Spirometric assessment of pulmonary function in road-side vendors: A pilot study

Although much is known about the chronic effects of air pollution on pulmonary function, short-term changes in response to pollution levels over days, weeks and months have been less well documented. Such investigation requires field studies using portable equipment. Therefore, we studied forced vital capacity (FVC), forced expiratory volume in 1 second, and peak expiratory flow rate using a conventional hand-held spirometer, in a sample of Hong Kong roadside vendors (n = 21; age, 48.7 ± 13.4 yr) across 2 days (n = 14), 4 weeks (n = 10), and 3 months (n = 7). In addition, exhaled carbon monoxide was measured, and percent carboxyhemoglobin derived. There was no difference in pulmonary function between a weekday and the weekend. Only FVC decreased over 4 weeks and 3 months compared with initial testing, but this was not associated with pollution level. Our results support that the technology of hand-held spirometry needs to be advanced to detect potential short-term changes in the real world context, in pulmonary function including small airway reactivity and airway closure. Future generations of this technology need to provide the capacity for more detailed spirometry suitable for field studies.