Changes in the ocular and nasal signs and symptoms of aircrews in relationto the ban on smoking an intercontinental flights

Objectives This study determined the influence of exposure to environmental tobacco smoke (ETS) in aircraft on measured and perceived cabin air qualit y (CAQ), symptoms, tear-film stability, nasal patency, and biomarkers in na sal lavage fluid. Methods Commercial aircrews underwent a standardized examination, including acoustic rhinometry, nasal lavage, and measurement of tear-film break-up t ime. Eosinophilic cationic protein, myeloperoxidase, lysozyme: and albumin were analyzed in the nasal lavage fluid. Inflight investigations [participa tion rate 98% (N=39)] were performed on board 4 flights, 2 in each directio n between Scandinavia and Japan. Scandinavian crew on 6 flights from Scandi navia to Japan participated in postflight measurements after landing [parti cipation rate 85% (N=41)]. Half the flights permitted smoking on board, and the other half, 0.5 months later, did not. Hygienic measurements showed lo w relative air humidity on board (2-10%) and a carbon dioxide concentration of <1000 ppm during 99.6% of the cruising time. Results The smoking ban caused a drastic reduction of respirable particles, from a mean of 66 (SD 56) <mu>g/m(3) to 3 (SD 0.8) mug/m(3). The perceived CAQ was improved, and there were fewer symptoms, particularly ocular sympt oms, headache and tiredness. Tear-film stability increased, and nasal paten cy was altered. Conclusions Despite a high air exchange rate and spatial separation between smokers and nonsmokers, smoking in commercial aircraft may cause significa nt air pollution, as indicated by a large increase in respirable particles. This ETS exposure is associated with an increase in ocular and general sym ptoms, decreased tear-film stability, and alterations of nasal patency.