Kyodo: Plutonium detected at multiple locations outside 20km zone — Up to 35 Bq/kg of Pu-241

Published: March 8th, 2012 at 12:04 pm ET


March 8 Kyodo report in Japanese-only summarized by Fukushima Diary:

Mr. Zun from National Institute of Radiological Sciences measured Plutonium 241 […]

It was in the dead leaves of Namiemachi [26km] and Iidatemura [32km] taken in April and May, and the soil from J-village.

Plutonium 239 (half life time 24,000 years) and plutonium 240 (6,600 years) were also measured.


  • Dead leaves of Namiemachi : 34.8 Bq/Kg
  • Dead leaves of Iidatemura : 20.2 Bq/Kg
  • J-village : 4.52 Bq/Kg


Read the report here

Published: March 8th, 2012 at 12:04 pm ET


Related Posts

  1. “Deplorable”: Plutonium detected at 5 locations — “Unknown which reactor plutonium came from” March 28, 2011
  2. Kyodo: Gov’t says plutonium appears to be from meltdowns — Found at 6 locations — 45 km from plant in Iitate September 30, 2011
  3. Group with SAM 940 isotope identifier detected high levels of Plutonium-239 near Iwaki a month after quake — 50km south of Fukushima Daiichi — Found at multiple locations (MAP & VIDEO) March 22, 2012
  4. Gov’t: Highest plutonium concentration found almost 20km away from Fukushima plant March 14, 2012
  5. First Time: Gov’t admits Plutonium-238 detected in locations far from Fukushima plant September 30, 2011

23 comments to Kyodo: Plutonium detected at multiple locations outside 20km zone — Up to 35 Bq/kg of Pu-241

  • cnsrndctzn cnsrndctzn

    I would love to see what the plutonium detection is from around the rest of the northern hemisphere.


      Safe to PRESUME similar if not actually higher than levels indicated here. I know a person with a scintillation device, but they're pretty "tight-lipped" about any "findings"… This person is located on the 45* line halfway(approx) around the globe from Japan.
      I believe said device is used to detect ALPHA PARTICLES.
      I believe said device detects PLUTONIUM.
      Anyone here have access to a similar device?

  • InfoPest InfoPest

    Fukushima Diary is saying that the winds will be blowing South for a couple of days in Japan. I believe the tree pollen numbers are getting high right about now. Tokyo might have a big shock when that pollen arrives.

  • AGreenRoad AGreenRoad

    I wonder what these readings translate into as far as weight of plutonium per square meter?

    It sounds like an awful lot of nano particles per square meter to me…

    How Dangerous Is 400-600 Pounds Of Plutonium Nano Particle Dust Liberated By Fukushima? Via A Green Road Blog

    • lam335 lam335

      Thanks for this link. I just want to add one factoid.

      re: "The problem with plutonium studies is that they did not seem to focus on ANY children. "

      Actually, back when the Manhattan project did its infamous plutonium injection experiments, one of the victims they injected, without informed consent on the part of himself or his parents, was a four-year-old boy.

      That says a great deal about the morality and personal character of the men who were involved in that project.

      • lam335 lam335

        Or perhaps more aptly: … the [im]morality and [lack of] personal character of the men involved in the Manhattan project.

  • TheBigPicture TheBigPicture

    Nuke plants must be shut down, and will. But we need to get on it, pronto.

  • Kevin Kevin


    A paper out today in the journal Scientific Reports shows evidence that radioactive plutonium spread tens of kilometres from the Fukushima Daiichi nuclear plant. The new work could lead people to believe that there is a health risk, but that is not the case.

    Plutonium is a radioactive element that is made inside nuclear reactors. Unlike some of the other contaminants to come from Fukushima, it is not volatile, and it is much harder for plutonium to escape from a nuclear reactor during a meltdown. That doesn’t mean it can’t happen: when Chernobyl’s Unit 4 reactor exploded in 1984, it released a large quantity of plutonium into the surrounding environment.

    Plutonium can be dangerous. When it decays, it usually releases heavy particles such as electrons and helium nuclei. These particles aren’t particularly dangerous outside the body, but if plutonium is ingested they can cause genetic damage.

    The new paper shows that minute quantities of plutonium from Fukushima have spread far from the plant. In samples taken to the northwest and in the J-Village, where workers live, the authors found trace amounts of plutonium in the surface soil (see map). Looking at the ratio of plutonium-241 to plutonium-239, they were able to conclude that the plutonium came from Fukushima rather than other sources, such as old nuclear-weapon tests.

    The additional exposure from inhaling this loose plutonium at the S2 site is around 0.5 millisieverts (mSv) over 50 years.

    This dose — 0.5 mSv over half a century — is five times higher than the government’s current estimate for plutonium exposure from the accident, but it doesn’t mean there’s a health risk. Over the same period, the average person on Earth would receive 120 mSv from natural sources of radiation. Even for those who worry about low-dose radiation, it’s safe to say that this additional plutonium exposure won’t have an impact.

    • Kevin Kevin

      I thought I wuold follow up this post with the caveat that this language is from the Nature magazine blog, and not my own. I would not make such ridiculous statments like " might lead people to believe it is a health risk, but that is not the case"

      I leave that stuff to the pros.

      Personally I am of the mind that plutonium released from the disaster presents a health risk, of course I am not a doctor nor do I publish in the scientific journal.

      • aigeezer aigeezer

        I'd never come across spin using the "half century" gimmick before. We should brace ourselves for Sieverts/millenium next, I guess, or planets/epoch.

        • Misitu

          The loose logic invoked here is similar to what I have noted in shill posts in public websites (of newspapers, for example). The final sentence, and the second clause therein, are good models of this construction.

          The devil is of course in the detail, which is missing in such posts: in this case, (a) internal versus external, and (b) concentration by area / by biology.

          • Kevin Kevin

            As disturbing as it is to see "respected" journals publish such stuff, the plutonium cartoon really hits me where it hurts. I cannot believe to what lengths this industry will go to propagandize children. It just urks me.

    • Bobby1

      So, supposedly, breathing plutonium particles is a comparable thing to being exposed to natural background radiation.

      So much for the credibility of one of the world's most prestigious scientific journals.

      • Kevin Kevin

        Apparently, "no health risk" ala the big minds at the scientific journal. But the cartoon is the kicker! Clearly aimed right at children, the most at risk target audience.

  • Kevin Kevin

    But just to be sure lets give pluto-kun the final word.

    Must see:

    Where this reassuring quote can also be found:

    "Traces of plutonium are not uncommon in soil because they were deposited worldwide during the atmospheric nuclear testing era. However, the isotopic composition of the plutonium found at Fukushima Daiichi suggests the material came from the reactor site, according to TEPCO officials. Still, the quantity of plutonium found does not exceed background levels tracked by Japan’s Ministry of Education, Culture, Sports, Science and Technology over the past 30 years."

  • yeah and thats why in each and every film about Pu in the last decades it is handled by robotic arms (which are themselves handled by funny costumed guys) behind half a meter security-glass in steal-sealed chambers.