Evaluation and risk communication of effects of alcohol exposure on disposable procedure masks and portable air purifiers

As electret technology can drastically improve the filtration efficiency of disposable procedure masks and portable air purifiers, it is widely used to prevent the airborne transmission of SARS-CoV-2. Furthermore, alcohol disinfectants are now widely used in offices, hospitals, and homes to prevent contact infection; hence, there is a concern that alcohol exposure may inactivate electret. In this study, 5 types of high-efficiency particulate air filter (HEPA) air purifiers—of which, one was made of fiberglass HEPA filter—14 types of cubical masks, and 11 types of pleated masks available to Japanese citizens were subjected to discharge according to the alcohol exposure protocol based on ISO (International Organization for Standardization) 16890, and changes in filtration efficiency and pressure drop were measured before and after the discharge. The results revealed that 17 (68%) of the 25 masks exhibited a significant decrease in filtration efficiency; this decrease due to discharge depended on the filter material. However, masks of polypropylene, polyethylene, and poly-vinylidene-difluoride composite fiber materials exhibited no significant decrease in filtration efficiency. In addition, 4 (80%) of the 5 HEPA filters showed a 40–64% decrease in filtration efficiency, while no decrease in filtration efficiency was observed for the fiberglass HEPA filter. Our survey (n = 500 Japanese adults, including 30 healthcare professionals) revealed that approximately 90% of the general public was unaware that the performance of masks and air purifiers could be degraded by direct spraying of alcohol—for disinfection purposes—or vapor exposure. Furthermore, 36% of the surveyed healthcare professionals indicated that they had sprayed alcohol directly on their masks. Therefore, based on the results of this experiment, we examined effective consumer warnings that could be utilized on the product labels and in the instructions. The results showed that it would be more effective to detail the extent and duration of the adverse effects of disregarding the precautions.驻极体（electret）技术可显著提升一次性医用口罩与便携式空气净化器的过滤效率，因此被广泛应用于阻断SARS-CoV-2的空气传播。此外，酒精消毒剂目前已在办公场所、医院及家庭中广泛用于预防接触感染，故而人们担忧酒精暴露可能会使驻极体失活。本研究针对日本民众可购得的5款高效微粒空气过滤器（high-efficiency particulate air filter, HEPA）空气净化器（其中一款采用玻璃纤维（fiberglass）HEPA滤材）、14款立体口罩及11款褶皱式口罩，按照基于国际标准化组织（International Organization for Standardization, ISO）16890制定的酒精暴露方案进行放电处理，并检测处理前后的过滤效率与压降变化。结果显示，25款口罩中有17款（占比68%）的过滤效率出现显著下降，该降幅与滤材类型相关。不过，采用聚丙烯（polypropylene）、聚乙烯（polyethylene）及聚偏氟乙烯（poly-vinylidene-difluoride）复合纤维材质的口罩，其过滤效率未出现显著下降。此外，5款HEPA空气净化器中有4款（占比80%）的过滤效率下降了40%至64%，而采用玻璃纤维（fiberglass）滤材的HEPA净化器未出现过滤效率下降。本次调研共招募500名日本成年人（其中30名为医护人员），结果显示约90%的普通民众并不知晓，用于消毒的酒精直接喷洒或酒精蒸汽暴露，可能会降低口罩与空气净化器的性能。此外，受访医护人员中有36%表示，他们曾直接在口罩上喷洒酒精。因此，本研究基于实验结果，探讨了可应用于产品标签与使用说明书的有效消费者警示方案。结果表明，详细说明忽视防护注意事项所带来的不良影响程度与持续时间，会使警示更具实效。