Fig. 4

Colony forming efficiency (CFE) in human lung epithelial A549 cells after exposure to NMs. Data are presented as mean values from 3 independent experiments (with two technical replicates in each independent experiment) + / − SD, relative to negative control (NC). Statistically significant difference respect to NC according to one-way ANOVA with Dunnett’s post-hoc test, *p < 0.05, **p < 0.01, *** p < 0.001