Fig. 2

Time course in the XTT assay (OD at 450–650 nm). HTR-8/SVneo cells were treated with anthracene, benzo[k]fluoranthene, benzo[a]pyrene, and 4,4-(9-fluorenylidene)diphenol at 24, 48, and 72 h for the time course analysis using XTT assay. Treatment of the cells with anthracene (50 µg/mL) showed an initial absorbance of 1.517 ± 0.011, which showed a decreasing tendency with increasing time, decreasing to 1.402 ± 0.068 at 24 h, 1.097 ± 0.132 at 48 h, and 0.568 ± 0.141 at 72 h. The OD values obtained following 300 µg/mL benzo[k]fluoranthene treatment for 24, 48, and 72 h were also lower than the initial value. The absorbance following treatment with benzo [a]pyrene at a concentration of 100 μg/mL showed a decrease after 24 h. Similar results were observed when the cells were treated with 5 µg/mL of 4,4-(9-fluorenylidene)diphenol. Compared with the initial OD value, the absorbance was lower than that of the control at 24 h, 48 h, and 72 h