The Acute Effects of Fine Particulate Matter Constituents on Blood Inflammation and Coagulation

Limited evidence is available on the effects of various fine particulate matter (PM_2.5) constituents on blood inflammation and coagulation. We examined the associations between 10 constituents and 10 circulating biomarkers in a panel of 28 urban residents with four repeated measurements in Shanghai, China. Based on the linear mixed-effect models, we fitted the single-constituent models, the constituent-PM_2.5 joint models, and the constituent-residual models to evaluate the associations between PM_2.5 constituents and eight inflammatory biomarkers (fibrinogen, C-reactive protein, monocyte chemoattractant protein-1, tumor necrosis factor-α, interleukin-1b, intercellular adhesion molecule-1, P-selectin, vascular cell adhesion molecule-1) and two coagulation biomarkers (plasminogen activator inhibitor-1 and soluble CD40 ligand). We found robust associations of organic carbon (OC), elemental carbon (EC), nitrate (NO₃^-), and ammonium (NH₄⁺) with at least 1 of 8 inflammatory markers. On average, an interquartile range increase in the four constituents corresponded to increments of 50%, 37%, 25%, and 26% in inflammatory biomarkers, respectively. Only sulfate (SO₄^2-) or NH₄⁺ was robustly associated with coagulation markers (corresponding increments: 23% and 20%). Our results provided evidence that some constituents in PM_2.5 (OC, EC, NO₃^-, SO₄^2-, and NH₄⁺) might play crucial roles in inducing systematic inflammation and coagulation, but their roles varied by the selected biomarkers.