Exposure to air pollution and pulmonary function in university students

Objectives: Exposure to air pollution has been reported to be associated with increase in pulmonary disease. The aims of the present study were to examine the use of personal nitrogen dioxide (NO₂) samplers as a means of measuring exposure to air pollution and to investigate the relationship between personal exposure to air pollution and pulmonary function. Methods: We measured individual exposures to NO₂ using passive personal NO₂ samplers for 298 healthy university students. Questionnaire interview was conducted for traffic-related factors, and spirometry was performed when the samplers were returned after 1 day. Results: Personal NO₂ concentrations varied, depending on the distance between residence and a main road (P=0.029). Students who used transportation for more than 1 h were exposed to higher levels of NO₂ than those using transportation for less than 1 h (P=0.032). In terms of transportation, riding in a bus or subway caused significantly higher exposure than not using them (P=0.046). NO₂ exposure was not significantly associated with forced vital capacity (FVC) or forced expiratory volume in 1 s (FEV₁) but was associated with the ratio of FEV₁/FVC and mid-expiratory flow between 25% and 75% of the forced vital capacity (FEF_25–75) (P<0.05). Conclusions: This study indicates that concentrations of personal exposure to NO₂ are significantly influenced by traffic-related air pollution and are associated with decreased pulmonary function.