Plutonium

CAS ID#: 7440-07-5

Affected Organ Systems: Cancer

Cancer Classification:  Please contact NTP, IARC, or EPA with questions on cancer and cancer classification.

Chemical Classification: Radionuclides (radioactive materials)

Summary: Plutonium is a silvery white metal that exists as a solid under normal conditions. It is produced when uranium absorbs an atomic particle. Trace amounts of plutonium occur naturally, but large amounts have been produced in nuclear reactors. Trace levels of plutonium can be found in the environment, from past nuclear bomb tests, in several forms called isotopes. The most common plutonium isotopes are plutonium-238 and plutonium-239. Plutonium undergoes radioactive decay. In this decay process, energy is released and a new product is formed. The energy released is called radiation. When plutonium decays, it divides into two parts-a small part that is called "alpha" radiation and a large part called a daughter. The daughter is also radioactive, and it, too, continues to decay until a nonradioactive daughter is formed. During these decay processes, three types of radiation are released-alpha, beta, and gamma. Alpha particles can travel only a short distance and cannot travel through your skin. Beta particles can penetrate through your skin, but they cannot go all the way through your body. Gamma radiation can go all the way through your body.