Exposure to air pollution is associated with increased cardiovascular risk but the mechanisms are poorly understood.     The aim of this investigation was to assess the effect, in rats, of intratracheal instillation of particulate air pollution on leucocyte activation and damage to the vascular endothelium.  Rats were exposed to particulate air pollution by intratracheal instillation of PM10.  Blood was collected 3 days and 6 weeks post instillation.  Plasma neutrophil elastase, von Willebrand factor (vWF) and ICAM-1 were determined by ELISA.  Plasma neutrophil elastase increased from baseline.  There was a statistically significant increase in both von Willebrand factor (p=0.006, ANOVA) and sICAM-1 (p=0.009, ANOVA)  We conclude that lung exposure to particulate air pollution causes systemic inflammation, activation of blood leucocytes and damage to the vascular endothelium.  Inflammatory changes persist long after the initial instillation and exposure to even short term episodes of high levels of particulate air pollution could increase cardiovascular risk.