Anthropogenic cadmium is increasing the cadmium concentration in herbage consumed by ruminants. It is derived mainly from phosphate fertilisers and mineral mixes added to concentrates, but in future sewage sludge applications to pasture may be more important. It has the potential to damage the health of the ruminants and ultimately the humans that consume their contaminated products, in particular offal. Cadmium is initially complexed by metalloproteins in the liver, extracted from the blood by the kidney and excreted in urine. In severe cases it impairs the reabsorption capabilities of the proximal tubules of the kidney. Although many clinical studies have been conducted with provocative levels of cadmium fed to laboratory animals, little is known about the potential for typical levels of cadmium in mildly contaminated feed to cause kidney damage in sheep.