Study published in Journal of Hazardous material, 2021,  looked into the risks associated with mask-wearing and the inhalation of microplastics. Some of the study findings  concluded wearing masks poses microplastic inhalation risk, reusing masks increases the risk, and surgical, cotton, fashion, and activated carbon masks wearing pose higher fibre-like microplastic inhalation risk. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7773316/