Iodine: Difference between revisions
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== Radioactive iodine-131 == | == Radioactive iodine-131 == | ||
<sup>131</sup>I | Several [[isotope]]s of iodine, including <sup>123</sup>I, <sup>124</sup>I, <sup>129</sup>I and <sup>131</sup>I are [[radioactive]] [[isotope]]s of iodine used to treat certain [[cancer]]s or for medical imaging processes <ref>http://www.nejm.org/doi/full/10.1056/NEJMoa041511#t=articleBackground</ref><ref>http://www.medscape.com/viewarticle/477675</ref> and <sup>131</sup>I may be acidentally released by [[nuclear energy]] facilities in times of disaster. <sup>131</sup>I can be produced in one of two ways: 1) by nuclear fusion for medical uses, or 2) as a by-product of nuclear fission in nuclear energy facilities. In fact, both <sup>129</sup>I and <sup>131</sup> are produced by fission reactions of uranium in nuclear energy facilities or by detonation of nuclear weapons. I are produced by the fision of uranium <sup>131</sup>I has a [[half-life]] of only 8.06 days<ref>http://www.bt.cdc.gov/radiation/isotopes/pdf/iodine.pdf</ref>, so environmental spills are of much less concern that similar spills of other radioactive elements such as [[cesium]] or [[uranium]]. However, <sup>129</sup>I has a half-life of 15.7 million years.<ref>http://www.epa.gov/radiation/radionuclides/iodine.html#wheredoes</ref> Thus, a spill of <sup>131</sup>I one thousand times the normal background would decay back to normal levels in about 81 days. The <sup>129</sup>I and <sup>131</sup>I atoms emit [[beta particle]]s and emit [[gamma radiation]] during radioactive decay. Because iodine is readily absorbed by the thryroid gland, which uses it to produce [[thyroid hormone]]s, ingestion of radioactive iodine can lead to thyroid pathology, including thyroid cancer. | ||
== Ingestion == | == Ingestion == | ||
Revision as of 18:48, 4 April 2011
Iodine is a chemical element, having the chemical symbol I.
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Its atomic number (the number of protons) is 53. It has a Standard Atomic Weight of 126.90447(3), and is typically found as a solid in its elemental form.
Iodine is considered to be a member of the "Halogen" class of elements, has a boiling point of 184.4 °C , and a melting point of 113.7 °C .
Iodine is specified as a List I chemical by the US Drug Enforcement Administration and is considered to have high risk of diversion to illicit drug manufacturing.[1]
Radioactive iodine-131
Several isotopes of iodine, including 123I, 124I, 129I and 131I are radioactive isotopes of iodine used to treat certain cancers or for medical imaging processes [2][3] and 131I may be acidentally released by nuclear energy facilities in times of disaster. 131I can be produced in one of two ways: 1) by nuclear fusion for medical uses, or 2) as a by-product of nuclear fission in nuclear energy facilities. In fact, both 129I and 131 are produced by fission reactions of uranium in nuclear energy facilities or by detonation of nuclear weapons. I are produced by the fision of uranium 131I has a half-life of only 8.06 days[4], so environmental spills are of much less concern that similar spills of other radioactive elements such as cesium or uranium. However, 129I has a half-life of 15.7 million years.[5] Thus, a spill of 131I one thousand times the normal background would decay back to normal levels in about 81 days. The 129I and 131I atoms emit beta particles and emit gamma radiation during radioactive decay. Because iodine is readily absorbed by the thryroid gland, which uses it to produce thyroid hormones, ingestion of radioactive iodine can lead to thyroid pathology, including thyroid cancer.
Ingestion
Like bromine, iodine is readily sublimed, going from the solid state directly to the gaseous state,(skipping the liquid state) so exposure to the solid form can still lead to inhalation of the chemical. Being a halogen, it also readily forms many salts which are readily soluble, so the molecular form is quickly converted into various salts upon reaction with most environments. Dairy animals exposed to any form of radioactive iodine can thus lead to ingestion by humans.
- ↑ http://www.deadiversion.usdoj.gov/fed_regs/rules/2007/fr0702.htm
- ↑ http://www.nejm.org/doi/full/10.1056/NEJMoa041511#t=articleBackground
- ↑ http://www.medscape.com/viewarticle/477675
- ↑ http://www.bt.cdc.gov/radiation/isotopes/pdf/iodine.pdf
- ↑ http://www.epa.gov/radiation/radionuclides/iodine.html#wheredoes