Microplastics in the environment: Interactions with microbes and chemical contaminants

Microplastics (MPs) are contaminants of emerging concern that have gained considerable attention during the last few decades due to their adverse impact on living organisms and the environment. Recent studies have shown their ubiquitous presence in the environment including the atmosphere, soil, and water. Though several reviews have focused on the occurrence of microplastics in different habitats, little attention has been paid to their interaction with biological and chemical pollutants in the environment. This review therefore presents the state of knowledge on the interaction of MPs with chemicals and microbes in different environments. The distribution of MPs, the association of toxic chemicals with MPs, microbial association with MPs and the microbial-induced fate of MPs in the environment are discussed. The biodegradation and bioaccumulation of MPs by and in microbes and its potential impact on the food chain are also reviewed. The mechanisms driving these interactions and how these, in turn, affect living organisms however are not yet fully understood and require further attention. [Display omitted] •Microplastics serve as carriers of microbial pathogens and toxic chemicals in the environment.•Partitioning coefficients from conventional and indirect models can explain chemical sorption on MPs.•Microplastics could provide a conducive environment for antibiotic resistant gene exchange.•Different pathways for microplastics accumulation in microbes are postulated.•Microplastics accumulation in microbes could pose an adverse effect on their growth and metabolism.