Air Pollution Constituents that Influence the Frequency and Severity of Children's Asthma Exacerbations

JONATHAN THORNBURG, RTI International

     Abstract Number: 254
     Working Group: Aerosol Exposure

Abstract
Asthma exacerbations are responsible for 1.8 million emergency room visits and 0.4 million hospitalizations in the USA each year, constituting a major public health problem and economic burden. We measured personal exposure to air pollution in a cohort of exacerbation prone asthmatic children (n = 120, pre-COVID) in Denver, Colorado. Our goal is to identify the air pollution constituents that influence exacerbation frequency and severity. The personal and indoor exposure measures included PM10 mass concentration and black carbon (BC), tobacco smoke (ETS), and brown carbon (BrC) measured by the MicroPEM; NO2 and O3 concentrations from Ogawa passive samplers; and allergens from questionnaires. Exhaled nitric oxide (FeNO), spirometry, and CASI score assessed lung inflammation. Personal-indoor pollutant correlations followed established trends: personal PM10 greater than indoor and weakly correlated whereas personal-indoor NO2 levels are strongly correlated. Mean PM10 and ETS exposures did not vary by season. BC was higher in the winter and BrC was lower in spring compared to other seasons. The hourly average PM10 concentrations demonstrated seasonal variations, especially in the magnitude of peak exposures. Peak PM10 exposures always occurred in the afternoon or evening with fall > summer = winter > spring. From the surveys, the presence of a dog in the home was associated with greater allergic inflammation and asthma severity. Preliminary analyses suggest personal PM10 and NO2 concentrations, but not indoor, are associated with higher FeNO. Final air pollution exposure and asthma severity associations will be presented.