Microplastics are a hotspot for antibiotic resistance genes: Progress and perspective.

Antibiotic resistance genes (ARGs) and microplastics in the environment are of great public concern due to their potential risk to human health. Microplastics can form distinct bacterial communities and absorb pollutants from the surrounding environment, which provide potential hosts and exert possible selection pressure of ARGs. We provide a practical evaluation of the scientific literature regarding this issue. The occurrence and transport of ARGs on microplastics in wastewater treatment plants, aquatic, terrestrial, and air environments were summarized. Selective enrichment of ARGs and antibiotic resistance bacteria on microplastics have been confirmed in different environments. Aggregates may be crucial to understand the behavior and transport of ARGs on microplastics, especially in the aquatic and terrestrial environment. Microplastics could be a carrier of ARGs between the environment and animals. Accumulation of pollutants and dense bacterial communities on microplastics provide favorable conditions for higher transfer rate and evolution of ARGs. More studies are still needed to understand the enrichment, transport, and transfer of ARGs on microplastics and provide a fundamental basis for evaluating their exposure health risk to humans.