Combined exposure effects: Multilevel impact analysis of cycloxaprid and microplastics on Penaeus vannamei

In real environments, multiple pollutants often coexist, so studying the impact of a single pollutant does not fully reflect the actual situation. Cycloxaprid, a new neonicotinoid pesticide, poses significant ecological risks due to its unique mechanism and widespread distribution in aquatic environments. Additionally, the ecological effects of microplastics, another common environmental pollutant, cannot be overlooked. This study explored the ecotoxicological effects of cycloxaprid and microplastics, both alone and in combination, on Penaeus vannamei over 28 days. The results revealed significant physiological impacts, with notable changes in the shrimp immune system and hepatopancreatic energy and lipid metabolism. Key findings include alterations in hemocyanin, nitric oxide, and phenol oxidase levels, along with disturbances in Na⁺/K⁺-, Ca²⁺-, and Mg²⁺-ATPase activities. Additionally, neural signaling disruptions were evidenced by fluctuations in acetylcholine, dopamine, and acetylcholinesterase levels. Transcriptomic analysis revealed the profound influence of these pollutants on gene expression and metabolic processes in the hepatopancreas and nervous system. This comprehensive assessment underlines the potential growth impacts on shrimp and underscores the ecological risks of cycloxaprid and microplastics, offering insights for future risk assessments and biomarker identification.