Oxidative DNA Damage Estimated by Plasma 8-hydroxydeoxyguanosine (8-OHdG)：Influence of 4, 4'-methylenebis (2-chloroaniline) Exposure and Smoking

• Published in: Journal of Occupational Health 2007-09, Vol.49 (5), p.389-398
• Main Authors: Chen, Hong‐I, Liou, Saou‐Hsing, Ho, Shu‐Fen, Wu, Kuen‐Yuh, Sun, Chien‐Wen, Chen, Ming‐Fong, Cheng, Li‐Chuan, Shih, Tung‐Sheng, Loh, Ching‐Hui
• Format: Article
• Language: English
• Subjects: 4’‐methylenebis (2‐chloroaniline) (MBOCA); 8hydroxydeoxyguanosine (8‐OHdG); Adult; Age Distribution; Air Pollutants, Occupational - analysis; Air Pollutants, Occupational - toxicity; Alcohol Drinking - epidemiology; Biomarkers - blood; Biomarkers - urine; Body Mass Index; Chromatography, Liquid; Confounding Factors (Epidemiology); Cross-Sectional Studies; Deoxyguanosine - analogs & derivatives; Deoxyguanosine - blood; DNA Damage - drug effects; DNA Damage - physiology; Dose-Response Relationship, Drug; Humans; Linear Models; Liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS); Male; Methylenebis(chloroaniline) - analysis; Methylenebis(chloroaniline) - toxicity; Middle Aged; Occupational Exposure - adverse effects; Occupational Exposure - analysis; Oxidative DNA damage; Oxidative Stress - drug effects; Oxidative Stress - physiology; Sex Distribution; Smoking; Smoking - adverse effects; Smoking - epidemiology; Surveys and Questionnaires; Taiwan - epidemiology
• ISSN: 1341-9145; 1348-9585; 1348-9585
• DOI: 10.1539/joh.49.389

Oxidative DNA damage may play an important role in the human carcinogenic process. Recently, we reported a case of bladder cancer among 4,4'-methylenebis (2chloroaniline) (MBOCA)-exposed workers. By measuring the plasma level of 8-hydroxydeoxyguanosine (8-OHdG), we investigated the association between oxidative DNA damage and MBOCA exposure. In addition, we examined the effects of different confounders on the plasma level of 8-OHdG. We undertook a cross-sectional survey at four MBOCA-producing factories in Taiwan (158 subjects). Plasma 8-OHdG levels and urinary MBOCA concentrations were measured by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS). Personal characteristics were collected by questionnaire. The workers were classified according to their job titles as exposed (n=57) or unexposed (n=101) groups as well as classified according to urinary MBOCA levels as high urinary MBOCA (>20μg/g creatinine) (n=45) or low urinary MBOCA (n=108) groups. Neither the MBOCA-exposed workers nor the high urinary MBOCA workers had a significant increase in the mean plasma 8-OHdG level, even after adjustment for potential confounders. Age and gender were significantly positively correlated with plasma 8-OHdG levels. Smokers among high urinary MBOCA workers also had significantly higher 8-OHdG levels than non-smokers among high urinary MBOCA workers. Our study provides evidence that smoking rather than MBOCA exposure induces elevation of plasma 8-OHdG levels among workers exposed to MBOCA, indicating that oxidative DNA damage does not play an important role in the carcinogenic processes of MBOCA.