24th Pacific Science Congress (PSC-24)

Microplastics (MPs) and nanoplastics (NPs), as emerging global pollutants, are undergoing complex interactions with bacteria, which are becoming a key process affecting the health of aquatic ecosystems. This study aims to systematically explore the interactions between MPs/NPs and bacteria, as well as their combined effects on aquatic organisms. The research confirms the crucial role of microplastics as vectors for the transmission of pathogenic bacteria. The surface of MPs can selectively enrich unique microbial communities characterized by pathogenic bacteria, which can efficiently colonize and form biofilms within 24-48 hours. This vector effect significantly increases the pathogen load in the host and synergistically enhances the horizontal transfer of antibiotic resistance genes, posing a direct threat to the safety of aquatic products. Furthermore, this study reveals the profound impact of bacteria on the environmental behavior of NPs. Two multi-functional bacterial strains, Bacillus subtilis and Pseudomonas stutzeri, were obtained through screening. These strains can efficiently capture and ingest NPs through the secretion of extracellular polymeric substances and extracellular vesicle-like materials, respectively, while maintaining excellent nitrogen removal capabilities in water bodies. This achieves the synergistic consumption of NPs and water quality restoration, providing a new potential strategy for reducing the health risks of NPs to aquatic organisms. In summary, this study systematically elucidates the key mechanisms by which micro/nanoplastics interact with bacteria to affect the health of aquatic organisms. It breaks through the traditional single-faceted understanding of the ecological risks of plastic particles and provides important scientific evidence for the development of pollution control technologies based on interface regulation and the assurance of aquatic product safety.

microplastics, bacteria, aquatic organisms