Ambient PM2.5 and its chemical constituents on lifetime-ever pneumonia in Chinese children: A multi-center study

The long-term effects of ambient PM2.5 and chemical constituents on childhood pneumonia were still unknown. A cross-sectional study was conducted in 30,315 children the China Children, Homes, Health (CCHH) project, involving 205 preschools six cities China, to investigate lifetime-ever diagnosed pneumonia. Information demographics collected by validated questionnaires. lifetime annual average PM2.5, ozone five main constituents, including SO42?, NO3?, NH4+, organic matter (OM) black carbon (BC), estimated according preschool addresses a combination satellite remote sensing, transport modeling ground-based monitors. prevalence 34.5% across differed significantly among (p = 0.004). two-level logistic regression models showed that adjusted odds ratio for (per 10 µg/m3) its 1 µg/m3)-SO42?, OM 1.12 (95% CI:1.07–1.18), 1.02 (1.00–1.04), 1.06 (1.04–1.09), 1.05 (1.03–1.07) 1.09 (1.06–1.12), respectively. Children urban area, aged < 5 years breastfeeding time 6 months enhanced risks Our provided robust results levels increased risk pneumonia, especially NO3? OM.