the catchment and provide first estimates of emission volumes based on population density, agricultural activities and traffic. The land cover of the Lake Tollense catchment, located in Mecklenburg-Western Pomerania, Germany, is dominated by agriculture and comprises the city of Neubrandenburg in the Northern part of the lake and additional minor settlements in the rural areas. The catchment area is divided into six sub-catchments according to the lake’s tributaries. The methodological approach comprised (1) a literature review of potential sources of microplastic, their potential composition, application approaches and possible effects on the environment, (2) the determination of land use types within the lake Tollense catchment via a descriptive land-use analysis and examination of the identified land-use types for the occurrence of microplastic-emitting applications according to the initial literature review and (3) a quantitative estimation of the emission volumes of the population (including tourists), transport and agricultural activities in the catchment area, applying specific emission rates. Potential microplastic emissions could be identified from urban agglomerations and the agricultural and transport sectors. The first quantifications of the emission potential of particulate matter in the size of 10 µm (PM10) from the transport sector resulted in an average of 14.5 tons per year on state and federal roads. The total annual emission volume of the population in the study area is estimated at an average of 138.6 tons per year. The calculated volumes of particulate emissions from roads and traffic indicate that transport is the most important emission source in the Lake Tollense catchment area.