Radiation, Food and Iodine

Its interesting to see how the the insidious spread of radiation in Japan food supply is so quickly dismissed when news of the invasion of Libya takes the front page.

I think the idea is that "the masses" - that is us - need to be focused elsewhere so that when it comes time to upgrade our "clean, safe" nuclear reactors we will have forgotten all about Japan and its problems.

Currently Japan is experiencing an increase of Iodine-131 in its food supply.

Iodine-131 is a direct product of fission - about 3% of the byproducts of fission in uranium and plutonium.  Though its half life is only eight days it is still very dangerous.

Iodine-131 decays through the emission of beta radiation (described in this post).  Since Iodine is a critical nutrient required for the functioning of the human body and because most (maybe 94%) people on the planet are Iodine deficient radioactive Iodine is readily absorbed by the body.  The radioactive Iodine travels directly to your thyroid where its beta radiation destroys this important gland leaving you without a thyroid.

This is why you see people rushing out to buy "Iodine pills" in places like California.

Now there are some interesting issues related to this.  First of all the daily recommended dosage of Iodine for humans is 150 mcg (that's micro grams).  As I have written in the link above I believe this is far to low - people should consume more like 2 mg (milligrams) per day (or about ten times as much).   The "Iodine pills" sold to prevent radioactive Iodine damage to your thyroid have a dosage of between 65 mg and 120 mg (that's from Googling around for "iodine pills dosage radiation").  About 30 times a safe daily dosage.

Now the Japanese are one of the few people who are generally not Iodine deficient.  This is because of their diet.  They eat a lot of seaweed and seafood-based products. Since seawater has a high concentration of natural iodine the life in it does as well - and since this is the bulk of what Japan consumes in its diet they generally are not iodine deficient.

So actually they are probably less likely than most other cultures to be damaged by Iodine-131.

On the other hand, those that are consuming the "Iodine pills" in fear of the Japanese radiation are very likely getting way to much Iodine - which is also dangerous.

The problem with all of this is that once the radioactive isotopes like Cesium-137 and Iodine-131 are in the environment they are hard to detect without special equipment and/or labs.  So that means that average joe at home would likely never know if they were consuming radiation-tainted food.  Radiation is also not routinely checked in food - both in Japan and in the USA.  So unless a producer or government agency specifically works to detect contamination it will likely never be discovered.

All this leads to yet another reason why nuclear power is bad:  radiation contamination is not something that is easy, cheap or quick to detect.  So if and when it occurs no one will likely know.

Secondly, radiation in food accumulates in your body - that is if its part of an element like Iodine which is required for proper bodily function and health your body will absorb and retain it.  In doing so the radioactive decay of that element will be what does damage to you health.

Sadly as I watched coverage of the crisis in Japan no one bothered to explain any of this to the public.  While the underlying physics are complicated and will make most people's eyes roll back into their heads the common sense aspects of it are not hard to grasp.

But I suppose factual explanations don't sell news.