Association of Ambient PM 2.5 Components with Lung Function in Adults Aged 40-89 Years: A Cross-sectional Study in China.

This study evaluated the impact of Particulate Matter 2.5 (PM 2.5) and its components on lung function. In total, 2,045 participants aged 40-89 years were recruited for this multi-center cross-sectional study. Lung function measurements were performed. Real-time PM 2.5 and its component data were obtained from atmospheric monitoring sites. Linear mixed-effects (LME) models were used to assess the relationships between PM 2.5, its components, and lung function. Weighted quantile sum regression, quantile g-computation, and Bayesian kernel machine regression were applied to assess the joint effects of PM 2.5 components on lung function. The mean PM 2.5 concentration during the study period was 71.92 μg/m 3. Among PM 2.5 components, nitrate had the highest mean concentration (16.82 μg/m 3), followed by organic carbon and sulfate. In the LME models, PM 2.5 exposure at a 1-day lag, scaled to its interquartile range, was significantly related to decreased lung function. Specifically, forced vital capacity (FVC), forced expiratory volume in 1 s (FEV 1), one-second rate (FEV 1/FVC), peak expiratory flow (PEF), and forced expiratory flow at 25% FVC (FEF 25%) decreased by 3.75%, 6.56%, 2.89%, 10.48%, and 8.71%, respectively. An age-stratified analysis showed stronger negative associations among participants aged ≥ 60 years compared with middle-aged adults. In mixed-exposure models, the PM 2.5 mixture was significantly linked to a decline in lung function. Zinc (Zn) and magnesium ion (Mg 2+) were significantly linked to reduced FVC and ammonium ion (NH 4 +) was identified as a key contributor to reduced FEV 1, PEF, and FEF 75%. Lung function declined with increasing PM 2.5 and its components. Zn, Mg 2+, and NH 4 + were identified as key components.