2.5. In vitro cytotoxicity
Cytotoxicity of TPM and the water soluble constituents of the gas/vapor phase (GVP) of MS was assessed with the Neutral Red Uptake (NRU) assay (Borenfreund and Puerner, 1985, 1987) with mouse embryo BALB/c 3T3 cells as previously described (Roemer et al., 2009).