Combined cadmium and elevated ozone affect concentrations of cadmium and antioxidant systems in wheat under fully open-air conditions

► Combined effect of elevated O3 and Cd levels on wheat was studied using the free-air concentration enrichment system. ► Elevated O3 levels result in an increased concentration of Cd in wheat plants grown on Cd-contaminated soils. ► Combined cadmium and elevated O3 have a significantly synergic effect on oxidative stress in wheat shoots.