Background: Workers are occupationally and environmentally exposed to diverse forms of xenobiotics as gases and vapors. Career publicity to those compounds can trade the prooxidants/oxidants and antioxidants equilibrium throughout oxidative toxic stress (OTS). Pollutants might also cause genotoxicity by oxidative DNA. This work was conducted in AL-Nasiriya at the Thi-Qar Oil refinery in Thi-Qar province, south of Iraq. Samples have been amassed from the refinery workers and Campus college students and workforce as control. Seventy blood samples from the refinery people running within the asphalt, laboratory, and refining units and samples from Campus students and staff as control have been collected. The 8- OHDG was measured using the ELISA technique. The serum 8- OHdG of refinery workers was notably higher than that of individuals of control subjects (p< 0.001*). A higher level of serum 8-OHdG was quantified in the blood samples of all exposed subjects. The significant feature that resulted in an enhanced genotoxic potential was the years of exposure to the oil refinery environment, which led to an increase in the 8-OHdG formation. Keywords: Genotoxicity ; workers occupationally ; pollutants ; Dhi- Qar ; oil refinery