Associations Between Ambient and Indoor Air Pollution Exposure and the Presence of Rhinitis Symptoms in the Past 12 Months: Income-Related Differences in a General Adult Population

Abstract

Previous studies on the associations between exposure to various indoor air pollutants, as well as coexposure to ambient and indoor air pollutants, and rhinitis are limited. Data from the Korea National Health and Nutrition Examination Survey (2020-2021) were analyzed (n = 1812). Ambient air pollutant concentrations were estimated using the Community Multiscale Air Quality model, while indoor air pollutant concentrations were measured in each household. Associations with the presence of rhinitis symptoms in the past 12 months (PRS) were examined using logistic regression models for individual ambient and indoor air pollutants, as well as for a composite exposure variable that combined ambient fine particulate matter (PM2.5) and indoor total volatile organic compound (TVOC) concentrations (low-low, low-high, high-low, and high-high). Stratified analyses by household income were conducted using the same models. A doubling of ambient PM2.5 concentrations over 1 year was associated with higher odds of PRS (odds ratio [OR] = 2.68, 95% confidence interval [CI]: 1.45, 4.78). A doubling of TVOC (OR = 1.08, 95% CI: 1.01, 1.16) and toluene (OR = 1.10, 95% CI: 1.02, 1.20) concentrations was associated with higher odds of PRS. Compared to the low-low group, other composite exposure groups had increased odds of PRS. These associations were more pronounced among individuals with lower income than among those with higher income. Ambient and indoor air pollution exposures were both individually and collectively associated with a higher risk of rhinitis symptoms among adults. Since this study used a cross-sectional design, further longitudinal studies are needed.