Cell survival fractions of HaCaT cells treated with HgCl2 at different concentrations. The cell survival fractions were 38.08, 17.59, 12.76, 3.29 and 0.77% when the keratinocytes were treated with 0.25, 0.5, 0.75, 1 and 1.5 μM of HgCl2, respectively.