Some Iodine Information

[tabatha]

Where do iodine-129 and iodine-131 come from?
Both iodine-129 and iodine-131 are produced by the fission of uranium atoms during operation of nuclear reactors and by plutonium (or uranium) in the detonation of nuclear weapons.


What are the properties of iodine-129 and iodine-131?
Radioactive iodines have the same physical properties as stable iodine. However, radioactive iodines decay with time

Iodine reacts easily with other chemicals, and isotopes of iodine are found as compounds rather than as a pure elemental nuclide. Thus, iodine-129 and -131 found in nuclear facilities and waste treatment plants quickly form compounds with the mixture of chemicals present. However, iodine released to the environment from nuclear power plants is usually a gas.

Iodine-129 has a half-life of 15.7 million years; iodine-131 has a half-life of about 8 days. Both emit beta particles upon radioactive decay.


What are iodine radioisotopes used for?
Iodines are among the most widely used radionuclides, mostly in the medical field. Because of its short half-life and useful beta emission, iodine-131 is used extensively in nuclear medicine.

* Its tendency to collect in the thyroid gland makes iodine especially useful for diagnosing and treating thyroid problems. Iodine-123 is widely used in medical imaging, and I-124 is useful in immunotherapy.

* Iodine's chemical properties make it easy to attach to molecules for imaging studies. It is useful in tracking the metabolism of drugs or compounds, or for viewing structural defects in various organs, such as the heart.

* A less common isotope, iodine-125, is sometimes used to treat cancerous tissue.

Iodine-129 has little practical use, but may be used to check some radioactivity counters in diagnostic testing laboratories.


http://www.epa.gov/radiation/radionuclides/iodine.html

[davepdx]

1. The info on I-131 is not quite complete

In addition to beta decay there is also a gamma ray emission of 364 keV.

[upi402]

2. Do you think the west coast is safe? n/t

[davepdx]

4. There isn't any data upon which to draw any conclusions

You asked a question and I will reply but please understand that I am not technically qualified to answer as I am not a Radiation Health Physicist. I was a Nuclear Medicine Technologist for over 25 years and I worked with Iodine-131, Cesium-137, and Strontium-90 among many other radioisotopes during my career. My overall perspective on the issue of nuclear power plants: I am anti-nuclear power, if only for the radioactive waste disposal issue. Until I see some hard data on how much and what type of radioactive material was spilled into the environment and what any measurements are that are taken here on the west coast, I'm not going to be significantly worried much less run around doing the chicken little bit like I see some people doing. We don't have any hard evidence from which to draw any conclusions, much less to predict. I am very much worried for those people living in the immediate area of the reactors though.

In post number 3 flamingdem indicates the method that I would use if any significant amount of Iodine-131 is found. Iodine-131 has a half-life of just over 8 days. A rule of thumb (you can do the math if you want) is that if you start with a specific amount of radioactivity and wait 7 half-lives you will have just less than 1% of the amount you started with. 7 X 8 = 56 days. I expect that *if* any trace amounts of Iodine-131 is detected here it will be in trace amounts (due to dilution factors). You can "wait out" and let radioactive decay occur by not eating or drinking those products produced, like milk, by animals that eat contaminated grass.

Cesium-137 and Strontium-90 are much more of a concern to my mind. Cesium-137 has a 30 year half-life and Strontium-90 has a 28.8 year half-life they won't be decaying significantly for 100's of years. So I am concerned about the potential of contamination with Cesium-137 and Strontium-90 but at this point I am not going to work myself up because there is no data upon which to even start to draw any conclusions. I'm expecting that if these radioactive particles are detected that they will be widely dispersed and will be in very, very small amounts due the distance we are from the source and the considerable dilution in air.

There may be other isotopes that are released into the environment and I don't feel confident to comment one way or the other on these as I did not work with those isotopes during my career. I have an opinion certainly but I'd look to others that have worked with them (say nuclear engineers or radiation health physicists) to draw any conclusions.

[flamingdem]

3. Thanks, I'm trying to understand which isotopes will be in the fallout

and if iodine-123 has a half life of 8 days, then I can see avoiding milk products for several months considering the production cycle. Depending of course on when the plant stops oozing.

Now if it explodes I'm very concerned that we're dealing with different isoltops; strontium, plutonium, others - insights appreciated.

[seabeyond]

5. for what it is worth, saying supply is short and people in u.s. buying. needs to go to japan

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=385x564127

maddow had a show i just listened to, if anyone is interested