Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Randomized Controlled Trial
, 176 (4), 395-400

Persistent Endothelial Dysfunction in Humans After Diesel Exhaust Inhalation

Randomized Controlled Trial

Persistent Endothelial Dysfunction in Humans After Diesel Exhaust Inhalation

Håkan Törnqvist et al. Am J Respir Crit Care Med.


Rationale: Exposure to combustion-derived air pollution is associated with an early (1-2 h) and sustained (24 h) rise in cardiovascular morbidity and mortality. We have previously demonstrated that inhalation of diesel exhaust causes an immediate (within 2 h) impairment of vascular and endothelial function in humans.

Objectives: To investigate the vascular and systemic effects of diesel exhaust in humans 24 hours after inhalation.

Methods: Fifteen healthy men were exposed to diesel exhaust (particulate concentration, 300 microg/m(3)) or filtered air for 1 hour in a double-blind, randomized, crossover study. Twenty-four hours after exposure, bilateral forearm blood flow, and inflammatory and fibrinolytic markers were measured before and during unilateral intrabrachial bradykinin (100-1,000 pmol/min), acetylcholine (5-20 microg/min), sodium nitroprusside (2-8 microg/min), and verapamil (10-100 microg/min) infusions.

Measurements and main results: Resting forearm blood flow, blood pressure, and basal fibrinolytic markers were similar 24 hours after either exposure. Diesel exhaust increased plasma cytokine concentrations (tumor necrosis factor-alpha and interleukin-6, p < 0.05 for both) but appeared to reduce acetylcholine (p = 0.01), and bradykinin (p = 0.08) induced forearm vasodilatation. In contrast, there were no differences in either endothelium-independent (sodium nitroprusside and verapamil) vasodilatation or bradykinin-induced acute plasma tissue plasminogen activator release.

Conclusions: Twenty-four hours after diesel exposure, there is a selective and persistent impairment of endothelium-dependent vasodilatation that occurs in the presence of mild systemic inflammation. These findings suggest that combustion-derived air pollution may have important systemic and adverse vascular effects for at least 24 hours after exposure.

Comment in

Similar articles

See all similar articles

Cited by 117 PubMed Central articles

See all "Cited by" articles

Publication types

MeSH terms