Irritation of the human eye mucous membrane caused by airborne pollutants

Abstract.

Objectives: The purpose of this study was to investigate the different irritative effects of carbon dioxide and n-butanol exposure on the ocular mucous membrane. Material and methods: Provocation by the gases was at the same sensory level, which was 50% of maximum on a linear scale. The experiment was performed on nine healthy subjects with the aim of identifying the relationship between eye irritation and the human physiological response to this irritation. A goggle exposure system, invented at the Department of Occupational and Environmental Medicine, Aarhus University, was used for the experiment. The exposures lasted for 30 min each. Results: There were no changes in tear film stability and conjunctival corrosion (lissamine staining) after carbon dioxide and n-butanol exposures leading to 50% sensory eye irritation. However, the study showed a delayed inflammatory response after carbon dioxide exposure when compared with clean air. The significant change was seen for tear fluid neutrophilic granulocytes 22 h after carbon dioxide (CO₂) exposure only. Conclusions: It is concluded that the type of exposure made no difference to the elicited physiological responses and that tear film stability and epithelium damage were not affected by sensory irritation itself.