Association of CYP2E1 and CYP1A1m2 (BsrD1) polymorphisms with cytogenetic biomarkers in petrol pump workers

Petrol pump workers are occupationally exposed to benzene through their contact with gasoline vapors. The toxicity of benzene has been related to its metabolism. This study investigated the association of CYP2E1 and CYP1A1m2 with sister chromatid exchanges (SCE) and tail moment (TM) value in workers occupationally exposed to gasoline fumes. Blood and urine samples were collected from 50 petrol pump workers and 50 control individuals matched with respect to age and other confounding factors except for exposure to benzene through gasoline vapors. To determine the benzene exposure, hydroquinone level was analyzed in urinary samples of exposed and control individuals. Urinary mean hydroquinone level was found to be significantly high (p < 0.05) in exposed workers. Our results showed that mean SCE frequency and TM value were significantly higher (p < 0.05) in exposed workers (5.56 ± 0.80 and 19.50 ± 2.16 μm, respectively) than control individuals (2.83 ± 0.39 and 1.00 ± 0.00 μm, respectively). Regarding the effect of CYP2E1 polymorphism, it was found that mutant genotypes (homozygous and heterozygous) showed significant high mean frequency of SCE (6.11 ± 0.51 and 5.98 ± 0.54, respectively) and TM (16.13 ± 4.36 μm and 13.24 ± 2.24 μm, respectively) value in exposed individuals (p < 0.05). With regard to the CYP1A1m2 polymorphism, it was observed that mutant genotypes (homozygous and heterozygous) had higher but nonsignificant mean value of SCE frequency (5.86 ± 1.07 and 5.86 ± 1.07, respectively) and significantly higher TM value (14.97 ± 3.74 μm and 13.93 ± 2.23 μm, respectively) in exposed individuals.