The effect of the CNT panel on cell viability. The viability of mesothelial cells was measured by trypan blue exclusion (A) and LDH release (B) after a 24 hour exposure to the CNT panel, UT indicates untreated control. LDH release was also used as an indicator of cell viability of macrophages at 24 hours after CNT treatment (C). Data expressed as a mean ± sem, n = 3. Significance versus vehicle control *** indicates p < 0.001.