Silver-based biocides and titanium dioxide particles in face masks for general use. Final report of the TiO2Mask and AgMask COVID-19 projects., Montalvo, Daniela, Wouters Charlotte, Siciliani Lisa, Vleminckx Christiane, Van Miert Erik, Waegeneers Nadia, Van Loco Joris, Verleysen Eveline, Cheyns Karlien, and Mast Jan , 02/2023, Brussels, Belgium, p.48, (2023)