A research team at Gacheon University Gil Medical Center has found that high levels of ozone (O3) in the atmosphere can increase dry eye syndrome.
The study is the world's first clinical study to correlate ozone directly with dry eye syndrome.
The team, led by Professor Kim Dong-hyun at the hospital, studied 33 subjects with dry eye syndrome and found that ozone concentration significantly influenced the changes in subjective symptoms and tear secretion of dry eye syndrome.
Ozone is a trace gas in the atmosphere, a major source of free oxygen radicals, and a primary photochemical smog oxidant. Ozone has several adverse effects, including respiratory illness, malignant asthma, dermatitis, and increased mortality in the body. The government measures and releases ozone levels daily and issues ozone warnings if the ozone concentration increases during the hot summer months.
The study involved 66 eyes of 33 patients, including seven males and 26 females, with an average age of 55.2 years.
The team examined the subjects' average atmospheric ozone concentration, ocular surface disease index (OSDI) score, tear secretion, and tear breakdown time, every week for two months, and used the average of the daily ozone concentrations to calculate the monthly ozone concentrations.
The ozone concentration at the initial visit was 0.019 ± 0.017ppm.
As a result, when the ozone concentration increased by 0.01 ppm, the OSDI score increased by 3.43 points, and the tear secretion decreased by 1.43 mm.
Such changes are drastic enough for the patient to feel significant discomfort. However, the team also confirmed that there was no correlation between tear breakdown time and corneal fluorescence staining scores and ozone concentration.
"In other words, as the ozone concentration in the air increases, eye discomfort increases, and tears secretion decreases," the hospital said in a news release. "Such a phenomenon was more noticeable in women than in men."
Professor Kim also said, "When a patient with dry eye syndrome is exposed to high atmospheric ozone levels for about a week, eye discomfort increases, and tear secretion decreases. The study is the world's first prospective clinical study to identify the relationship between ozone and dry eye syndrome, which is significant in that it was consistent with previous epidemiological studies."
Therefore, there needs to be more attention paid to the effects of ozone on eye health, Kim added.
The journal Cornea published the result of the study.
<© Korea Biomedical Review, All rights reserved.>