CNN reports that water pouring into the Pacific Ocean from the “stricken” – I personally think malignant is a better word – Fukushima nuclear power plant is radioactive 7.5 million times (that’s a seven and a five, followed by five zeros) times the legal limit. Obviously, the law is really asleep at the switch to let that happen.
No, belay that; the law is working. Now the radiation in the water is down to only five millions times the legal limit. Truly, a victory for the rule of law.
Since radioactive iodine has now been detected in fish caught off Japan, the Japanese government has imposed a limit on the radiation in fish and set the rule of law to work immediately.
Regrettably, of course, sometimes the laws of physics trump the rule of law.
Meanwhile, officials in the U.S. tell us not to worry; this isn’t a health risk, even for the fish!
John Till, president of the South Carolina-based Risk Assessment Corp., said he does not expect to see any permanent effects on marine life, even close to the plant. However, he added that officials should monitor radiation levels closely -- in the ocean as well as in seafood that reaches restaurants and markets.
Personally, I don’t favor getting health information from insurance executives.
Now this is just a hunch, but I wouldn’t be surprised to see radiation – in safe amounts, we will be told – start showing up in Pacific salmon as they start their spawning runs in Alaska and the Pacific Northwest, if not this summer, then next. As predator fish with a large Pacific range, they’ll eat bait fish that have been exposed to the radioactive iodine in the water; radioactive isotope of iodine are associated with thyroid cancer. The iodine (or cesium) will begin to accumulate in the larger predator species, just as mercury does. Over time, the radioactivity decays, but in one isotope of radioactive iodine, 129, a product of nuclear fission, the half life is 15.7 million years.
The fish above is from a Simpson’s episode.
Update: Here’s a little more about radioactivity accumulating in fish:
With a radioactive half-life of 30 years, cesium can build up in the meat of marine predators as they eat smaller animals, said Karen Gaines, chairwoman of the biology department at the University of Eastern Illinois in Charleston.
“If they’re going to restart fisheries and make people feel comfortable, they’ll need real-time monitoring of the catch,” said Gaines, who studies radioactive cesium in animals at the Savannah River Site in South Carolina, which made plutonium for U.S. nuclear weapons. (The sushi graphic in this update is from Avidor.)
Further update: Here is a challenging but very good post at A Tiny Revolution about why the simple linear dose model for radiation (“it’s much less than a chest x-ray!”) is of dubious validity:
I am actually sympathetic to the dose assumption. For one thing, I like the physics. If you’re trained in the field, then it’s sensible to think in terms of mass attenuation coefficients, linear energy transfer, cascades, and such things. But you should note that calculation of quantities such as these refer to model biological systems which are inanimate. This sounds complicated, but all it means is that dose calculations treat living beings as though they were not alive.