Figure 4. HMGECs were differentiated for 48 h before exposure to BAK for 3 h. At 20 and 200 µg/ml, BAK was lethal to the HMGECs. There were nine replicates per condition. BAK: benzalkonium chloride; TX100: Triton-X 100 positive control; Gray bar: p ≤ 0.05; Black bar: p ≤ 0.01; Dashed bar: p ≤ 0.001.