C(VI)-transformed human lung fibroblasts (WTHBF-6) do not have mitochondrial respiratory dysfunction. (A) Mitochondrial respiration profile for WTHBF-6 cells with the relevant injection strategy for the Seahorse Analyzer mitochondrial stress test. (B) Oxygen consumption data for the control WTHBF-6 cells (C52-2 cells) and Cr(VI)-transformed WTHBF-6 cells (T23-3 and T73-3 cells) presented as a baseline percentage to the third oxygen consumption read. (C) Basal respiration, maximal respiration, and spare respiratory capacity for C52-2, T23-3, and T73-3 cells. (D) Proton leak, non-mitochondrial oxygen consumption, and coupled respiration for C52-2, T23-3, and T73-3 cells. (E) Mitochondrial coupling efficiency for C52-2, T23-3, and T73-3 cells. Data are the average of at least three experiments ± SEM. *p < 0.05.