The Role of CYP4502E1 Genetic Polymorphism on Benzene Metabolism

The carcinogenic effect of benzene is associated with metabolites produced in benzene metabolism such as phenol, catechol, quinones, muconic acid (tt-MA), and phenyl mercapturic acid (s-PMA). The role of CYP4502E1 enzyme in benzene metabolism is very important, which is determined by its genetic polymorphism. This cross-sectional study is aimed to obtain the distribution of frequency of s-PMA concentration in workers who had been low exposure of benzene based on CYP4502E1 genetic polymorphism. The study was conducted between September 2007 and April 2010. Data were collected by methods of interviews, physical examinations, laboratory examinations, and direct observation on the work place. The variables studied were CYP4502E1, benzene exposure at the work place, age, type of work, history of work, length of work, body mass index (BMI), antioxidants intake, behavior and management, and s-PMA concentration in the urine. The distribution of CYP4502E1 genetic polymorphism in workers is 87.8% wild type homozygote, 11.3% heterozygote and 0.9% mutant homozygote. There was no significant difference in the proportion of s-PMA concentration based on CYP4502E1 genetic polymorphism (p=0.595; ORraw=0.98; 95% CI=0.95-1.01). There were also no differences of age, type of work, length of work, BMI, antioxidants consumptions, behavior and management of subjects with s-PMA. Further study should be conducted on CYP4502E1 genetic polymorphism in various Indonesian races at different workplace with low-level benzene.