Fukushima’s Incredible Death Toll

Tuesday, June 11th, 2013

The Fukushima disaster has had an incredible death toll — zero. And no one’s likely to die, either:

The committee has had two years to build a fuller picture of radiation dosages (measured as mSv) and impacts. It finds most Japanese in the first and second years were exposed to lower doses from the accident than from natural background radiation’s 2-3 mSv a year.

Also, “No radiation-related deaths or acute effects have been observed among nearly 25,000 workers involved at the accident site. Given the small number of highly exposed workers, it is unlikely that excess cases of thyroid cancer due to radiation exposure would be detectable.”

Those workers, who were allowed a maximum short-term dose of 250 mSv, have been closely monitored. Of 167 exposed to more than the industry’s recommended five-year limit of 100 mSv (a CT scan exposes patients to up to 10 mSv), 23 recorded 150-200 mSv, three 200-250 mSv and six up to 678 mSv, still short of the 1000 mSv single dosage that causes radiation sickness, or the accumulated exposure estimated to cause a fatal cancer years later in 5 per cent of people.

So, not even one case of radiation sickness to report.

A swift evacuation of 200,000 residents within a 20-kilometre radius of the plant helped protect them – WHO estimated most residents of Fukushima prefecture received doses of 1-10 mSv in the first year. By August 2011, however, the dose rate at the plant boundary was only 1.7 mSv a year.

The rapid decay of most of the radioactive material (iodine-131, which reduced to a 16th of its original activity in a month) also means the evacuated area has not been permanently blighted. Many residents have returned, although some areas have restricted entry until radiation drops below the 20 mSv-a-year threshold, expected in 2016-17.

Nor has the environment been devastated. The report says: “The exposures on both marine and terrestrial non-human biota were too low for observable acute effects.”

The quake and tsunami damage is the real catastrophe.

About 1000 deaths have been attributed to evacuations. About 90 per cent were people older than 66, who suffered from the trauma of evacuation and living in shelters. Sadly, those of them who left areas where radiation was no greater than in naturally high background areas would have been better off staying.

Let’s be clear, Fukushima was hit by a worst-case scenario: the world’s fifth-most-powerful earthquake since 1900, a tsunami twice as high as the plant was built to withstand, and follow-up quakes of magnitudes 7.1 and 6.3. A Japanese commission of inquiry described it as a “man-made disaster” because of regulatory failure and lack of a safety culture.

This “perfect storm” hit a nuclear plant built to a 50-year-old design and no one died. Japan moved a few metres east during a three-minute quake and the local coastline subsided half a metre, but the 11 reactors operating in four nuclear power plants in the region all shut down automatically. None suffered significant damage. (The tsunami disabled Fukushima’s cooling system.)

Yet such is the imbalance of dread to risk on matters nuclear that this accident was enough to turn public opinion and governments against nuclear power. Never mind that coal mining kills almost 6000 people a year, or that populations of coal-mining areas have death rates about 10 per cent higher than non-mining areas, or that coal emissions drive global warming.

And surely the fact that the more modern Onagawa nuclear plant was twice as close to the quake epicentre and shut down as designed, without incident, counts for something.


  1. Stretch says:

    Yet Germany shut down all its reactors.

  2. In the long run, we’ll learn.

    Well, those of us who are left.

  3. Slovenian Guest says:

    It does appear so, Stretch, except for the fact that Germany actually extended the lifespan of ten reactors. Units that were on schedule for decommission in 2014 will be kept running until the theoretical complete planned exit in 2022. But 2022 is many cold winter aways, so who knows…

    It was a rather brilliant political move. The source for this is a Der Spiegel graph. Luttwak himself would be so proud…

  4. Candide III says:

    The rapid decay of most of the radioactive material (iodine-131, which reduced to a 16th of its original activity in a month) also means the evacuated area has not been permanently blighted.

    Pfui. The person who wrote this is an ignoramus. The main concern is the contamination by isotopes of caesium, Cs-134 and Cs-137, having half-lives of 2 and 30 years. The evacuated area is semi-circular (on account of the sea) 10, 20 and 30km in radius, different restrictions apply to different zones, and just as in Chernobyl accident, the contamination is highly nonuniform because it is determined by the direction of the wind and by the occurrence of rainfall. In Fukushima, the main trail goes north-west from the station, that is where the most contaminated areas are. The trail extends considerably beyond the 30-km zone, and this is now reflected in evacuation/restriction designations. E.g. in the village of Iitate, the southern parts are sufficiently contaminated that a person living there would be exposed to 10-30 times the natural background. It will take 100 years to get back to something resembling normal levels. Moreover, many plants concentrate caesium and crops would be unsuitable for regular consumption for the duration.

    Now about the risk from radiation. Briefly, the UNSCEAR estimates of additional dose-related cancer incidence are likely correct. Here is a good simple review of the linear no-threshold model, which is still used, despite some objections, to estimate collective doses. In Fukushima, given evacuation we cannot reasonably expect to detect any additional radiation-induced cancers because the expected number of cases will be too small to be detected by epidemiological methods — i.e. the statistical power will be insufficient. The same situation obtains in the case of Chernobyl disaster, although the lack of proper epidemiology is partly to blame. The only potential exception in both cases is child thyroid cancer, which clearly grew by more than an order of magnitude after the Chernobyl disaster.

