Inhibitory effects of facemasks and eyeglasses on invasion of pollen particles in the nose and eye: a clinical study.

The incidence of Japanese cedar pollinosis is estimated to be about 13% of the Japanese population. In Japan it is generic to wear a facemask and eyeglasses to prevent pollen inhalation. We examined the usefulness of a facemask and eyeglasses in cooperation with volunteers. The number of pollen particles in the nasal cavity and on the conjunctiva was unchanged by wearing a facemask and eyeglasses. However, the pollen invasion rate was lower in subjects with a facemask and eyeglasses than in subjects without a facemask and eyeglasses. The decrease in pollen invasion rate in the nasal cavity due to wearing a facemask was statistically significant. This suggested that wearing a facemask has a protective effect on pollen invasion to the nose. The pollen invasion rate in the nasal cavity and on the conjunctiva was increased with increases in the wind speed. It may be difficult to avoid pollen even when wearing a facemask and eyeglasses when the wind speed is high. Further study is required to clarify the relationship between the amount of allergens and clinical symptoms.