The typical daily dietary intake of cadmium is 10 to 20 µg. Significant sources of cadmium include shellfish, grains (especially those grown on high cadmium soils) and leafy vegetables. Cadmium has a long half-life in the body and thus high intakes can lead to accumulation resulting in damage in some organs, especially the kidney. The Reference Dose (RfD) (safe daily intake over a lifetime) for cadmium is 0.5 µg per kg body weight.