Americium - Am
Americium (Am)
Americium is a radioactive, synthetic actinide. Americium-241 is the most familiar isotope and is produced in nuclear processes; the element is not found in appreciable natural quantities.
| Atomic number | 95 |
|---|---|
| Representative isotope mass number | [243] (representative isotope mass number) |
| Electron configuration | [Rn] 5f7 7s2 |
| Density | 12.0 (reported) g/cm3 |
| Melting point | 1176 °C |
| Boiling point | 2011 °C |

Uses and applications
Small, sealed americium-241 sources are used in some ionization smoke detectors. Americium is also used in specialised industrial gauges and research instruments. These sources are designed for controlled use and must be managed through approved radiation-safety and disposal systems.
Americium and water management
Americium is not a water-treatment reagent. If detected in water associated with nuclear, medical, or research activities, it requires radionuclide-specific sampling and radiological controls; do not infer its risk from total dissolved-metal measurements alone.
Occurrence and environmental context
Americium is an actinide, and its occurrence and environmental behaviour depend on isotope, chemical form, and source. Natural geology, mineral processing, and nuclear-related activities can each affect whether an actinide is present in a water or waste stream. Monitoring should distinguish chemical concentration from radioactive activity where relevant.
Health and safety
Americium requires careful handling because of its radioactive properties; for some elements, chemical toxicity is also relevant. Exposure depends on isotope, activity, chemical form, and route. Follow applicable radiation-protection procedures and substance-specific safety information.
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Sources and further reading
Element page last reviewed: 24 October 2026 by Lenntech.