Radioactive cesium not detectable in 99% of Fukushima residents: study


Radioactive cesium was too low to detect in 99 percent of 22,000 residents examined in Fukushima Prefecture and neighboring Ibaraki, according to a University of Tokyo survey.

The team, which included professor Ryugo Hayano, examined internal radiation exposure levels in the two prefectures between March and November 2012. Their findings were unveiled Wednesday in the Transactions of the Japan Academy.

The survey found that the rate of internal exposure in the residents surveyed stood at about one-hundredth of the level detected in people living in the area around the Chernobyl plant at the time of the 1986 disaster.

Levels of cesium-137 were shown to be below the detectable threshold of 300 becquerels per kilogram of body weight for 99 percent of the residents, according to the team.

For the remaining 1 percent, or 212 people, 10 becquerels were detected. Still, their annual internal exposure would total only 0.04 millisievert, far below the government-set limit of 1 millisievert per year, the team said.

Meanwhile, cesium levels equivalent to 1 millisievert of internal exposure at an annualized rate were found in four elderly people who routinely ate wild mushrooms and boars. The team confirmed that the figures dropped after these four changed their eating habits.

Just as with the Chernobyl crisis, soil, particularly around Fukushima, was heavily contaminated with radioactive substances following the March 2011 nuclear meltdowns at the Fukushima No. 1 power plant.

The low cesium readings were attributed to the quality of the soil in the areas surveyed, which prevented food crops from absorbing radioactive materials, the conduction of radiation checks for food and the attention local residents are paying to the produce they consume, according to Hayano.

But the team, which used a whole body counter to examine the residents, concluded that checks on internal exposure and food inspections need to be continued. The study was conducted jointly with a hospital in Fukushima Prefecture.

  • thedudeabidez

    Given the gakubatsu (old-boy) clique of Todai grads that includes TEPCO management, LDP members, METI bureaucrats, Keidanren leadership, academic commentators in the media who regularly downplay the nuclear issues, and let’s not forget the toothless Nulcear Safety Commission itself, well, it’s best to take any report emerging from Tokyo University as suspect until proven otherwise. TEPCO’s own figures report 760,000 tetrabecquerels of Cesium-137 discharged into the atmosphere, more than quadruple the amount released by Chernobyl. How this translates into 1/100th the exposure of Chernobyl-area populations is not explained by this article.

    Also, Mr. Hayano is not an expert on nuclear power, nor is he a medical doctor— his specialty is experimental nuclear physics.

    Furthermore, the hospital in Fukushima that participated in the study was not named, but there are many, many reports from Fukushima residents suffering from sudden and unexplained symptoms who go to the hospital and from the outset, the doctors refuse to even discuss the idea that they might be radiation-related. They may or may not be, but the refusal to even consider the issue given the known contamination is shocking. Twitter is full of such stories. It would seem a conclusion had already been reached and now we are seeing “data” manufactured to support it.

    • Michael Radcliffe

      Hey, why do university studies at all when we have twitter, right?

    • Masa Chekov

      It could be the largest conspiracy ever – the Japanese government, titans of industry, hospitals, officials at all levels, all in collusion, for what reason who knows – or Twitter could be wrong.

      I’ll vote on Twitter being wrong, thank you. Not to mention mainstream scientific thought agreeing broadly with the conclusions of this report.

      I think some of you are hoping for a bunch of misery just so you’ll be right.

      • thedudeabidez

        How do you suppose individuals denied the health examinations they request are supposed to make that fact known? Throw a press conference? Right, I am sure the kisha clubs will be right on that one. And beyond the sarcasm, try addressing the issue at hand: how does quadruple the C-137 released wind up with 1/100th the exposure, according to this report?

      • thedudeabidez

        For the record, I’m definitely sceptical of unsourced Twitter information as well. Yet there have been repeated stories to this effect, often with people putting their actual names to them. I think just as much scepticism is due any report published by Todai on this matter. They are part of the vast TEPCO/power utility money web as well, which is right out in the open, no need to call it a “conspiracy”.

      • Masa Chekov

        There’s no particular reason to be skeptical of a Todai-produced report. Do you have any scientific reason to doubt their claims, or are you just alleging fraud by a major academic institution because……? Do you think everyone involved in this vast conspiracy just hates their country and all its residents?

