Cadmium (Cd) works by disrupting the normal state of a cell. Its similar structure to zinc and calcium allows it to interfere with the absorption of these elements, and it similarly inhibits copper and iron. Like most heavy metals, when absorbed into the body cadmium is stored in the liver and kidney of the animal. Cadmium is an accumulative poison, meaning that it builds up slowly over time in the bodies of exposed animals. Cadmium poisoning affects nearly all major organ systems and has noted reproductive effects, including decreased testes size and infertility. Additionally, because of this element's interference with the absorption of the mineral calcium, cadmium poisoning can also severely impact the healthy function of the bones. Though cadmium is extremely rare in the Earth's crust, pollution from industry processes has allowed this toxic metal access into soils and water supplies.