Reactive oxygen species-induced microplastics aging: Implications for environmental fate and ecological impact

Microplastics (MPs) undergo aging when exposed to reactive oxygen species (ROS), modifying their physical properties, bioavailability, and toxicity, ultimately influencing their environmental fate and transport. Understanding ROS-induced MPs aging is crucial for predicting long-term environmental consequences and developing effective mitigation strategies. This review presents a thorough overview of the current knowledge regarding the generation of ROS from various environmental sources and its impact on MPs. It addresses the mechanisms, behaviors, and assessment of the environmental impact of ROS-induced MPs aging, as well as the quantification and identification of aging processes. Additionally, it explores potential mitigation strategies and discusses policy implications. Despite significant progress, gaps in our knowledge remain, including accurate quantifying aging processes, identifying specific ROS involved, and assessing their influence on MPs fate and toxicity. Future research should prioritize addressing these knowledge gaps to enhance our understandings of MPs aging and its implications for environmental health and food safety.