        I find it really funny that people criticize the Japanese government as toothless and incompetent except when it comes to power generation – then it becomes brutally efficient, squashing all dissent, corrupting all academics and anyone even tangentially associated with nuclear power. The most efficient conspiracy ever, apparently.

      • thedudeabidez

        Masa, the Japanese government is remarkably efficient at creating a system whereby politicans and bureaucrats do the bidding of various industries and are rewarded for it by amakudari jobs or political “donations”. This is hardly news. Don’t believe me, try the NYT:

        “It is difficult to overstate the influence of Tepco, which rivals the American defense industry in its domestic reach.Thanks to a virtual monopoly and a murky electricity pricing system, it has become one of the biggest sources of loosely regulated cash for politicians, bureaucrats and businessmen, who have repaid Tepco with unquestioning support and with the type of lax oversight that contributed to the nuclear crisis.”

        “In Japan, the web of connections between the nuclear industry and government officials is now popularly referred to as the “nuclear power village.” The expression connotes the nontransparent, collusive interests that underlie the establishment’s push to increase nuclear power … nuclear industry officials, bureaucrats, politicians and scientists — have prospered by rewarding one another with construction projects, lucrative positions, and political, financial and regulatory support. The few openly skeptical of nuclear power’s safety become village outcasts … Until recently, it had been considered political suicide to even discuss the need to reform an industry that appeared less concerned with safety than maximizing profits.”

      • Masa Chekov

        So would you be automatically opposed to any report coming from a US university that receives funding from, say, DARPA? Because that’s what you are suggesting – that a university that has any connection whatsoever to monolithic TEPCO is irredeemably tainted by said association. I don’t think anyone would rationally state that Caltech or Princeton are not to be trusted due to their association with the US Defense Department (TEPCO’s rival in political reach, according to your source) so why is Todai not to be trusted?

        And I completely fail to see the link to Todai and your sources – it is of course true that there is (or was) a too-cozy relationship with regulators and regulatees but how this translates to corruption in a major academic institution – again, this is what you are alleging – is quite unclear.

      • Ken Yasumoto-Nicolson

        Well, most of it blew over sea; milk and other foodstuffs were soon tested and banned, etc, etc, things that never happened at Chernobyl.

      • thedudeabidez

        Right, assuming that 75% of it blew out over the sea, that still leaves a Chernobyl equivalent contaminating land. I agree that the measures that were taken would mitigate exposure somewhat, but several areas that should have been evacuated were not, that much is clear. Further, re. the food testing, this was entirely voluntary — NOT mandatory — and conducted on the local level. Also, in many locales, if contaminated produce was verified, all the produce from the locality was to be banned. One can easily understand the pressures on the people doing the testing, given the effects their judgement would have on people’s livelihoods. Given the amount of food-labeling scandals in Japan in the past, one would be naive to think that this voluntary system would be entirely effective. While there were certainly many good people out there who took losses rather than distribute contaminated products, one can be sure that wasn’t everyone.

      • Masa Chekov

        Exactly what else would you rather have done? Are you seriously suggesting that a positive test for excessive radiation levels triggering a total ban of produce from that area is a bad thing? Because that’s how it reads.

        You also seem to be neglecting all the grass roots testing that has gone on by local interests. People aren’t just taking the word of authority that food is contaminant free; they have been testing it themselves.

        I am not sure why you seem to think there is a cover-up a conspiracy, that people are allowing contaminated produce to market, that major academic institutions are committing fraud that could seriously endanger people’s health. There’s no evidence whatsoever to support this, so why make these allegations?

      • Masa Chekov

        Notice the big ocean next to the plant? And the prevailing winds that tend to blow west to east? Not to mention the banning of consumption of locally produced food products (unlike in the USSR) early on.

      • Jon Miner

        Helicopters that flew radiation detection flights after the explosions reported that winds were from the south east. Areas inland to the north west received the fallout. Maps of these radiation readings are online.
        Later, rainfall carried the radiation via rivers to the bays on the southern and southwestern coasts, contaminating river beds and bay bottoms all the way. Seafood from any of those areas must be checked for contamination.

