Tire wear particles in aquatic ecosystems: Current knowledge and future perspectives

Tire wear particles (TWPs) are underappreciated microplastics. However, their presence in aquatic ecosystems has not received equal attention as that in the atmosphere and soil, which hinders TWP pollution recognition and mitigation efforts. Acknowledging their unique hazards, this review summarizes the current knowledge on TWP occurrence, behaviors, biological effects, and remediation technologies in aquatic ecosystems. TWPs have been found in waters worldwide; but their transport and distribution can not be fully assessed due to the lack of standardized analytical methods. In vivo bioassays and field investigations have indicated TWPs’ toxicity on aquatic organisms at various trophic levels. Based on environmental behaviors of TWPs, promising remediation technologies with an emphasis on source reduction, interception, and end-of-pipe treatment are proposed. Finally, this review highlights the limitations of current knowledge and provides a timely guidance for future research on TWP analysis, toxicity assessment and pollution mitigation.