Greenhouse experiments were conducted to determine whether Arabidopsis thaliana (L.) Heynh., a putative Fe-efficient species, accumulated higher concentrations of Cd from a sparingly soluble Cd source (cadmium dihydrogen phosphate) when growing in Fe-deficient rather than in Fe-sufficient conditions. Analysis of the uptake of other elements by Arabidopsis suggests that the greater accumulation of Cd by plants in the Fe-deficient treatment may be a consequence of the species' Fe efficiency mechanisms. Our results support the hypothesis that uptake of toxic elements by Fe-efficient species can be enhanced when the plants are growing in Fe-deficient soils.