      • “How do you suppose individuals denied the health examinations they
        request are supposed to make that fact known? Throw a press conference?” Well they very well could, now couldn’t they. The press, or at least a noticeable segment of it, WOULD be right on that. The kisha club system does not control all media in Japan, far from it. As for your second question: “how does quadruple the C-137 released wind up with 1/100th the exposure?” Even assuming the “quadruple the C-137 released (as compared to Chernobyl)” is correct (which it may well be), anyone with even a bare modicum of intelligence would have noted that radioactive isotopes released from Chernobyl were released as steam, smoke and flaming chunks of reactor core and radioactive graphite directly over the surrounding countryside, in the heart of Eurasia, whereas any releases from Fukushima were in the form of steam, most of which which was carried by the prevailing winds out over the Pacific, or contaminated cooling water which likewise drained into the Pacific. This graphic is quite illuminating, although I have no doubt you would claim it is part of the “coverup”:

      • thedudeabidez

        I can’t source a date for your graphic; note that estimates (TEPCO’s own) on C-137 etc. release increased considerably well after the accident. Also, the graphic itself says the following “Cesium-137 levels approaching Chernobyl — but over a much smaller area.” I wouldn’t argue with that. But note it’s saying the C-137 level is indeed high in Fukushima.

      • thedudeabidez

        Re. the press coverage issue, who would you point to? I can think of only Shukan Kinyoubi, and their brief is pretty much covering what the rest of the media refuses to cover. Tokyo Shinbun has been aggressive on the Fukushima story too, But, as is common knowledge now, most of the MSM in Japan receives healthy advertising money from TEPCO (and why exactly does a monopoly need to advertise) which is basically a quid pro quo not to cover the nuclear sceptic side of things much or at all. Todai is of course another recipient of TEPCO funding.

    • “It would seem a conclusion had already been reached and now we are seeing “data” manufactured to support it.”

      You know, I actually agree with this statement of yours. However we would disagree on which side of the debate is manufacturing their “data”.

    • Sam Gilman

      Gio, the questions you’ve raised about this report have not been put honestly.

      You suggest that all work coming out of Tokyo University is suspect because some people who graduated from there occupy executive positions in industry and government. But you’ve been living in Japan for a long time. You *know* that Tokyo University is the top university in the country, one of the top in Asia and in the world top 50 (and by the by, ranked 14th for physics). Just like Oxbridge and the Ivy League in the UK and US, it tends to produce graduates who go on to take leading roles in government and industry. Should we suspect all graduates of Yale of being folksy warmongers just because George Bush went there? Would you prefer that the investigation had been led by someone from a much lower quality university? What kind of sense would that make?

      You also argue that Ryugo Hayano does not have the correct breadth of expertise, as if his expertise in atomic physics is the only expertise on the team. Was it beyond you to track down the other authors? It took me less than five minutes. They include a physician from Fukushima prefecture who has been involved in radiation assessments since the beginning of the crisis, as well as a radiation specialist at Fukushima Medical university and doctors from Hirata Central hospital. Your complaint that this hospital is not named is the fault of the Japan Times. Given your evident passion on the issue, is tracking down the abstract of a recently published, open access, newsworthy study really beyond you? Ironically, I found the link on Ryugo Hayano’s twitter feed.

      Your figures for the amount of caesium-137 released appears to rely on you or someone else misreading a viral and really poor Russia Today report which itself manages to misread the TEPCO figures it tries to discuss, in particular failing to understand what peta- and tera- prefixes mean, and swapping atmospheric and oceanic releases. So they get the wrong Cs-137 figures, and they are then wrong by a factor of a hundred.

      The thing is, we know that Russia Today is not a reliable source on Fukushima. (I thought everyone knew that. It gave pretend expert Arnie Gundersen loads of airtime). If you’re relying on RT, or worse, on a website that recycled it, then you’re not taking things seriously. We all know that there are people on all sides spouting rubbish about radiation. Instead of being happy to find sources that support your view, the more honest thing to do is base your views on what is reliable. Go to the source, and don’t trust journalists. They get science wrong in simple ways all the time.

      Lastly you reveal – for someone so convinced of the dangers of the releases – an astonishing ignorance of what medical symptoms radiation might produce. Radiation is not witchcraft, or a generator of all diseases. Radiation below very high levels (ie of the order of a whole Sievert that can cause acute radiation sickness) does not produce “sudden” symptoms. It results in things like cancers, often of very unusual kinds, such as thyroid cancers, that take years to develop. If you’re honestly concerned about the health impacts of Fukushima, surely you would have found time to read up on this. Google search is free.

      The thing is, when people turn up at the doctor’s, complaining of symptoms that look for all the world like stress and not a bit like cancer or any other radiogenic conditions, the doctors are quite right to say “this is not something that is caused by radiation”. They will be keen to minimize the stress because it can lead to depression, alcoholism, strains on families (with children picking up behavioral problems – all of which we can see already and has been reported on). They’re not denying anyone’s rights.

