Ecological Impact of PVC Microplastics on Microbial Communities in Wet Waste Treatment Systems

The ecological impact of PVC microplastics on the microbial community in the wet waste treatment system mainly comes from three joint effects: particle persistence, microbial colonization of particle surfaces, and the continuous release of chemicals such as additives under high humidity, strong microbial activity and fluctuating physicochemical conditions. Compared with the relatively inert polyolefins, PVC contains chlorine-containing main chains and often contains plasticizers and stabilizers, so it is more likely to trigger physicochemical stress caused by particle surface interaction and additive release at the same time. This review focuses on the occurrence, transport, and fate of PVC in the process of pretreatment, aerobic composting and anaerobic digestion, focusing on surface aging, preferential microbial colonization, and the differences between attached communities and bulk-phase microbial communities. Studies have shown that the impact of PVC microplastics on wet waste treatment systems is not a single exposure effect, but the result of surface aging, interface colonization, additive release and co-pollutant coupling. These processes ultimately alter microbial community structure, functional organization, and overall treatment performance, particularly by disrupting key metabolic pathways involved in methane production. In general, PVC is more likely to be enriched in the solid phase and persists throughout the treatment process; its additive leaching is obviously time-dependent and strongly affected by environmental conditions. This suggests that microbial communities are more likely to experience chronic stress than transient disturbance. Future research should focus on how PVC properties and additive release interact under real operating conditions, and further clarify the mechanisms by which they affect microbial community structure, function, and treatment performance.