This comment reframes microplastics as a transboundary atmospheric pollutant, emphasizing long-range transport, inhalation exposure, aging-driven changes in toxicity and reactivity, and potential radiative and cloud effects. We identify major observational and conceptual gaps and argue that atmospheric monitoring, transport modelling, and product standards must be integrated into plastics governance to avoid unintended increases in airborne microplastic burdens and associated health and climate risks.
Li et al. (Sat,) studied this question.