    However, concentrating solely on the death toll from radiation sickness or cancer is a serious mistake. Evacuation itself is a potent source of additional stress, with livelihoods and local communities irreparably ruined — something to consider even if you discount the medical effects. Irrational fear of radiation is another known source of stress (as a rule, few STEM PhDs live in the affected areas), and even in Japan evacuees are sometimes shunned and feared, just as if radiation were a sort of plague. Except in the worse-contaminated areas, local people may have been better off not knowing anything and staying put rather than being scared and evacuated.

    And in any case, why should we continue to rely on nuclear power? It’s not particularly cheap, not particularly safe*, it has its peculiar and very difficult problem of long-term storage of nuclear waste, and the technology is 60 years old already. Let’s do something more exciting, like space solar.

    * — please tell me how many people die each year in oil- and gas-drilling related accidents. The famously high coal mining figure includes accidents in China and ex-USSR, where coal is mined on the cheap and sometimes by semi-slave labor.

  5. SDF says:

    “Like space solar.”

    Or unicorns.

  6. Candide III says:

    SDF, you forgot the troll tags.

    Oh, and I forgot to mention that cancer induction times are on the order of 10 years after radiation exposure, so the fact that there were no radiation deaths among liquidation workers only proves a modicum of competence in operation management. It’s not really that difficult to give people personal dosimeters and check them every day.

  7. Buckethead says:

    If we could figure out a way to extract energy from unicorns, that would be awesome.

    Locating and developing a reliable source of unicorns to meet our power generation needs might be problematic, though.

  8. Candide, you asked about fatalities in the oil and gas industries, so you might be interested in this CDC report on fatal injuries in offshore gas and oil operations. The answer appears to be that these activities are about 7X as dangerous (when counted by fatalities) than the average American job, with 128 fatalities between 2003 and 2010 in the US.

    Also, UNSCEAR appears to have dropped the LNT model, in part due to the data coming out of the Fukushima incident.

    With regards to a rational weighing of the dangers of nuclear energy, I’ve always thought a big part of it has to do with how the results of nuclear incidents are concentrated tightly in time and space compared to those of other power generation options. As you know from your study of battlefield psychology, Isegoria, a unit that suffers 10 casualties in 1 hour is far more likely to break than one that suffered 10 (or even 15) casualties in 10 hours.

    I’m also quite enthusiastic about space solar, and I think the exponential improvements we are presently experiencing in automation technology will make large-scale space industrialization viable far sooner than most people seem to think. However, it’s not something to depend on for the immediate (20 yr) future.

  9. Candide III says:

    Scipio, thanks for the figures. 7X the average American job does not sound like much really, and if we exclude various paper-pushing and electron-pushing jobs, or take so boring a job as truck driver for comparison, the factor will be even lower.

    UNSCEAR did not drop the LNT model completely, partly because there is nothing to replace it with, and partly because the balance of evidence is still in its favor. You might have noticed in that UN document that the phrase is “within a population exposed to incremental doses at levels equivalent to or lower than natural background levels”, whereas I was talking about levels more than an order of magnitude above background, and did not take into account the internal exposure (from consumption of local food and water) at all. I believe I know why UN had to write that; some environmental NGOs like Greenpeace have been prone to making extremely exaggerated estimates, based on LNT, of world total deaths from the Chernobyl accident, nuclear testing etc. in the hundreds of thousands, grabbing headlines and scaring people for no good purpose, when there is no epidemiological data to back up such estimates, and no prospect of getting any. As an aside, that UN document could not have been influenced by the data coming out of the Fukushima accident simply because not nearly enough time had elapsed (it still hasn’t and won’t have elapsed for 10-20 years). The document was accepted by UN at the end of May 2012, which means it was prepared way before that, most likely in 2011.

    About the dangers of nuclear energy, yes that’s a part of it, and another part is that the danger is invisible and incomprehensible (lack of STEM PhDs again). But an even greater part is the influence of factors other than direct radiation exposure, see my comment above. Imagine for the sake of the argument that the wind had blown to the south instead of west and north-east after Chernobyl, and it had rained on Kiev instead of marginal agricultural communities in Ukrainian and Belorussian Polesye. A city of three million people would have had to be evacuated and left substantially uninhabitable for decades. Coal mining doesn’t do that. Or had the weather been slightly different after Fukushima, Fukushima city might have gotten the 50mSv/y fall-outs and would have had to be evacuated, that’s 300,000 people and 800km² of land. Japan’s total area is 340,000km² and 90% of that is unsuitable for building or cultivation. 800km² out of 40,000km² is 2% — quite a blow, especially when you can’t compensate it by colonizing the mainland.

    In the immediate future, Japan is quite comfortably supplied by hydrocarbons, whether imported or their own methane hydrates (look up Chikyuu exploration).

  10. Ben says:

    One dead. I’m pretty sure it wasn’t Fukushima-related though.

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