Uranium and such compounds as uranium hexafluoride and tetraflouride, can also act as a chemical toxin, killing off cells in the liver and kidney. Polonium, a radioactive decay product of radon that is used to trigger chain reactions in nuclear weapons, behaves differently than uranium. Although polonium exposure is likely to occur by inhaling dust particles in the air, polonium doesn't settle in the lungs as uranium does. It filters into the blood where it is carried throughout the body. Because it travels throughout the body, polonium has been linked to more soft-tissue than bone cancers.
Typical sites are the liver, spleen and kidney.
Thorium, used in nuclear reactors producing enriched uranium and plutonium, concentrates in the lungs and in focal points in bone. Radium, a common byproduct of uranium refining, gives off radon gas. Radon gas is highly cardinogenic. Most radioactive substances will increase the risk of cancer in a population by 1 case per thousand people. Radon hikes the lifetime risk of lung cancer to 1 in 100.