Research on the effect of simulated migration from disposable PLA tableware on gut microbiota

Polylactic acid (PLA) has been widely used in disposable tableware. However, when disposable PLA tableware comes into contact with food, the potential effects of their migrants on the human gut microbiota are still unclear. In this study, a PLA water cup and a PLA meal box on the market were taken as the research objects. The main materials of the products were identified by infrared spectrum analysis. The total migration of these products under different soaking conditions was tested, and the results showed that the total migration was less than 10 mg·dm−2. By simulating in vitro digestion combined with 16S microbial diversity analysis, the effects of the migrants from PLA tableware in lipid food substitute simulants (95% ethanol) on the gut microbiota and the content of short-chain fatty acids (SCFAs) were investigated. The results revealed that the migrants from PLA cup and meal box altered the diversity and composition of the gut microbiota and increased the abundance of microbiota associated with gut microflora dysbiosis and inflammation, such as the Proteobacteria and Campylobacterota phyla. In addition, the migrants of two PLA products had potential effects on multiple metabolic pathways. Among them, the migrants of meal box had the most significant effect on the structure of gut microbiota, and inhibited the production of acetic, butyric, isobutyric acid, and the degradation of propionic acid. In summary, the migrants released from disposable PLA tableware in contact with lipid food may have potential negative effects on the gut microbiota. Therefore, it is urgent to pay attention to the migration behavior of micro/nano plastics and chemical pollutants from PLA tableware, as well as the potential hazards of migrants to human gut health.