Brain concentrations of Cu, Mg, Zn, Al, Cd and Pb in wild populations of the African rat (Arvicanthus niloticus) collected from a highly polluted industrial area in Cairo, Egypt were evaluated in the present study. The neurotoxic effects and histopathological alterations resulting from continued metal exposure were considered in this study. Biochemical markers of the redox balance, e.g. superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione-S-transferase (GST), glutathione peroxidase (GP_X), and acetylcholinesterase (AChE) activities and malondialdehyde (MDA) content, were measured. Compared with the control animals from Abu Rawash, a highly significant increase in brain Mg (219 versus 126 μg/g dry weight), Zn (22.6 versus 3.44 μg/g dry weight) and Al (0.317 versus not detectable μg/g dry weight) were detected in the African rat (A. niloticus) collected from the polluted site. However, antioxidant defence system in animals exposed to metal pollution showed no significant increases with the exception of GST (923 versus 816 μmol/min/mg protein) and GP_X (1108 versus 891 μmol/min/mg protein) activities. A similar increase was noticed for MDA (4.40 versus 3.13 μmol/min/mg protein), while cholinesterase showed less activity in specimens collected from the polluted area in comparison to specimens collected from the reference site (62.6 versus 125 μmol/min/mg protein). The histopathological alterations were observed in the brain tissues of specimens trapped from the polluted area in comparison to those collected from the reference area.