From laboratory to the field: the role of microplastics as vectors of per- and polyfluoroalkyl substances (PFAS) in the environment

Per- and polyfluoroalkyl substances (PFAS) and microplastics (MPs) are new and widespread chemicals and pollutants with growing concerns due to their persistence, mobility, and threats, as well as their potential synergies in environmental and human health effects. This review gathers existing evidence on the importance of MPs as vectors of PFAS, specifically on adsorption processes, controlling variables, and inconsistencies between laboratory and field results. Laboratory investigations generally report relatively high sorption capacities, particularly for long-chain PFAS and polymers with nonpolar functional groups. Conversely, field-based investigations often report smaller and more variable adsorption capacities to biofilm formation, competition with natural organic matter, and environmental heterogeneity, despite showing similar relative trends. A geographic analysis of the literature indicates that most studies have been conducted in Asia, North America, and Europe, while other regions remain underrepresented. Overall, the results indicate that MPs can act as active carriers of PFAS rather than permanent sinks, thereby contributing to their transport, persistence, and biological exposure at different levels of the environment. This review underscores the purpose of integrated laboratory-field measures: expanded research on the emergent PFAS and enhanced analysis techniques are necessary to more accurately gauge environmental risks and inform pollution management and control metrics.