How dangerous is the Fukushima exclusion zone?

With the situation at the stricken reactors of Fukushima Daiichi nuclear power plant now relatively stable, the longest-term and most concerning aspect of the disaster in Japan is the exclusion zone, which has displaced thousands of people from their homes, villages and schools due to the danger of radiation. Needless to say, this is adding enormously to the misery and trauma of the earthquake and tsunami. In this article I examine what science can tell us about whether the exclusion zone is really needed, and how risky the radioactive fallout around Fukushima likely is in comparison to other dangers.

In recent days some anti-nuclear groups have been insisting that the evacuation zone should be expanded, that the situation is more dangerous than conventionally believed, and that official sources should not be trusted. This I believe flies in the face of the main lesson from the world’s worst civil nuclear disaster – Chernobyl in 1986 – which demonstrated convincingly that the fear of radiation, and the social and pyschological trauma suffered by irradiated ‘victims’ is at least as, and probably more, dangerous than the physical and biological impact of the radiation itself.

The expert report released by the Chernobyl Forum (comprising eight UN agencies, including the World Health Organisation, as well as the governments of Belarus, Ukraine and Russia) came to the following important conclusions:

Poverty, “lifestyle” diseases now rampant in the former Soviet Union and mental health problems pose a far greater threat to local communities than does radiation exposure.

Relocation proved a “deeply traumatic experience” for some 350,000 people moved out of the affected areas. Although 116 000 were moved from the most heavily impacted area immediately after the accident, later relocations did little to reduce radiation exposure.

Persistent myths and misperceptions about the threat of radiation have resulted in “paralyzing fatalism” among residents of affected areas.”[i]

In other words, as the Chernobyl Forum states, the mental health impact of Chernobyl was “the largest public health problem created by the accident” – a conclusion of great significance for Fukushima[ii]. In particular, this suggests that ideologically-motivated anti-nuclear campaign groups – some of which continue to stir up scientifically unwarranted fear of radiation in the affected Japanese population[iii] – may increase the trauma of the displaced people, and worsen their mental and physical health as a result. So far as I can tell, none of the campaign groups currently operating in the area, or those issuing wildly-inflated estimates of the likely eventual death toll, realise that their activities are likely to worsen the overall suffering of the Japanese people.

This is not to suggest that the levels of radiation now being measured in the exclusion zone, and some heavily-contaminated areas beyond, are inconsequential. In fact, the latest (August 7) radiation readings released by the Japanese ministry of science[iv] reveal that substantial radioactivity persists even outside the exclusion zone. At Iitate village, for example, which has some of the highest readings on the survey, a measurement of 133 millisieverts per year (mSv/yr) was taken. In general, most of the several dozen readings come in at the 1 to 10 mSv/yr range, though with the highest of all (at Namie town, 24km north-west of the stricken reactors) at 289 mSv/yr. (The Japanese authorities provide readings in microsieverts per hour, so to convert to millisieverts per year I have multiplied by 8760 and then divided by 1000.)

Here we need some context. What do these figures mean? On a global average we are all exposed to 2.4 mSv/yr of background radiation in the environment (though this varies geographically by an order of magnitude or more mainly depending on local geology), so for most of the exclusion zone around Fukushima, levels of radioactivity are only a few times higher than would naturally be expected. Even the Namie town readings are not unprecedented – in Ramsar, Iran, naturally-occurring radon in the surrounding areas leads to exposures as high as 250 mSv/yr for the local population, without any reported health effects[v].

Does this mean that everyone can forget about the radiation and return home? Not necessarily. The precautionary limits set internationally and by the Japanese government exist for a reason. The scientific consensus is that, as stated by the ‘linear no threshold’ hypothesis, there is no safe dose for radiation – so even a small increase in radioactive dose will lead to an equivalent small increase in cancer risk, and this risk needs to be properly considered in safety assessments. However, it also needs to be set against the risk of health impacts and other trauma suffered by people who are not allowed to return to their homes and suffer permanent displacement. Which risk is worse?

The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR, which can be considered a sort of IPCC for radiation risk science and reports to the UN General Assembly) concluded in 2010 in a report on ‘low-dose radiation effects on health’[vi] that a dose of 100 mSv (stated as 0.1 grays – we can consider grays and sieverts as roughly equivalent here) would lead to between 3 and 7 additional deaths from cancer per thousand people over their lifetimes. For leukaemia the additional lifetime risk is 0.3-0.5 additional deaths per thousand. So if the UN experts are correct, people moving back into heavily-irradiated zones like Iitate and Namie town can expect additional cancer mortality risks in this sort of range.

