Fig. 3

Carbon loading in alveolar macrophages and lung function parameters. Carbon uptake areas in BALF macrophages (A, red arrows) following DEP exposures for 2-wk, 4-wk and 8-wk significantly increased, in a dose-dependent manner, compared to carbon uptake areas following filtered air exposure (*** p < 0.001, ## p < 0.01, ### p < 0.001, B). Bar = 8 μm. Total lung capacity (TLC) increased significantly following 2-wk, 4-wk and 8-wk DEP exposures as compared to filtered air controls, respectively (** p < 0.01, C). Also, lung resistance increased significantly following 4-wk and 8-wk DEP exposures, respectively (** p < 0.01, D). Data were expressed as mean (95% CI). ns = not significant