231 Actinium-227 Actinium is a radioactive chemical element with the symbol Ac and atomic number 89. Actinium-227 is the naturally occurring radioactive isotope of actinium and has a half-life of 21.772 years. Actinium-227 is also produced in milligram amounts by the neutron irradiation of 226Ra in nuclear reactors. Actinium-227 is an alpha and beta emitter. It is extremely radioactive, and is even more dangerous than plutonium. Ingesting even small amounts would be fatal. (L1131) 14952-40-0 105152 Ac 0.000000 Actinium is a silvery solid metal. Due to its intense radioactivity, actinium glows in the dark with a pale blue light. (L1131) 1323°K (1050°C, 1922°F) 3471°K (3198 °C, 5788 °F) 10 g·cm−3 (room temperature) Oral (L1837) ; Inhalation (L1837) The ionizing radiation produced by actinium causes cellular damage that includes DNA breakage, accurate or inaccurate repair, apoptosis, gene mutations, chromosomal change, and genetic instability. This leads to loss of normal cell and tissue homeostasis, and development of malignancy. Ionizing radiation that does not directly damage DNA can produce reactive oxygen intermediates that directly affect the stability of p53, an important enzyme in cell-cycle regulation, and produce oxidative damage to individual bases in DNA and point mutations by mispairing during DNA replication. (L1837) Internalized radionuclides that emit α or β particles are carcinogenic to humans (Group 1) (L2150). Actinium-227 undergoes alpha and beta decay. Actinium's radioactivity make it a valuable as a neutron source for energy. (L1131) Actinium is extremely radioactive and thus poses a dangerous cancer risk. It can also cause acute radiation syndrome. (L1131) Exposure to high doses of ionizing radiation results in acute radiation syndrome, which can cause skin burns, hair loss, nausea, vomiting, dizziness, disorientation, low blood pressure, headache, fatigue, weakness, fever, birth defects, illness, infection, and death. (L1837, L1852) Treatment reversing the effects of irradiation is currently not possible. Anaesthetics and antiemetics are administered to counter the symptoms of exposure, as well as antibiotics for countering secondary infections due to the resulting immune system deficiency. (L1852) 2009-03-06T18:58:20Z 2014-12-24T20:21:22Z Actinium-227 true [227Ac] Ac InChI=1S/Ac/i1+0 InChIKey=QQINRWTZWGJFDB-IGMARMGPSA-N 227.0277 227.027746979 Exogenous Solid 94864