Evaluation and risk communication of the effects of alcohol exposure on disposable procedure masks and portable air purifiers in hospital environments.

Electret technology was widely used to prevent the airborne transmission of bioaerosols during the COVID-19 pandemic and improve the filtration efficiency of masks and high-efficiency particulate air (HEPA) filters. As alcohol disinfectants are widely used in medical and welfare institutions, concerns about alcohol exposure inactivating electret exist. However, comprehensive alcohol exposure tests have not been conducted on masks and HEPA filters distributed in Japan. Twenty-five types of masks and five types of HEPA filters were subjected to a discharging process according to ISO 16890 to quantitatively elucidate the resistance to alcohol exposure. Measurements of changes in filtration efficiency and pressure drop before and after discharge show that 17 masks (68%) and four HEPA filters (80%) exhibited a significant decrease in filtration efficiency, confirming their vulnerability to alcohol. In addition, a survey (n = 500 Japanese adults, including 30 healthcare professionals) revealed that ∼90% of the general public were unaware that alcohol exposure could degrade masks and air purifiers. Furthermore, 36% of the surveyed healthcare professionals had sprayed alcohol directly onto their masks. The effectiveness of user warnings through product labels and instructions was investigated from the perspective of ensuring the safety of patients and healthcare professionals. Results revealed that the best approach was to describe the extent and duration of the adverse effects caused by disregarding precautions. Increase in awareness of healthcare professionals and general public by authorities and manufacturers through guidelines and warning labels would reduce the risk of inhaling bioaerosols caused by unintentional electret inactivation.