Journal Article

Effect of wood smoke exposure on vascular function and thrombus formation in healthy fire fighters

Flapan, Andrew D, Sadiktsis, Ioannis, Unosson, Jon, Lucking, Andrew J, Langrish, Jeremy P, Mills, Nicholas L, Boman, Christoffer, Shah, Anoop SV, Newby, David E, Pourazar, Jamshid, Bosson, Jenny A, Nyström, Robin, Masala, Silvia, Pung, Louis, Raftis, Jennifer B, Sandström, Thomas, Westerholm, Roger, Donaldson, Kenneth, Miller, Mark R, Hunter, Amanda L, Blomberg, Anders

2014

Overview

Background Myocardial infarction is the leading cause of death in fire fighters and has been linked with exposure to air pollution and fire suppression duties. We therefore investigated the effects of wood smoke exposure on vascular vasomotor and fibrinolytic function, and thrombus formation in healthy fire fighters. Methods In a double-blind randomized cross-over study, 16 healthy male fire fighters were exposed to wood smoke (~1 mg/m 3 particulate matter concentration) or filtered air for one hour during intermittent exercise. Arterial pressure and stiffness were measured before and immediately after exposure, and forearm blood flow was measured during intra-brachial infusion of endothelium-dependent and -independent vasodilators 4–6 hours after exposure. Thrombus formation was assessed using the ex vivo Badimon chamber at 2 hours, and platelet activation was measured using flow cytometry for up to 24 hours after the exposure. Results Compared to filtered air, exposure to wood smoke increased blood carboxyhaemoglobin concentrations (1.3% versus 0.8%; P < 0.001), but had no effect on arterial pressure, augmentation index or pulse wave velocity (P > 0.05 for all). Whilst there was a dose-dependent increase in forearm blood flow with each vasodilator (P < 0.01 for all), there were no differences in blood flow responses to acetylcholine, sodium nitroprusside or verapamil between exposures (P > 0.05 for all). Following exposure to wood smoke, vasodilatation to bradykinin increased (P = 0.003), but there was no effect on bradykinin-induced tissue-plasminogen activator release, thrombus area or markers of platelet activation (P > 0.05 for all). Conclusions Wood smoke exposure does not impair vascular vasomotor or fibrinolytic function, or increase thrombus formation in fire fighters. Acute cardiovascular events following fire suppression may be precipitated by exposure to other air pollutants or through other mechanisms, such as strenuous physical exertion and dehydration. Trial registration ClinicalTrials.gov Identifier: NCT01495325 .

• Publisher: BioMed Central,BioMed Central Ltd
• Subject: Adult / Air pollution / Bicycling / Biomarkers - blood / Biomarkers - metabolism / Biomedical and Life Sciences / Biomedicine / Cross-Over Studies / Double-Blind Method / Endothelium, Vascular - drug effects / Endothelium, Vascular - immunology / Endothelium, Vascular - metabolism / Endothelium, Vascular - physiopathology / Environmental Health / Fire-fighters / Firefighters / Humans / Male / Nanotechnology / Pharmacology/Toxicology / Platelet Activation - drug effects / Pneumology/Respiratory System / Public Health / Risk / Scotland - epidemiology / Smoke - adverse effects / Smoke Inhalation Injury - blood / Smoke Inhalation Injury - immunology / Smoke Inhalation Injury - metabolism / Smoke Inhalation Injury - physiopathology / Thrombosis / Thrombosis - epidemiology / Thrombosis - etiology / Vascular Diseases - epidemiology / Vascular Diseases - etiology / Vascular function / Vascular Stiffness - drug effects / Vasomotor System - drug effects / Vasomotor System - immunology / Vasomotor System - metabolism / Vasomotor System - physiopathology / Wood / Wood smoke / Young Adult