| Some like americium, iodine 129 or cesium 135 can remain several hundred millenia. |
| Alpha particles emitted by the americium ionize the air, making the air conductive. |
| Although plutonium isotopes and americium 241 will persist perhaps for thousands of years, their contribution to human exposure is low. |
| Internal contamination with plutonium, americium, or curium can occur through a variety of routes including ingestion, inhalation, or direct contact through wounds. |
| When americium was used as a target in this research, evidence for the formation of a new element was obtained. |
| Metallic californium has been prepared and is structurally similar to metallic americium, curium, berkelium, and most lanthanoid metals. |
