Association of gene polymorphism in detoxification enzymes and urinary 8-OHdG levels in traffic policemen exposed to vehicular exhaust

Abstract

Context: With rapid economic growth and massive development of transportation, the number of automobiles has greatly increased. Traffic police are the one of the vulnerable groups predominantly exposed to vehicular exhaust during traffic control.

Objective The present study is aimed to study the relation between occupational exposure to vehicular exhaust and oxidative stress (OS) in traffic police. We investigated the levels of 8- hydroxydeoxyguanosine (8-OHdG), one of the most sensitive biomarkers for measuring OS and the association between polymorphisms in Cytochrome P450 (CYP) and Glutathione S-Transferase (GST) genes that are known to play a significant role in the activation and detoxification of xenobiotics.

Materials and methods: 148 non smoking male traffic policemen and 135 control subjects were selected for this study. The 8-OHdG levels were analyzed by liquid chromatography with electrochemical detection method. Gene polymorphism was detected by multiplex PCR and RFLP method.

Results: 8-OHdG levels were found to be increased in traffic police with increase in the years of service in traffic control (p = 0.02) when compare to the controls. The results showed a significant increase in urinary 8-OHdG levels in mutated CYP1A1m1 (p < 0.007) and null GSTM1 (p < 0.01) genotypes. However the genotype frequencies of CYP1A1 m2 and GSTT1 genes did not vary in both exposed and control groups.

Conclusion: Our study suggests that exposure to vehicular exhaust over a period of time increases oxidative stress and subsequently induces oxidative DNA damage in traffic policemen. Preventive and therapeutic strategies may be considered for traffic policemen to minimize the adverse effects due to vehicular exposure.

Keywords::

• Traffic police
• vehicular exhaust
• oxidative stress
• gene polymorphism

Acknowledgements

The authors wish to thank all the study subjects who voluntarily participated in the study. We also acknowledge AP Pollution Control Board, Hyderabad for providing air monitoring data.

Declaration of interest

The authors declared no conflict of interest.