Assessment of DNA damage and oxidative stress among traffic conductors and coal miners

OBJECTIVE: To assess the DNA damage and oxidative stress among traffic conductors and coal miners. METHODS: An analytical cross-sectional survey was conducted in Karak, Pakistan from March to October 2019. A total of 240 individuals participated in the study with an age range between 17 to 55 years. Among the total sample, 60 participants had exposure to traffic pollution while 60 were mine workers. Two control groups, consisting of 60 individuals each, were also recruited for comparison with the two exposure groups. Comet assay protocols were performed for assessing DNA damage and oxidative stress (length of DNA tail, levels of Superoxide Dismutase (SOD), Malondialdehyde (MDA) and Glutathione (GSH)). Data was analyzed using T-test on statistix 9.0 software. RESULTS: The DNA tail length in traffic conductors ranged from 26.83-30.55µm (Mean=28.69 µm while their control group had DNA tail length of 7.98-9.26µm (Mean= 8.62). There was significant difference (P <0.001) between exposure and control group. The DNA length recorded in coal mine workers and their control group was ranged from 29.06-31.26µm (Mean=30.16µm) and 9.42-10.22µm (Mean=9.82), respectively. There was significant difference (P <0.001) between the two groups. As compared to control groups, both exposure groups have high levels of Superoxide Dismutase and Malondialdehyde and low levels of Glutathione. The finding was statistically significant (P <0.001). CONCLUSION: Increased inhalational exposure to air pollutants via working in traffic or coal mines can impose higher oxidative stress and DNA damage among workers as compared to the general population.