Microplastic contamination in freshwater systems: Methodological challenges, occurrence and sources

Microplastics have received significant attention by the scientific community during the past decade. Knowledge on this recently considered contamination has been constantly growing, although the studies are mainly oriented toward marine environments. The focus on plastic pollution in freshwater environments has been limited even with an increasing number of studies. The fate and the transfer routes of plastics in continental are not yet determined. In addition, these studies use various and constantly evolving methodologies, leading to a lack of homogeneous and standardized methods. This hinders comparability between studies and limits potential interpretations and conclusions on plastic repartition and distribution in the continental environment. In this chapter, the studies describing the plastic contamination in freshwater are reviewed. The different methodologies for microplastic sampling, sample preparation and analysis are discussed. The occurrences of these particles in limnetic systems are also presented along with an overview on their different potential sources and input pathways into freshwater.