Abstract
BACKGROUND: Air pollution-induced systemic inflammation and oxidative stress are hypothesized to be the major biological mechanisms underlying pathological outcomes. We examined the association between short-term exposure to ambient air pollutants and biomarkers of inflammation and oxidative stress in 2199 general middle-aged Korean population residing in metropolitan areas. METHODS: Serum levels of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, and tumor necrosis factor [TNF]-α) and urinary levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured. Daily concentrations of a series of air pollutants (particulate matter [PM](10), PM(2.5), SO(2), NO(2), CO, and O(3)) were predicted using the Community Multiscale Air Quality modeling system, and participant-level pollutant exposure was determined using geocoded residential addresses. Short-term exposure was defined as the 1- to 7-day moving averages. RESULTS: The multivariable-adjusted linear models controlling for the sociodemographic, lifestyle, temporal, and meteorological factors identified positive associations of PM with IL-1β, IL-8, IL-10, TNF-α, and 8-OHdG levels; SO(2) with IL-10 levels, CO with IL-1β, IL-10, and TNF-α levels; and O(3) with IL-1β, IL-8, and 8-OHdG levels. O(3) levels were inversely associated with IL-10 levels. For each pollutant, the strongest associations were observed for the 7-day average PM and CO with IL-1β (per 10-µg/m(3) increase in PM(10): 2.7%, 95% confidence interval [CI] = 0.6-4.8; per 10-µg/m(3) increase in PM(2.5): 6.4%, 95% CI = 2.4-10.5; per 0.1-ppm increase in CO: 3.3%, 95% CI = 0.3-6.5); the 2-day average SO(2) with IL-10 levels (per 1-ppb increase in SO(2): 1.1%, 95% CI = 0.1-2.1); and the 7-day average O(3) with IL-8 levels (per 1-ppb increase in O(3): 1.3%, 95% CI = 0.7-1.9). CONCLUSIONS: Short-term exposure to ambient air pollutants may induce oxidative damage and pro-inflammatory roles, together with counter-regulatory anti-inflammatory response.