Fig. 1

Viability of TT1, AT2 and MAC following 24 h exposure to 50 nm and 100 nm polystyrene nanoparticles. 50 nm ANPs, at 50-100 μg/ml, caused significant cell death in all cell types (a, c, e). 100 nm ANP, 50 and 100 μg/ml, caused significant cell death in AT2 and MAC but not TT1 cells (b, d, f). Addition of antioxidant N-acetylcysteine (NAC), 10 mM, did not prevent TT1 cell death (g), whereas NAC protected AT2 and MAC from the effects of low concentrations of ANPs (h-i). UNP and CNP had no effect on cell viability. *p < 0.05, **p < 0.001 and n = 3 TT1 replicates and n = 6 subject samples for AT2 and MAC