author(s)
Muhammad Ateeq, Hameed Ur Rehman, Shehzad Zareen, Abdul Rehman, Wajid Ullah, Muhammad Shah, Aina Bibi, Sairish Habib, Mujaddad-ur-Rehman and Ziafat Rehman

abstract
Trivalent chromium is extensively used in tanning process which appears to be associated with genetic damages in workers. Therefore, the present study was undertaken to investigate the oxidative stress parameters and DNA damage in chromium exposed tanners. DNA damage in lymphocytes was measured by the comet assay. The results showed that blood chromium, DNA damage, superoxide dismutase (SOD) and malondialdehyde (MDA) levels were significantly higher (p<0.001), while glutathione (GSH) level was significantly lower (p<0.001) in exposed groups as compared to control group. In Pearson correlation analysis, blood chromium level showed significant correlation with oxidative stress parameters and DNA damage. The mean tail length of two exposure groups was significantly higher as compared to control. These findings showed that during long-term chromium exposure, chromium is absorbed in the body, which may be distributed in the various tissues and organs of exposed workers. The present study revealed that occupational exposure to trivalent chromium can lead to oxidative stress and DNA damage in tannery workers. DNA damage and blood chromium level may serve as an efficient biomarker in tannery workers exposed to trivalent chromium.