Polystyrene microplastics increase Pb bioaccumulation and health damage in the Chinese mitten crab Eriocheir sinensis

Microplastics may be potential vectors for environmental contaminants such as heavy metals in the aquatic ecosystem due to their highly hydrophobic surfaces and fugacity property. To investigate the combined effects of microplastics with Pb, we exposed juvenile Chinese mitten crabs Eriocheir sinensis to different Pb concentrations (0, 5 and 50 μg/L) combined with microplastics (0 and 400 μg/L) for 21 days to determine the Pb bioaccumulation, oxidative stress, lipid anabolism, and histopathology of hepatopancreas. In general, the results showed that compared to single Pb exposure, the combination of MPs and Pb significantly increased the bioaccumulation of Pb, activities/content of antioxidant biomarkers and lipid metabolism enzymes, and liver injury parameters in crabs, indicating MPs are potential vector of heavy metals and co-exposure exerts more severe effects on crabs. This study provides the insights into the oxidative defense and preliminary lipid anabolism of economic crustaceans in response to combined stress of Pb and MPs.