It was observed that decreasein cell viability after treatment with organic extracts of urban station samples at a concentration of 100 μg/mL was four times higher than that at a concentration of 25 μg/mL for an incubation time of 12 h. The cell viabilities for organic and water-soluble extracts of suburban station samples (with an incubation time of 24 h and a concentration of 100 μg/mL) were 61% and 68%, respectively (Fig. 10b). Statistical analysis revealed a significant difference between the urban and suburban station samples in terms of the percentage of viable cells, whereas no statistically significant differencewas observed between urban and traffic station samples (p > 0.05). substances bound on the particle surface, such as PAHs, nitro-PAHs, and metals (Naimabadi et al., 2016). No statistically significant difference in cell viability was observed at an incubation time of 12 h for the cytotoxicity induced by the water-soluble fractions from the three stations at low concentrations (p > 0.05) (Meng and Zhang, 2007).