The present study aimed to analyze the impact of environmental contamination on metal accumulation and oxidative stress in wild rats, Rattus rattus, collected from metal-polluted areas in the vicinity of Riyadh Region, Saudi Arabia.Soil samples and wild rats were collected from four locations (Dhurma, Kharj Road, Al Muzahmiyah and Laban Valley ) that differ in their extent of pollution load. However, Laban Valley was taken as a reference site in this study . High concentrations of heavy metals (cadmium, lead and zinc) were recorded in soil and tissues ( liver, kidney and hair) of animals collected from Dhurma , the site with high anthropogenic pressure. Moreover, a significant increase in the level of liver malondialdeyhde (MDA) coupled with an inhibition of the activity of superoxide dismutase (SOD), catalase (CAT), Glutathione Peroxidase(GPx), Glutathione Reductase (GR) and Glutathione-S-Transferase (GST) were recorded in Dhurma followed by Kharj Road and Al Muzahmiyah compared to the reference site.From these results , it could be concluded that that the selected biomarkers are useful for the assessment of pollution impacts in natural environments and the small wild animal R. rattus can be used as a bioindicator model for metal toxicity in an arid environment
