The plasma-plastic paradox: breaking down plastics, building up risk?

Cold plasma has recently emerged as a promising advanced oxidation approach for the treatment of microplastics, with reported effects ranging from surface oxidation and aggregation to fragmentation, mass loss and, in selected reactor configurations, near-complete mineralization. However, the current evidence base remains fragmented across water, soil, aging, co-contaminant and plastic-conversion studies, and reported performance metrics are not directly comparable. This perspective argues that cold plasma should be assessed not only as a remediation technology, but also as a process capable of transforming microplastic-associated risk. We propose a four-axis framework for future studies, covering: abatement, degradation products, mobility, and ecotoxicological effects. Applying this framework reveals that most existing studies report only partial physicochemical evidence, while energy-normalized abatement, multiphase transformation products, transport behavior and biological endpoints remain poorly integrated. We conclude that cold plasma could become relevant for targeted microplastic treatment scenarios, particularly as part of engineered treatment trains, but only if future research demonstrates net risk reduction under environmentally and operationally realistic conditions.