A review of microplastic contamination in the cryosphere.

Microplastics, recognized as an emerging and pervasive environmental contaminant, have been detected in remote cryospheric regions such as Antarctica, Arctic, Andes, Alps, and High Asia. This review synthesizes current knowledge on microplastic occurrence, sources, and transport pathways across cryospheric environments. Microplastics are transported primarily by atmospheric and hydrological processes and accumulate in snow and ice, where they act as temporary sinks. In Polar regions, sea ice plays a vital role in the storage and periodic release of microplastics, whereas high-altitude mountain systems receive significant inputs from mid-latitude emissions. The review also highlights the potential impacts of microplastics on cryospheric systems, including their role in the reduction of albedo, the acceleration of snow and ice melt, and their effects on biodiversity through ecological and trophic disturbances. Key methodological challenges in sampling, extraction, and identification point to the urgent need for standardized protocols. Overall, this review underscores the scientific significance of studying microplastic pollution in the cryosphere and offers directions for future research to improve monitoring, modeling, and impact assessment.