Migration and transformation of airborne microplastics

Microplastics (MPs) are ubiquitous emerging pollutants, which have been widely found in the atmospheric environment. However, the current researches on airborne MPs are still limited. In this chapter, migration and transformation of airborne MPs were summarized and discussed. Because of their unique properties, airborne MPs could stay in air for a long time, and then migrate to short-distance or long-distance locations through mechanical (e.g. atmospheric turbulence, wind and dry-wet deposition), physical-chemical and biological migration. Among them, mechanical migration plays a predominant role. During migration of airborne MPs, transformation is usually accompanied. The transformation of MPs is mainly through physical and chemical degradation (including photoreactive, hydrolytic and thermo-oxidative degradation, etc.), and biodegradation. Based on the existing research, we suggest that extensive and in-depth research should be carried out to further understand the magnitude of harm that they may cause to the human health and ecosystem.