Another authoritative source, which also considers the ‘linear no threshold’ precautionary model to be the most scientifically-justified, is the 2006 US National Research Council report entitled ‘Health Risks from Exposure to Low Levels of Ionizing Radiation: BEIR VII Phase 2’[vii]. The expert committee of authors calculates – based on their modelling work – that 10 people in 1000 would be expected to develop cancer (but not necessarily die from it) resulting from a dose 100 mSv above background. At a lower dose, of 10 mSv, the committee predicts an additional cancer incidence of 1 case per thousand. For context, about 420 people in a thousand (in this US case) will develop cancer anyway. This means that identifying additional radiation-induced cancers is statistically extremely challenging, and explains why multiple epidemiological studies have so far failed to find unambiguous evidence of increased cancer incidence at low doses even around Chernobyl (with the important exception of iodine-131-induced thyroid cancers).

So the scientific consensus currently is that the radioactivity released by the accident at Fukushima will very likely present a small additional lifetime risk of cancer for people whose homes are in the relatively high 10-100 mSv contamination range. Given that the contamination comes largely from caesium-137 (which has a half-life of about 30 years) this will persist for long enough to make permanent evacuation a worrying prospect. Think about it seriously: would you return to your home if doing so presented you with a one-in-a-thousand to one-in-a-hundred additional risk of cancer? This is the choice faced by the Japanese population and authorities.

The issue of relative risk is central to addressing this choice rationally. Many people around Chernobyl have decided that they would rather face an undefined (but potentially larger) additional risk and have unofficially returned to their homes already – rather than live miserable lives in permanent exile. We all face risk in everything we do, of course, and the additional risk presented by radiation is small in comparison both to the background statistical risk of getting cancer anyway. It should also be considered alongside the carcinogenic risks presented by other activities like smoking, consuming alcohol, eating a lot of meat and so on.

There are also risks presented by the voluntary exposure to radiation we subject ourselves to, where the small additional risk is considered lower than the potential medical benefit. A single CT whole-body scan gives an effective dose of 12 mSv, which – like any other radiation – adds a small amount to one’s lifetime risk of getting cancer. One scientific study on the subject estimates an additional cancer mortality risk of 0.8 in 1000 for a 45-year-old patient undergoing a CT scan [viii]. (An estimated 62 million CT scans are performed each year in the US, including 4 million on children[ix].) The study estimates that were the same adult to undergo annual CT scans until age 75 – giving them similar exposure to living in Fukushima-contaminated areas with radiation doses of 10mSv/yr – the additional risk of cancer mortality would be about 1.9%, or 19 in 1000. By comparison, an individual’s lifetime chance of dying in a traffic accident in the US is estimated at 1 in 77 (or 13 in 1000).

For the purposes of argument, therefore, if everyone living in the exclusion zone (and other severely-contaminated areas) could be persuaded to give up driving (and to eschew smoking, which presents a massive lifetime risk of 100 in 1000 of causing lung cancer) then everyone could in theory be allowed to return with no additional loss of life to the impacts of radiation. The risks could simply be traded off each other. One could also make a strong case that people living in the Fukushima exclusion zone would still be better off statistically than those in heavily-polluted city centres, near coal-fired power stations and in industrial zones, which likely present higher carcinogenic risks.

Indeed, these risks were quantified and compared in a fascinating 2007 paper published in BMC Public Health journal (open access, h/t ColinG, [x]). In it the author looks at the comparative risks of obesity, smoking and exposure to radiation – in terms of ‘years of life lost’, a male smoker can expect to lose 10 years of life, an obese white male 1-4 years of life, as compared to an average 2.6 years of life lost for Japanese atomic bomb survivors who had experienced the highest doses (2.25 Gy – for gamma radiation such as released by an atomic bomb, sieverts and grays are roughly equivalent, so the dose can be thought of as 2,250 millisieverts; about ten times higher than current doses anywhere in the Fukushima exclusion zone).

An equally useful comparison made by the author considers whether air pollution in city centres, passive smoking or radiation contamination from the Chernobyl accident are more dangerous. He finds that living in a polluted city (e.g. London, as compared to lightly-polluted Inverness) yields 2.8% mortality (28 per 1000), passive smoking 1.7% mortality, whilst radiation exposure of 100 mSv in the Chernobyl zone yields a mortality risk of 0.4% (4 per 1000). This latter risk is clearly on the same scale as the US scientific committee which calculates a 3-7 per 1000 risk of mortality for 100 mSv, and obviously compares rather favourably with the 28 per 1000 mortality risk for living in a polluted area. This raises the intriguing possibility that – if these calculations are correct – lives would be saved by moving people out of central Tokyo and into the more contaminated areas of the Fukushima exclusion zone.

This is in fact exactly the conclusion reached by the paper’s author:

The increased mortality rate of the populations most affected by the Chernobyl accident may be comparable to (and possibly lower than) risks from elevated exposure to air pollution or environmental tobacco smoke. It is probably surprising to many (not least the affected populations themselves) that people still living unofficially in the abandoned lands around Chernobyl may actually have a lower health risk from radiation than they would have if they were exposed to the air pollution health risk in a large city such as nearby Kiev.

