Polystyrene nanoplastics amplify the toxic effects of PFOA on the Chinese mitten crab (Eriocheir sinensis)

Nanoplastics (NPs), the final form of degraded microplastics in the environment, can adsorb PFOA (an emerging organic pollutant in recent years) in several ways. Current research on these has focused on bony fishes and mollusks, however, the combined toxicity of PFOA and NPs remains unknown in Eriocheir sinensis. Therefore, the effects of single or combined exposure to PFOA and NPs were investigated. The results showed that NPs aggravated PFOA exposure-induced oxidative stress, serum lipid disorders, immune responses, and morphological damage. DEGs altered by NPs-PFOA exposure were predominantly enriched in GO terms for cell lumen, and organelle structure, and KEGG terms for spliceosome and endocrine disorders-related diseases. Notably, the apoptotic pathway plays a central role enriched under different exposure modes. PFOA or NPs-PFOA exposure disrupted the levels of lipids molecules-related metabolites by mediating the glycerophospholipid pathway, and the NPs mediated the ferroptosis pathway to exacerbate PFOA-induced metabolic toxicity. In addition, NPs exacerbated the inflammatory response and metabolic imbalance by mediating Fusobacterium ulcerans in the intestinal. In conclusion, this study provides a valuable reference for the characterization of NPs-PFOA combined pollution and a scientific basis for the development of environmental protection policies and pollution management strategies.