Impact of nano-sized plastic on the nutritional value and gut microbiota of whiteleg shrimp Litopenaeus vannamei via dietary exposure

Contamination of the world's oceans with plastic waste has attracted increasing attention in recent years. Whereas the ecological consequences of plastic pollution have been the focus of increasing research, the health-related implications of plastic pollution have been somewhat overlooked. In this study, we exposed whiteleg shrimp (Litopenaeus vannamei), a widely consumed marine species, to nano-sized plastic (polystyrene) via a simulated marine food chain in which mussel (Mytilus edulis) was the food source, and evaluated the effects of plastic contamination on shrimp physical, biochemical, and nutritional characteristics over a 21-day exposure period. We identified the changes in certain important biochemical and nutritional indicators, including changes in the gut microbiota and contents of amino acids and fatty acids. The biochemical analysis revealed that microbial activities in the intestine and the glutathione S-transferase and superoxide dismutase activities changed in L. vannamei exposed to nano-sized plastic. In these individuals, the levels of some essential amino acids and fatty acids also decreased. Overall, our findings indicate that plastic pollution can directly interfere with nutritional changes in marine food resources, thereby indirectly causing potential health implications for human consumers.