Microplastics in cloud cycles: Systematic review and the role of hybrid technology

ABSTRACT Atmospheric microplastics (AMPs), defined here as plastic particles ranging from 1 μm to 5 mm, can remain airborne, undergo long-range transport, and reach remote environments. This review synthesises evidence on AMP occurrence, atmospheric cycling, cloud interactions, and emerging technological approaches for their management. A PRISMA-guided systematic search of Scopus and Google Scholar identified 62 studies published between 2015 and 2025, supplemented by 25 publications addressing emerging monitoring, capture, and remediation technologies. Fibres were the dominant morphology, while particles <100 μm represented the most frequently reported size category. Polyethylene terephthalate (PET) was the most frequently reported individual polymer, although mixed polymer assemblages were more common overall. Urban activities emerged as major emission sources, while atmospheric circulation, including monsoon systems and dust events, facilitates long-range transport. Atmospheric aging may enhance interactions with cloud droplets and ice, potentially enabling AMPs to act as cloud condensation nuclei (CCN) or ice nucleating particles (INP). However, direct field evidence of their atmospheric significance remains limited. Wet deposition represents a major removal pathway, while resuspension from terrestrial and marine surfaces may sustain continued atmosphere to surface cycling. Emerging hybrid sensing platforms and functional materials offer potential for AMPs monitoring, capture, and remediation, but their performance under realistic atmospheric conditions remains largely unvalidated. Effective AMPs management therefore requires both emission reduction at source and development of atmosphere specific technologies capable of monitoring and mitigating their atmospheric persistence.