Cadmium (Cd) is a worldwide occupational and environmental pollutant [1]. Cd toxicity is widely known and studied in many tissues and organs such as testis, kidney, liver, lung and brain [2,3]. On the other hand, zinc (Zn) is a trace element known as coenzyme for many proteins such as methallothionein [4]. To date, very little is known about the role of Cd and Zn in BBB permeability. To study their effects in BBB permeability in vitro, the RBE4 cell line was used and different concentrations of CdCl2 and ZnCl2 wer…