Fig. 4

In vitro data showing; A: metabolic activity, B: ROS activity, C: genotoxicity and D: Annexin V, a marker of apoptosis. Two cell lines; A549 and BEAS-2B exposed to WSP at four different concentrations (38, 75, 150, 300 µg/mL) for 6 h. Controls were filtered air, blank and DMSO. Data are shown as median with IQR. Some concentrations could not be analysed due to extensive cell death, n.a. indicates not applicable. *indicates p < 0.05, **p < 0.01, and ***p < 0.001