Harmful effects of microplastics on respiratory system of aquatic animals: A systematic review and meta-analysis

The presence of microplastics in the aquatic environment has attracted widespread attention. A large number of studies have assessed the effects of microplastics on the respiratory system of aquatic animals, but the results are not directly comparable across studies due to inconsistent evaluation criteria. Therefore, we adopted an integrated research approach that can integrate and parse complex data to improve reliability, conducted a systematic review and meta-analysis of 35 published studies, and elucidated the mechanisms of microplastic damage to cells. The results showed that PE had the greatest impact on aquatic animals, and fish were the most sensitive to the effects caused by microplastics, with oxidative stress induced by exposure concentrations exceeding 1000 µg/L or exposure times exceeding 28 days, leading to depletion of antioxidant defenses, cellular damage, inflammatory responses, and behavioral abnormalities. As this review is based on existing studies, there may be limitations in terms of literature quality, data availability and timeliness. In conclusion, we suggest to combat microplastic pollution by limiting plastic use, promoting plastic substitution and recycling, and enhancing microplastic capture degradation technologies.