Figure 1.

Evaluation of the cytotoxic potential of B[a]P in RT4 cells: To determine the potential of B[a]P to initiate cytotoxic effects in human bladder epithelial cells, various endpoints were measured, including formation of reactive oxygen species (ROS, A), apoptosis (TUNEL assay, B), cell proliferation (EdU, C). Cells were cultured on 96-well plates with a clear bottom and were exposed to different concentrations of B[a]P (0.1 to 100 µM) for 24 h. H₂O₂ (100 µM) was used as positive control in ROS assay, while a TUNEL-positive control was obtained by incubation with DNase I. In control, cells were exposed to DMSO (<0.1%). The data is presented as mean ± standard deviation of four independent experiments with RT4 cell lysates. The level of significance relative to the control was determined by using the t-test (*p < 0.05, ***p < 0.001).