Indoor air pollution and respiratory health in a metropolitan city of Pakistan

Abstract

Objective We assessed the association of formaldehyde, Carbon Monoxide (CO) and Particulate Matter (PM2.5) with respiratory symptoms, asthma and post-bronchodilator reversibility. Methods We included 1629 adults in a community-based cross-sectional study in Karachi, in 2015. Data was collected using American Thoracic Society respiratory questionnaire, and spirometry (available for 930 participants). YesAir 8-channel monitor was used for measuring concentrations of formaldehyde and CO while PM2.5 was measured using UCB-PATS. Results Higher levels of formaldehyde and CO were associated with cough, phlegm and wheeze whereas those of PM2.5 were associated with shortness of breath and presence of any of the respiratory symptoms (combined), as well as a ‘lower’ risk of cough, phlegm and bronchitis. Conclusion Poorer household air quality was associated with poorer respiratory health in this population; however further studies are required with robust exposure assessment.