Objective: To investigate the associations between exposure to particulate air pollution and changes in cardiovascular function and plasma mediators in seniors.

Methods: We monitored daily indoor and outdoor black carbon and particulate matter <=2.5um (PM2.5) and personal PM2.5 repeatedly for 28 nonsmoking seniors. We then measured their blood pressure, heart rate, and brachial artery function, and determined plasma mediators of inflammation, vascular function, and oxidative stress. We tested associations using mixed-effects models.

Results: Increases in black carbon and PM2.5 were associated with increases in blood pressure, heart rate, endothelin-1, vascular endothelial growth factor, and oxidative stress marker thiobarbituric acid reactive substances, and a decrease in brachial artery diameter (P<0.05).

Conclusion: Daily exposure to particulate pollution, likely trafficrelated, may result in adverse effects on cardiovascular function and blood mediators that modulate vascular system in seniors.