Center for Environment, Health, and Welfare Research, Korea Institute of Science and Technology (KIST), Seoul, Korea.
Energy Environment Policy and Technology, Graduate School of Energy and Environment, Korea University, Seoul, Korea.
Indoor Air. 2021 Jul;31(4):1134-1143. doi: 10.1111/ina.12816. Epub 2021 Mar 8.
After the WHO designated COVID-19 a global pandemic, face masks have become a precious commodity worldwide. However, uncertainty remains around several details regarding face masks, including the potential for transmission of bioaerosols depending on the type of mask and secondary spread by face masks. Thus, understanding the interplay between face mask structure and harmful bioaerosols is essential for protecting public health. Here, we evaluated the microbial survival rate at each layer of commercial of filtering facepiece respirators (FFRs) and surgical masks (SMs) using bacterial bioaerosols. The penetration efficiency of bacterial particles for FFRs was lower than that for SMs; however, the microbial survival rate for all tested masks was >13%, regardless of filtration performance. Most bacterial particles survived in the filter layer (44%-77%) (e.g., the core filtering layer); the outer layer also exhibited significant survival rates (18%-29%). Most notably, survival rates were determined for the inner layers (<1% for FFRs, 3%-16% for SMs), which are in contact with the respiratory tract. Our comparisons of the permeability and survival rate of bioaerosols in each layer will contribute to bioaerosol-face mask research, while also providing information to facilitate the establishment of a mask-reuse protocol.
世界卫生组织宣布 COVID-19 为全球大流行后，口罩在全球范围内成为了宝贵的商品。然而，关于口罩仍存在一些不确定因素，包括根据口罩类型生物气溶胶传播的可能性以及口罩的二次传播。因此，了解口罩结构与有害生物气溶胶之间的相互作用对于保护公众健康至关重要。在这里，我们使用细菌生物气溶胶评估了商业过滤式面罩呼吸器 (FFR) 和外科口罩 (SM) 每个层的微生物存活率。细菌颗粒对 FFR 的穿透效率低于 SM；然而，所有测试口罩的微生物存活率均>13%，无论过滤性能如何。大多数细菌颗粒存活在过滤层中（44%-77%）（例如，核心过滤层）；外层也表现出显著的存活率（18%-29%）。值得注意的是，内层的存活率也有所确定（FFR 为<1%，SM 为 3%-16%），因为内层与呼吸道接触。我们对每个层中生物气溶胶的渗透性和存活率的比较将有助于生物气溶胶-口罩研究，同时也为制定口罩重复使用协议提供信息。
