How High Are Radiation Levels in Japan? → Washingtons Blog
How High Are Radiation Levels in Japan? - Washingtons Blog

Tuesday, April 5, 2011

How High Are Radiation Levels in Japan?

How high is the radiation from Japan's leaking Fukushima Daiichi complex?

As I noted on March 29th, radioactive cesium from Japan already rivals Chernobyl.

Greenpeace has measured very high levels of radiation some 40 killometers from Fukushima:

The Japan Times reports that there are extremely high levels of radiation in and around the nuclear plants:
Radioactive iodine-131 readings taken from seawater near the water intake of the Fukushima No. 1 nuclear plant's No. 2 reactor reached 7.5 million times the legal limit, Tokyo Electric Power Co. admitted Tuesday.

The sample that yielded the high reading was taken Saturday, before Tepco announced Monday it would start releasing radioactive water into the sea [see this for background], and experts fear the contamination may spread well beyond Japan's shores to affect seafood overseas.

The unstoppable radioactive discharge into the Pacific has prompted experts to sound the alarm, as cesium, which has a much longer half-life than iodine, is expected to concentrate in the upper food chain.

According to Tepco, some 300,000 becquerels per sq. centimeter of radioactive iodine-131 was detected Saturday, while the amount of cesium-134 was 2 million times the maximum amount permitted and cesium-137 was 1.3 million times the amount allowable.


The level of radioactive iodine in the polluted water inside reactor 2's cracked storage pit had an even higher concentration. A water sample Saturday had 5.2 million becquerels of iodine per sq. centimeter, or 130 million times the maximum amount allowable, and water leaking from the crack had a reading of 5.4 million becquerels, Tepco said.


Masayoshi Yamamoto, a professor of radiology at Kanazawa University, said the high level of cesium is the more worrisome find.

"By the time radioactive iodine is taken in by plankton, which is eaten by smaller fish and then by bigger fish, it will be diluted by the sea and the amount will decrease because of its eight-day half-life," Yamamoto said. "But cesium is a bigger problem."

The half-life of cesium-137 is 30 years, while that for cesium-134 is two years. The longer half-life means it will probably concentrate in the upper food chain.

Yamamoto said such radioactive materials are likely to be detected in fish and other marine products in Japan and other nations in the short and long run, posing a serious threat to the seafood industry in other nations as well.

Indeed, high levels of radioactive cesium above the legal limits have already been detected in small fish called "sand lances" off the coast of Ibaraki, almost 100 miles south of Fukushima.

And NHK news points out that radiation levels are so high in some locations that they are literally "immeasurable":

A radiation monitor at the troubled Fukushima Daiichi nuclear power plant says workers there are exposed to immeasurable levels of radiation.

The monitor told NHK that no one can enter the plant's No. 1 through 3 reactor buildings because radiation levels are so high that monitoring devices have been rendered useless. He said even levels outside the buildings exceed 100 millisieverts in some places.


  1. What is taking so damn long for them to bury the fucking plant in cement like they did in Chernobyl? Its been three weeks and they cant even find out where the leaks are coming from? Why are they still trying to work in the plant and contain it? Bury the whole thing in massive amounts of cement and end the story already. The more time this goes on the more radiation is released.. this is so fucking ridiculous! i am so mad. Why have nuclear plants in high risk earthquake zones? So fucking stupid!

  2. You can't 'just bury the fucking plant in cement'; it's too hot. The Chernobyl accident was entirely different. Jeez...

  3. we would far better off without cars, elektricity, city smog,gmo food, nuclear plants

  4. Dummy, Chernobyl was and still is cooled by what and how? Do a search. It was as hot as fuckyoushima, but these were Russians and not these stupid japaneeeese.

  5. Chernobyl blew up, and didn't have a containment the material was already separated and reaction stopped at the point of the explosion. All that was left to do was contain the material in the sarcophagus (which is currently falling apart and needs billions in repairs BTW)

    I think they are still trying because theoretically, if they managed to get the fuel rods cool enough (I think that takes like years) they could actually remove them and shut down the plant properly.

    What they are gonna do with the water is anybody's guess.

    It is kinda crazy though that they can't even identify leaks and other things that are going on in there...ever heard of a CCTV camera guys?

  6. "It will probably concentrate in the upper food chain." -- Thats us.

  7. NHK says the leaks to the sea have stopped. (Also, I saw a great couple of sections on NHK Newsline last evening, which I blogged on.)

    "What will they do with the water?"

    They will build a filtering system/plant.
    It would be quite pleasant to have robots that could work inside the buildings I bet.

    btw, measurements like x millions times legal limit isn't meaningful. In contrast, an actual number, that can be compared to a chart or graphic or table (there are several on the internet) will allow people to actually calculate meaningful numbers. The one meaningful datum given here is the 100mSv (presumably per hour). At that rate, a fresh worker would have only about 2 hours in that kind of intensity, and then it's outta there.

    Hopefully they have their water injection systems set up well enough already. If not....

  8. A CCTV Camera would be useless near to such intense radiation, the electronics will malfunction and fry due to off the scale Gamma irradiation, the CCD will also get overloaded and fried by Alpha and Beta particles.

    If they want to look in there remotely, they need a very long armoured fibre optic cable from a TV Camera to a Radiation resistant lens, i.e. a huge endoscope!

  9. I'm sure the levels are pretty high. This radiation is now showing up in the rain water falling into the United States and Canada at levels 3300% of normal. This can be devastating to say the least to all humankind! The effects of radiation sickness and poisoning include cancer, genetic and reproductive damage, hormonal damage, and thyroid blockage (that's why they want you to take potassium iodine, another dangerous toxin) but I wouldn't. There are much safer substances like Zeolite.

    A couple good articles on radiation sickness protection that shows what you need do to test radiation levels, treat water, and what to take internally to not get sick:

    Water Purification

    Radiation Sickness

  10. One thing to do is go vegetarian. Factory farming produces more greenhouse gasses than all divisions of transportation combined. Another thing is that the lower you eat on the food chain the less concentrated toxins you get of all types.


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