Effect of wearing a face mask on microclimate around the eyes and the tear film

Abstract

Eye discomfort is a major complaint reported in indoor spaces and has been suggested to be exacerbated by environmental conditions such as low humidity and high air velocity. Wearing face masks, which has become essential in our daily lives during the COVID-19 pandemic, can also cause eye discomfort by affecting the microclimate around the eyes. We conducted a pilot study to evaluate the effect of wearing masks on eye discomfort by measuring the physical environment around the eyes and short-term physiological and psychological responses and comparing them with and without surgical face masks. The results showed that when the participant wore a mask, exhaled air flowed out through the gap at the top edge of the mask, resulting in a higher air velocity and absolute humidity around the eyes than when the mask was not worn. No significant differences were found in subjective discomfort, tear-film stability, ocular surface temperature or blink frequency. However, the tear evaporation rate, estimated based on physical measurements, was greater when wearing a mask than when not wearing it. This study revealed that wearing face masks can negatively affect the environment around the eyes in terms of tear-film health.