Background: Previous studies relate sulfur dioxide (SO2) exposure with asthma exacerbations. We utilized the University of Pittsburgh Asthma Institute registry (AIR) to study associations of asthma exacerbations between two geographically distinct adult asthma populations.
Objective: The objective was to examine if asthma symptoms worsened following a significant fire event that destroyed pollution control equipment at the largest Coke Works in the United States. Methods: Two groups of asthma patients 1) those residing within 10 miles of the Coke Works Fire (CWF) “proximal group” (n=39), and 2) those beyond that range “control group” (n=44) were geocoded by residential address. Concentrations of ambient air SO2 were generated using local AIR monitor data. Factory emissions were also evaluated. Patient historical, acute exposure survey and in-person follow-up data were evaluated. Inferential statistics were used to compare groups.
Results: In the immediate post-fire period (6-8 weeks), there was increase in SO2 factory emissions of 25 times above typical emissions. Following the pollution control breach, the proximal cohort self-reported an increase in medication usage (RR: 1.76, 95% CI 1.1-2.8, p<0.01) and more exacerbations. In a small subset of the follow-up cohort of those who completed the acute survey only, asthma control metrics improved.
Conclusions: A real world exposure to a marked increase in ambient levels of SO2 from a pollution control breach associated with worsened asthma control in patients proximal to the event, which improved following repair of the controls. Improved spatial resolution of air pollutant measurements would enable better examination of exposures and subsequent health impacts.
Authors: Brandy M Byrwa-Hill, Albert A Presto, Sally Wenzel, James P Fabisiak
; Full Source: The Journal of allergy and clinical immunology 2021 Apr 21;S0091-6749(21)00649-7. doi: 10.1016/j.jaci.2021.04.011.