Fate, transport and degradation pathway of microplastics in aquatic environment — A critical review

Abstract

Microplastics, an emerging contaminant, is ubiquitous in almost every compartment of the environment. They are of great environmental concern not only due to their pervasive, persistent, and toxic nature but also due to their ability to act as carriers of toxic metals, microbes, pesticides, etc. Comprehensive knowledge of the transport and degradation pathways of microplastics through water bodies is a prerequisite for identifying critical issues and their effective management. In this review, the basic characteristics and various methods of analysis of microplastics in the aquatic environment is summarized. A detailed discussion of the various physical, chemical and biological mechanisms causing degradation of microplastics is presented. The influencing factors affecting the fate, transport and degradation are summarized. Emphasis has been given to include the influential factors that occur in estuarine systems on the degradation of microplastics. The review is expected to give insight into the current understanding of the fate of microplastics in the aquatic environment and directions for future research in the remediation of microplastics in the aquatic realm.