Assessment of the filtration efficiency and antibacterial activity of reusable antibacterial face masks after washing

Abstract This study evaluated the filtration efficiency, and continuity of the antibacterial activity of reusable antibacterial silver, copper, and graphene antibacterial masks before and after washing. The masks were washed at three different temperatures (40 °C, 60 °C, 90 °C) and up to 10 washing cycles. The filtration efficiencies of the three reusable antibacterial masks were between 10 and 13% before washing and increased by approximately 6% after washing. Before washing, the bacterial filtration efficiency was between 93 and 98%. The antibacterial activity was 98% for both the silver and copper masks, and 88% for the graphene mask. All these values were higher than those of non-antibacterial masks. There were no trends in performance difference with increasing washing temperature or cycles, and performance did not change significantly compared to before washing, regardless of the temperature or washing cycles. Under certain testing conditions, the bacterial filtration efficiency of the three reusable antibacterial masks was < 95%, indicating that they might not be able to block effectively bacterial particles. Therefore, in the context of public health, the use of certified masks in daily life is strongly advised to ensure effective respiratory protection for the respiratory system and to mitigate potential health risks from aerosols and bioaerosols. Graphical Abstract