Fig. 4From: The effects of facemasks on airway inflammation and endothelial dysfunction in healthy young adults: a double-blind, randomized, controlled crossover studyBiomarker concentrations of the subjects in 4 tests. 1*: pre-exposure; 2*: 15-min post-exposure; 3*: 6-h post-exposure; 4*: 24-h post-exposureBack to article page