# Finding Potassium Iodide tablets **URL:** \ **Category:** Cecil's Columns/Staff Reports\ **Created:** [August 13, 2003, 7:36pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990 "2003-08-13T19:36:32Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [August 13, 2003, 7:36pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/1 "2003-08-13T19:36:32Z")
In the classic SD column at [http://www.straightdope.com/classics/a1\_239a.html](http://www.straightdope.com/classics/a1_239a.html), unca Cece says: > [@](#): > > In a survivalist magazine some years ago I saw an ad offering a “doublepack” of [potassium iodide] (supposedly enough for two adults) for $10 plus $2 shipping. At the time $12 struck me as a little steep; if I were you I’d shop around. Yes, from my experience, survivalist magazines and “preparedness” stores do tend to overcharge. So, I waltzed on down to my local General Nutrition Center (GNC) store, and … discovered that GNC doesn’t carry potassium iodide. I wondered why, until I realized who the target demographic was for GNC stores in the first place. GNC primarily sells vitamin and mineral supplements. Their primary customers are the same types of people that frequent health food stores. Of those people who buy health food, the overwhelming majority are _left-of-center_ politically. However, potassium iodide is no ordinary vitamin or mineral supplement. It’s supposed to allow you to better survive the radioactive fallout from a nuclear strike. Most of the people who are interested in potassium iodide are survivalists – and the overwhelming majority of survivalists are _right-of-center_ politically. Since GNC’s main product lines appeal to people on the other side of the political spectrum from the usual survivalists, they probably get very few survivalists in their stores. Therefore, it would not be profitable for them to stock survivalist items, therefore, they don’t carry potassium iodide. Q.E.D… ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [August 13, 2003, 7:49pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/2 "2003-08-13T19:49:53Z")
One more time on that URL: [Do radiation-nullifying pills actually work?](http://www.straightdope.com/classics/a1_239a.html) ---
**Author:** ![AskNott](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/asknott/32/5790_2.png) [@AskNott](https://boards.straightdope.com/u/AskNott)\ **Post date:** [August 13, 2003, 9:56pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/3 "2003-08-13T21:56:09Z")
Couldn’t you load up on iodine by simply using a little more iodized salt on your food than usual? I’m assuming that it wouldn’t be needed until a nuclear alert was issued. Yesterday, I bought a 26 ounce box of iodized salt for $.37. ---
**Author:** ![momomoto](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@momomoto](https://boards.straightdope.com/u/momomoto)\ **Post date:** [August 13, 2003, 10:23pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/4 "2003-08-13T22:23:13Z")
There probably isn’t enough iodine in a box of salt to make an appreciable difference. A teaspoon of salt (15 mL, or about 33 grams) contains 300 micrograms of potassium iodide, or roughly .5% iodine w/w. The amount of salt you’d need to eat in order to get an equivalent dose that a single KI tablet would provide is ridiculously large, not to mention unhealthy and not much fun. You’d have to take the salt within a relatively short time, I think, in order to make sure that you do overload your thyroid. ---
**Author:** ![momomoto](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@momomoto](https://boards.straightdope.com/u/momomoto)\ **Post date:** [August 13, 2003, 10:34pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/5 "2003-08-13T22:34:43Z")
Is there any chance, Cecil (or the powers that be), that you could edit the column ([http://www.straightdope.com/classics/a1\_239a.html](http://www.straightdope.com/classics/a1_239a.html)) so it refers to KI instead of PI? PI would be phosphorous iodide, dontcha know. ---
**Author:** ![tracer](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tracer/32/20578_2.png) [@tracer](https://boards.straightdope.com/u/tracer)\ **Post date:** [August 13, 2003, 11:27pm UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/6 "2003-08-13T23:27:34Z")
Considering the article was written in 1984, any edits at this point are highly dubious. Besides, “PI” could just be an English-language abbreviation for Potassium Iodide, not its chemical formula. Plus, it has the bonus of also being the abbreviation for “Private Investigator”, especially when preceded by a “Magnum”. ---
**Author:** ![I\_am\_not\_a\_jerk](https://avatars.discourse-cdn.com/v4/letter/i/a3d4f5/32.png) [@I\_am\_not\_a\_jerk](https://boards.straightdope.com/u/I_am_not_a_jerk)\ **Post date:** [August 14, 2003, 2:02am UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/7 "2003-08-14T02:02:10Z")
Just interested in the pricing of KI. Quick googling found the following, for $16.95: [http://www.campingsurvival.com/anpotiodreft.html](http://www.campingsurvival.com/anpotiodreft.html) \ Now you have a smart choice - Anti-Rad™ KI. There are 200 tablets of KI - 65mg per tablet. This is a 100 day supply for an adult, and a 50 day supply for 2 adults. \ Now, you could probably argue that 8-9 cents per KI tablet is still steep – I don’t want to do any further googling to find lowest-priced KI – but I’m thinking you really won’t care about $20 if you’re in a 50-day nuclear emergency. 🙂 or is it ☹ ---
**Author:** ![Roches](https://avatars.discourse-cdn.com/v4/letter/r/bc8723/32.png) [@Roches](https://boards.straightdope.com/u/Roches)\ **Post date:** [August 14, 2003, 11:37am UTC](https://boards.straightdope.com/t/finding-potassium-iodide-tablets/194990/8 "2003-08-14T11:37:41Z")
well, i finally joined this message board just to talk about this PI thing. i should be studying for an organometallic chemistry exam, but the irony in this is too good to miss. first, the article isn’t the same as the one published in 1984 – otherwise it wouldn’t talk about ‘vestiges of the Cold War’ or India conducting nuclear testing. so maybe there’s still hope. the possibility that it was KI in the original and has been changed to PI is unthinkable and impossible. i’m sure there’s a good explanation for the PI _issue_. i’d like to think it’s this: PI must mean potassium iodide, in context, because PI cannot be phosphorus iodide. phosphorus has 2 common positive oxidation states: (III) and (V). only P(III) forms a simple iodide, PI3, phosphor **ous** iodide (or triiodophosphorus(III) or phosphorous(III) iodide or whatever). PI5 doesn’t exist (5 iodines are too large to fit around phosphorus), but there’s a dimer, P2I4 (which contains P(II), but there’s not many P(II) compounds) so, PI not being a stable compound, ‘PI’ in the article must mean potassium iodide. i will assume that details regarding the role of iodine in the biosynthesis of thyroxine and triiodothyronine were left out because everyone reading the article either doesn’t care or already knows (it was high school for me, so i’ve forgotten what they do, but ‘that’s not my field’ =)) incidentally, the iodine in KI is 127I, the only naturally occuring isotope. the radioisotopes range from 120I to 135I and have half-lives ranging from 25 minutes to 1.7 x 107 years. most of the half-lives are short (maybe 5-10 days); the short half-life is one reason why radioactive iodine is dangerous (another is probably its limited role in the body). if you want to know all the radioisotopes of iodine (and you probably do =)): [http://www.webelements.com/webelements/elements/text/I/radio.html](http://www.webelements.com/webelements/elements/text/I/radio.html) i’m not sure what the composition of fallout is, but as far as I know KI is the only way to protect against even part of it. radioactive iodine is probably one of the more dangerous radioisotopes in fallout – assuming that most of the radioactive material is rather heavy, i’d think iodine is the major component of fallout that also features in human metabolism. this means, unfortunately, that the market in iridium(III) chloride tablets for protection against 188Ir (and inducing heavy-metal poisoning…) is, uh, limited.