Experimental woodsmoke exposure during exercise and blood oxidative stress

Objectives: The current laboratory study quantified blood oxidative stress to woodsmoke exposure. Methods: Participants inhaled woodsmoke during three randomized crossover exercise trials (Clean Air [0 mg/m³], Low Exposure [250 mg/m³], and High Exposure [500 mg/m³], Woodsmoke [particulate matter less than 2.5 mm, PM_2.5]). Trolox equivalent antioxidant capacity (TEAC), uric acid (UA), 8-isoprostanes (8-ISO), lipid hydroperoxides (LOOH), protein carbonyls (PC), nitrotyrosine (3-NT), 8-isoprostane, and myeloperoxidase (MPO) were quantified in Pre, immediately Post, and 1- (1Hr) hour post blood samples. Results: UA decreased following Low Exposure, while plasma TEAC levels increased Post and 1Hr. LOOH levels decreased 1Hr Post (High Exposure), while 8-Iso increased following both smoke trials. PC and MPO were unchanged following all trials, while 3-NT increased over Clean Air. Conclusion: Blood oxidative stress occurred largely independent of PM_2.5 concentrations. Future studies should employ longer duration smoke and exercise combined with physiologic parameters.