Friday, March 25, 2011

Japan Expands Exclusion Zone; Reactor 3 Possibly Leaking

Not good sign at all.

Japan has widened the exclusion zone around the Fukushima Daiichii power plant, by “recommending” residents in a 20km-30km band around the plant leave and telling them to prepare for a possible mandatory evacuation.
Meanwhile, Japanese authorities are now saying a  likely breach in the containment vessel of reactor 3 may have occurred. This is extremely serious, since reactor 3, unlike the other reactors can spew out radioactive plutonium.
Japan's Health Ministry recently raised the maximum level of exposure for a person working at the site  to  from 100 millisieverts to 250 millisieverts per year. Exposure to 100 millisieverts are said to "clearly be linked to increased risk of cancer" at 400 millisieverts of exposure, with in a short period of the exposure.symptoms of radiation poisoning occur. 


  1. "reactor 3, unlike the other reactors can spew out radioactive plutonium."

    BZZZZT! Wrong. All irradiated reactor fuel contains plutonium. Any time fuel is damaged there is danger of releasing fission products, which includes plutonium.


    Plutonium is nowhere near the bugaboo toxin the is commonly claimed. See

    "Plutonium is more dangerous when inhaled than when ingested. The risk of lung cancer increases once the total dose equivalent of inhaled radiation exceeds 400 mSv. The U.S. Department of Energy estimates that the lifetime cancer risk for inhaling 5,000 plutonium particles, each about 3 microns wide, to be 1% over the background U.S. average."

    But that may be too pessimistic, from the same wiki entry:

    Several populations of people who have been exposed to plutonium dust (e.g. people living down-wind of Nevada test sites, Hiroshima survivors, nuclear facility workers, and "terminally ill" patients injected with Pu in 1945–46 to study Pu metabolism) have been carefully followed and analyzed.

    "These studies generally do not show especially high plutonium toxicity or plutonium-induced cancer results. "There were about 25 workers from Los Alamos National Laboratory who inhaled a considerable amount of plutonium dust during the 1940's; according to the hot-particle theory, each of them has a 99.5% chance of being dead from lung cancer by now, but there has not been a single lung cancer among them.""

  2. why "radioactive plutonium" should be a problem?
    sorry, but these posts seem to have only the purpose of propagating misinformation and superstition.
    get your facts right, please.

  3. Radioactive plutonium is a problem because of its long half life. Radioactive iodine, which is currently spewing from the other reactors, has a half life of 8 days. That's why radioacive counts in Tokyo dropped so fast, after one dosing of radioactive iodine. The half life of radioactive plutoniuom is measured in years. Once it gets out it is going to be around for a very long time.

    Or do you think the emergency workers at Fukushima have been making an error in focusing on reactor 3, which can spew the radioactive plutonium in high doses?

  4. Your misunderstanding persists. Iodine-131 is dangerous precisely because it has such a short half life and is biologically active. Once adsorbed by the body it tends to end up in the thyroid, where in just 8 days half of it has decayed and irradiated the critical gland. In another 8 days 3/4 has delivered its dose.

    Plutonium is much less biologically active. As the wikipedia entry (which you either did not read or do not understand) noted, plutonium is dangerous when inhaled, because that is the way for it to get into the body - dust can lodge in the lungs.

    Plutonium-239, the ingredient of interest in MOX fuel that is present in ALL irradiated uranium fuel, has a half life of 24,000 years. That means that an equivalent amount of radioactive plutonium delivers its does of radiation 8,765,760 times SLOWER than Iodine-131, and it doesn't deliver the dose directly to a sensitive endocrine gland like the thyroid.

    I don't accuse the workers, who have infinitely more knowledge than you or I about the actual situation, of making an error. I also do not accept that they are "focusing on reactor 3," as they have already brought reactors 5 and 6 to cold shutdown status, and have spent a great deal of time and risk working with reactors 1, 2, and 4.

    Your bald assertion that "reactor 3, which can spew the radioactive plutonium in high doses" is unsupported and false. IF the containment in any reactor is breached, a leak of plutonium and many other fission products is possible. ALL reactors that have been operated have plutonium. The risk of "spewing" radiation is almost certainly greater in the spent fuel pools, because unlike the reactor cores, they are not encased in 8+ inches of high-strength steel. It is possible and perhaps likely that the radiation found in the turbine building of reactor 3 came from the spent fuel pool, not from the reactor core.

  5. Gee, I guess the Japanese government can change the lethality of radiation exposure simply by raising their legally proscribed limits! In Japan, at least, the Japanese government's perception is reality!

  6. @Anonymous 12:24

    You write:

    "The risk of 'spewing' radiation is almost certainly greater in the spent fuel pools, because unlike the reactor cores, they are not encased in 8+ inches of high-strength steel."

    Which is really making my point, since we know for sure that the water was out of the fuel pool in Reactor 4, but numerous reports from various sources over a week cleaarly state that the focus was on reactor 3.

    I ask why the focus on reactor3, if it is no big deal?

  7. "we know for sure that the water was out of the fuel pool in Reactor 4"

    We know no such thing. You are repeating the baseless claims of a US government bureaucrat, whose ignorance of the local situation is nearly as great as your own.

    The Japanese authorities, who happen to be on site and have a keen interest in understanding the true situation, reported that there was at least some water in SFP of reactor 4, which they saw at some risk by flying a helicopter over the building.

    Cite your reports that "the focus was on reactor 3" I've been following this event from the beginning, and the people who know what they are talking about have said no such thing. All ten reactors must be stabilized, cooled, and monitored. Six are presently in cold shutdown state. They are working on the other 4.

    The high radiation levels at reactor 3 have hampered progress. That is not the same as "focus."