Chapter 6 - Occurrence of MPs and NPs in freshwater environment

Abstract

Microplastics (MPs) and nanoplastics (NPs) are becoming a worldwide concern. The ubiquitous dispersion of MPs/NPs in both terrestrial and aquatic environments is growing because of increase in the production and use of plastics globally. Freshwater systems such as lakes and rivers facilitate the transport of plastic particles from urban to marine environments. The presence and potential ecotoxicological effects of MPs in freshwater systems are not clearly understood. The co-occurrence of MPs/NPs with other biological and chemical contaminants such as pathogenic microorganism or heavy metals adds higher complexity to this rapidly growing pollution. Tracking and identification of the fate of plastic debris in freshwater is critical to development of mitigation strategies. In this chapter, the occurrence and sources of MPs/NPs in freshwater ecosystems are summarized. Mass flow, global river, and spatiotemporally explicit models are discussed. These can complement the information on tracking and fate of these particles and help understand these systems better. In addition, interactions of plastic particles with the microbial communities affecting the biofilm formation and biodegradation process are reviewed. As the water cycle is site specific, interconnected, and its components have similar dynamic environment, presenting global freshwater-specific information is challenging. We tried our best to highlight the important role of freshwater system with regards to MP/NP pollution.