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A man-made, radioactive metal with a melting point of 1173 degrees C; [Merck Index] ". . . a silvery, ductile, very malleable, non-magnetic metal." [ATSDR ToxProfiles]


Americium is a byproduct of plutonium production in nuclear reactors. Americium-241 is used in smoke detectors and in industrial radiography; Also used with beryllium as a neutron source, and as a target material in nuclear reactors and accelerators to synthesize heavier elements; [Argonne] Used in medical diagnosis as a bone mineral analyzer; Used as a radiation source in the treatment of cancer; [Merck Index] A typical household smoke detector contains about 0.9 uCi of Am-241. [ATSDR ToxProfiles]


Most Important Radionuclide: Am-241; Source: Beta decay of plutonium-241; Half-Life: 430 years; Effective Half-Life: 139 years; Specific Activity: 3.5 Ci/g; Decay Mode: Alpha; GI Absorption: 0.05%; Lung Clearance Half-Time: 10-100 days for all compounds; Critical Organ: Bone; Internal Toxicity: Very High; Annual Limit on Intake: 0.000006 mCi; Tenth-Value Layer: 0.4 mm Pb; Gamma Ray Constant: 0.1 R/h @ 1 cm per mCi; Radiation Energy (MeV): Alpha 5.48 (85%); Gamma 0.0595 (38%) Radiation Accidents: 3 accidents including one at Hanford in 1976 in which worker survived a >1 mCi dose; 3 incidents of "Melting of Radioactive Materials"; [See Glossary for references.] See "Radiation, ionizing."

Reference Link

ATSDR - Public Health Statement: Americium

Exposure Assessment
Reference Link

Americium | Radiation Protection | US EPA

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