Microplastic-Antibiotic Complex Pollutants on Intestinal Microbial Community Structure of Zebrafish

This study investigated the adsorption of chloramphenicol by microplastics in water and examined the effects of the combined pollutant on zebrafish gut microbiota using high-throughput 16S rRNA sequencing. The results demonstrated that the equilibrium adsorption capacity of chloramphenicol by microplastics was 2.27 mg/g, consistent with a quasi-first-order kinetic model, while the saturated adsorption capacity was 14.60 mg/g, aligning with the Langmuir adsorption model. Gut microbiota analysis revealed that in the experimental group exposed to the microplastic-antibiotic composite pollutant, the abundance of Bacteroidota and Firmicutes increased progressively, whereas the abundance of Proteobacteria and Fusobacteriota showed minimal changes. Additionally, microbial beta-diversity was significantly reduced. This study confirms that microplastics can act as carriers of chloramphenicol, enter aquatic organisms, and alter the structure of the intestinal microbial community.