The effect of acute exposure to coarse particulate matter air pollution in a rural location on circulating endothelial progenitor cells: results from a randomized controlled study

AbstractContext: Fine particulate matter (PM) air pollution has been associated with alterations in circulating endothelial progenitor cell (EPC) levels, which may be one mechanism whereby exposures promote cardiovascular diseases. However, the impact of coarse PM on EPCs is unknown.Objective: We aimed to determine the effect of acute exposure to coarse concentrated ambient particles (CAP) on circulating EPC levels.Methods: Thirty-two adults (25.9 ± 6.6 years) were exposed to coarse CAP (76.2 ± 51.5 μg m−3) in a rural location and filtered air (FA) for 2 h in a randomized double-blind crossover study. Peripheral venous blood was collected 2 and 20 h post-exposures for circulating EPC (n = 21), white blood cell (n = 24) and vascular endothelial growth factor (VEGF) (n = 16–19) levels. The changes between exposures were compared by matched Wilcoxon signed-rank tests.Results: Circulating EPC levels were elevated 2 [108.29 (6.24–249.71) EPC mL−1; median (25th–75th percentiles), p = 0.052] and 20 h [106.86 (52...