“…These microplastics threaten terrestrial and marine ecosystems, global food security, and the tourism industry and exacerbate climate change and the spread of pathogens [ 2 ]. Although the weathering and the degradation under different conditions of the most important classes of industrial polymers (including PP) were extensively studied [ 6 , 7 , 8 , 9 , 10 ], their aging behavior in the form of nonwoven fabrics, such as those used for the manufacture of disposable face masks, has been investigated mostly in general terms, essentially focusing on field observations and within recycling proposals [ 2 , 11 , 12 , 13 , 14 , 15 ]. Some studies highlight the risk of microplastic release from both surgical masks and FFP2 filtering facepiece respirators due to fragmentation processes, e.g., [ 2 , 12 , 16 , 17 ], but without focusing on the microplastic formation mechanism, especially after weathering and other aging processes.…”