      Given that all professionally scrutinized studies by respected, mainstream scientists are concluding – as established experts from around the world have been suggesting since the beginning of the crisis – that the ultimate risk to the population from the releases is likely to be very small, where is all this destructive stress coming from? Gio, I’m afraid it’s from people like you. People who carelessly sow doubt and fear through social media without any thought of the consequences. Tweets are a better source of science than trained medical and radiological experts experts in the field? Twitter? What kind of silliness is that?

      Please, please, if you want to engage in critical analysis of sources on this issue, do it honestly. Don’t just settle on what you think you already know. That’s not honest.

      • thedudeabidez

        Sam, first things first, apparently you are right re. the C-137 figures. I didn’t get the figures from RT, but apparently the misinformation spiraled out from there. I’ll be the first to admit there’s a lot of BS on this issue spun by all sides, so thanks for pointing that out.

        Re. Todai, there’s a reason for the word “gakubatsu”, just as there is with the term “old-boy network”. It’s also known that Todai takes money from TEPCO. I am in the process of checking out the report and its authors, but yes, I would greet any Todai doc on this subject with suspicion until proven otherwise. If it turns out to be independent and objective, that will be a pleasant surprise.

        Re. the effect of low-level radiation exposure on health, cancer obviously is long-term, but you ignore the short-term symptoms entirely, I have indeed read plenty on the topic and all I know is that there is a great deal of debate over what levels are cause for immediate concern. There are plenty of reports of workers at the nuclear plants suffering debilitating illnesses — not always cancer, mind you, but severe fatigue, gastro-intestinal problems, etc. — after on-the-job exposure. (See the excellent Ch. 4 doc, Nuclear Ginza.) It is entirely possible, given the contamination in certain areas of Fukushima, especially in the first weeks after the accident, that people could have received doses worthy of concern. Now you –or the doctors –may be right, perhaps it was stress. But in such a situation, where people are reporting symptoms that are also consistent with low-level exposure, it would be prudent to run some tests on a few of these people to rule things out. Yet they were denied this option. The reasons for this are obvious: any connection with radiation and illness would have grave consequences for both the future of nuclear power in Japan, and the financial compensation that TEPCO could be responsible for. (Note the US Navy personnel suing TEPCO over medical problems they suspect are related to exposure.) Anyone who’s lived in japan long enough will surely know there won’t be a stampede of doctors eager to be the consensus-breaker setting a new and dangerous precedent.

        In terms of risk to the population, what studies are you citing? The WHO? That organization that has to run its findings by the IAEA –dedicated to the expansion of nuclear power — before being allowed to publish them?

      • Sam Gilman


        I didn’t get the figures from RT, but apparently the misinformation spiraled out from there. I’ll be the first to admit there’s a lot of BS on this issue spun by all sides, so thanks for pointing that out.

        I have to shake my head in disbelief at this. If you’re getting your information from sites that aggregate nonsense from places like Russia Today (or ENEnews or anywhere like that), then you’re just not making a serious effort to get informed. On a subject like this, the answer is not to take an average of all Internet opinions. Do that and you’d believe that vaccines were a government conspiracy to conceal aliens warming the planet to kill JFK because he had the key to free energy (but that seven-foot shape-shifting lizards got to him first). The other thing to avoid is looking for material that confirms what you believe – are you sure you’re not just doing that?)

        If you want information on science and health, go to scientists and medical researchers working in the field who have the respect of their peers. For example:

        the effect of low-level radiation exposure on health, cancer obviously is long-term, but you ignore the short-term symptoms entirely, I have indeed read plenty on the topic and all I know is that there is a great deal of debate over what levels are cause for immediate concern.

        About immediate effects of low-level radiation? I’m sorry, but no, there isn’t a great deal of debate. Not amongst publishing scientists. The only great debate over low-level radiation is long-term, and that is over whether it even has any effect at all. It’s true that there are people posing as experts who claim serious effects of low-level radiation, such as Chris Busby, Arnie Gundersen and Helen Caldicott, but they have failed to get their ideas accepted by their peers. They’re cranks, creating their own grand-sounding organisations (and in Busby’s case, his very own “peer-reviewed journal”) to make themselves look legitimate. I believe it’s from New World Order conspiracy theorist Caldicott that you get this:

        what studies are you citing? The WHO? That organization that has to run its findings by the IAEA –dedicated to the expansion of nuclear power — before being allowed to publish them?

