Abstract
This study aims to assess the environmental impact of discarded face masks, that are a source of emerging concern as indicated by most recent literature, although still little investigated. Herein we evaluated micro- and nanoplastic particles that can be released from face mask once subject to environmental conditions. Exposure to simulated-low shear forces demonstrated to be effective in breaking and fragmenting face mask tissue into smaller debris. Even at low shear energy densities, a single mask could release in water thousands of microplastic fibers and up to 10^11 submicrometric particles. The latter were quantified using flow cytometry that was proven to be a promising technique for nanoplastic counting, thus improving our understanding on distribution and fate of NPs still representing a great analytical challenge in plastic pollution research.



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