Posted by:
Anonymous User
(
)
Date: March 17, 2011 03:13PM
Here is something I wrote for friends and family:
Iodine tablet panic buying
Overview:
There has been a widespread panic buying of iodine tablets as a result of the nuclear accidents in Japan. This is due to a widespread perception that iodine tablets are an “anti radiation” treatment. This misconception has been spread by news people little understanding of the role of iodine tablets in the event of a nuclear accident.
Iodine in the human body:
Iodine is concentrated in the thyroid glands and is essential to health. An iodine deficiency results in goiter. People who live in coastal areas rarely have an iodine deficiency because iodine is abundant in marine foods such as fish and seaweed. People who live in inland areas are more likely to have an iodine deficiency. This can result in goiter.
http://en.wikipedia.org/wiki/Goitre. Most table salt sold in the United States is “iodized.” This addition of trace amounts of iodine in table salt provides sufficient iodine in the diet of those living in inland areas to prevent goiter. The thyroid glands will accumulate sufficient iodine to function normally; any excess is excreted (pissed away).
Iodine 131:
Iodine 131 is a radioactive isotope that can result from fission of Uranium. About three percent of the U235 fissions result in Iodine 131. It has an 8 day half life; in other words for a given sample of Iodine 131 the amount present decreases by half every 8 days. If there is a release of fission products in a reactor accident such as those in Japan some Iodine 131 will be released. This can accumulate in the thyroid glands by displacing “normal” iodine and result in a radioactive thyroid gland.
Iodine tablets:
Iodine tablets are Potassium Iodide. They can be provided to people in the immediate vicinity of a reactor accident resulting in fission product release. They provide an excess of “normal” iodine to displace Iodine 131 in the body; thus reducing Iodine 131 concentration in the thyroid glands.
Reactor accidents in Japan:
The reactors automatically scrammed on the initial earthquakes. This resulted in very few fission events afterward because the reactors became subcrititcal. The fuel element failures and containment failures resulted in release of fission products to the atmosphere.
Effects in the United States:
Due to the 8 day half life of Iodine 131 and the dispersal of the fission products from the Japanese accidents it is highly unlikely that significant quantities of Iodine 131 will reach people in the United States. “Precautionary” consumption of iodine tablets in the belief that they will result in “radiation protection” is counterproductive. There may be adverse health effects from excessive potassium and iodine consumption. I am not qualified to further elaborate on these possible effects.
Conclusion:
Don't gulp iodine tablets in the belief that they are “anti radiation tablets.”