        This is the second time this week a JT commenter has made this insane claim. It comes from quoting one part of a sentence in an inter-agency agreement. It goes like this: “…it is recognized by the World Health Organization that the International Atomic Energy Agency has the primary responsibility for encouraging, assisting and co-ordinating research and development and practical application of atomic energy for peaceful uses throughout the world…” What your conspiracy theory websites don’t tell you is how the sentence finishes: “…without prejudice to the right of the World Health Organization to concern itself with promoting, developing, assisting and co-ordinating international health work, including research, in all its aspects.” When your sources play fast and loose with the facts like this, can they be trusted at all?

        It’s also an insane claim because of how the WHO works and how its work is received by the scientific community. It doesn’t control global health research. It pretty much reflects it. Your conspiracy theory that the IAEA controls everything it publishes appears in no scientific journal considering the WHO’s work. Why not? Because it’s just a conspiracy theory.

        Organisations like the WHO are pretty much as sound as you can get in terms of health research – and certainly better than conspiracy websites. I think you’re allowing your entirely justified hatred of TEPCO management to addle your thoughts. The actual extent to which the leaks from Fukushima are going to harm people is now independent of the fact that TEPCO’s criminal negligence caused them to happen. Moral failings, no matter how outrageous, are not carcinogenic in themselves.

  • spectral_ev

    You could read this as 1 in 100 people tested had evidence of internal exposure to radiation. Not good when you consider the lifetime effects of radiation damage.

    • Yes, 1 in 100 had evidence of INCONSEQUENTIAL internal exposure to radiation. That is how this SHOULD be read. Or do you write headlines for American or British “newspapers”?

      • thedudeabidez

        Note that the threshold used was 300 bq per body. In Germany similar studies used a the threshold of 20 bq, so this is roughly 15 times the European level for determining exposure.

      • Ken Yasumoto-Nicolson

        Since the figures in the article look a bit funny, I decided to go to the source, this paper:

        The article here says “300 becquerels per kilogram of body weight”, but looking at the published paper it is “the detection limit of 300 Bq/body”. I don’t know where you get your threshold of 20Bq, or indeed the article’s “For the remaining 1 percent, or 212 people, 10 becquerels were detected”. Children were also being tested, so an average weight of 30 kg would give us, perhaps, at least 10 Bq per kilogram.

        We also have the original Japanese paper to look at:

        Interestingly, Table 2 shows us that although 1% of adults in 2012 had cesium detected, only 0.09% of children did.

        Furthermore, the two graphs on the right of Figure 6 shows us that the average detected in Bq/kg was approximately 10, which explains the strange sentence I highlighted earlier.

        Therefore, I conclude that your German figure is 20 Bq/kg, so you are not comparing like with like.

      • The threshold given in the article is a mistranslation, the original Japanese report reads “300 Bq per body”, not 300 Bq per kilogram of body weight. Assuming an average body weight of 50kg, that works out to 6 bg/kg. For the “one percent” that tested higher, that would be at 10 bq/kg (otherwise the numbers don’t make sense, showing the error in translation of the “300 Bq/kg” measurement).

    • Guest

      I believe those 1% include adults eating the wild plants and wild games that feed on the wild plants that grow in the mountain in the polluted area. BTW, they do it at their own risk, knowing the consequence ( and no one has the right to stop them). Note that no children are among the polluted in the recent data.
      I guess we all should read the original paper before making assumptions.

    • aaa

      Those 1% include adults eating wild plants and games living in the
      polluted area that feed on such plants. Btw, they do it at their own
      risks, knowing about the possible consequence, if any (and no one has
      the right to stop them from eating whatever they like). Note that no
      children are among the detected in the recent data.

      We should probably all read the original paper before we make any assumptions.

      • It was only four people who tested high and were doing that. There was a news special recently about boar in the affected area, and how the meat was “well in excess” of what was considered safe by Japanese standards for cesium. They showed the numbers for something like 2 dozen boar that had been hunted and tested, while only 2 or 3 of the boar were at or below the Japanese level conversely only 1 or 2 were above international standards (US, European and IAEA) for what was safe to consume. And even then, only just over the line.

        In other words, in pretty much any other country health officials wouldn’t be worried about eating that boar meat.