Of course, real people do not base their risk assessments on scientific numerical quantifications such as this. There are also ethical issues in that obesity or living in a polluted city can be considered a personal choice, whilst having a nearby nuclear power station suffer a triple meltdown is something imposed on a population not used to such a danger. But the trading-off of risk is unavoidable, and the experience of Chernobyl shows that permanent exclusion from their homes and communities is also extremely damaging to people’s health, and increases mortality rates from ‘lifestyle’ causes such as suicide, alcoholism and so on. In addition, when people are labelled ‘victims’ and told they are doomed to die of cancer, an increased number may indeed suffer a psychologically-induced ill-health.

Naturally it will be extremely difficult for the Japanese authorities to make a decision about how far to relax the exclusion zone that has been set up (though the process of reaching this decision has already been cautiously begun[xi]). People are terrified of radiation – far more terrified than they are of traditional sources and activities which present a much greater statistical risk of causing cancer – and the activities of anti-nuclear campaigners in the area has doubtless increased this sense of terror. It has also added to the distrust of experts in general and the government in particular, despite the need for decision-making to be based on a scientific approach to real risk rather than the terrors imagined by an already-traumatised population.

In the final assessment we also need to remember the wider catastrophe of March 11 of which the nuclear disaster is only a small part. More than 20,000 people died as a result of the tsunami, and none have so far died or been injured because of the events at Fukushima Daiichi. I hope also that the continuing media and official attention being given to the nuclear crisis does not distract from the needs of those displaced (also perhaps permanently), bereaved and traumatised by the tsunami. And, as I have argued elsewhere, it is equally important that the accident at Fukushima does not lead to a hasty abandonment of nuclear power both in Japan and other countries, resulting in a return to the vastly more dangerous energy source of coal. For the sake of all those affected by this desperately unfortunate sequence of events, the Japanese government must continue to take a rational approach to risk, build up the trust of its people and resist the demands of both media hysteria and ideological campaign groups.













  1. ColinG

    One of the most useful papers I have found for comparing the risk of radiation exposure is this one:

    “Are passive smoking, air pollution and obesity a greater mortality risk than major radiation incidents?”

    Would you live in a city if you ran a 1-in-35 lifetime risk of death from the air pollution? Whether people realise it or not, the implicit answer to this for most individuals is “yes”. Most of the area inside the Fukushima exclusion zone is this safe or safer.

    As the paper concludes: “It is probably surprising to many (not least the affected populations themselves) that people still living unofficially in the abandoned lands around Chernobyl may actually have a lower health risk from radiation than they would have if they were exposed to the air pollution health risk in a large city such as nearby Kiev.”

    1. Mark Lynas (Post author)

      Thanks for the link, Colin – I’d missed this paper. I’ve added a couple of paras to the article above – very useful, thanks.

    2. ColinG

      You’re welcome.

      It is interesting to oberve the double-standard between air pollution regulation and radiation regulation.

      PM2.5 pollution is measures in µg/m3. The BMC paper bases its 2.8% mortlaity risk for air pollution on a rather conservative figure of 6.9µg/m3.

      In fact the EU target for air pollution is a whopping 25µg/m3 (and this is a limit which is regularly exceeded).

      Extrapolating from the BMC artcile, the lifetime mortality risk for 25µg/m3 is around 10%!!

      If radiation regulation was this lax then, even using LNT, the public limit would be around 30mSv per annum. (Giving about 10% mortality risk over 70 years)

      The obvious difference is that artifical radiation exposure is emminently avoidable most of the time, therefore it is regulated with the assumption that it can be avoided.

      Air pollution on the other hand is unavoidable as long as we burn fossil fuel, therefore the regulation is permissive.

      But it gives a false sense of threat when the radiation limts need to be raised in rare emergencies.

  2. Robin Smith

    Have you heard about Radiation Hormesis?

    Its only a theory. Yet so is the linear no threshold.

  3. Karl-Friedrich Lenz

    I find it slightly surprising that you would report “linear non-threshold” as “scientific consensus”.

    I heard about Ramsar from your earlier post on this blog first, and you mention it again this time.This is clear falsification of the LNT theory. One falsification is enough to dispose of any hypothesis.

    LNT doesn’t even make sense as hypothesis. For one, it is clearly wrong at the high end. There are readily observed thresholds of radiation doses that kill people by radiation sickness. It is also not compatible with the fact that the human body has self-healing power in all other areas (blood loss for example).

    And there is ample evidence for self-healing power with radiation. Healthy tissue around a tumor gets a whopping 30 Sv in a single month in cancer radiation therapy. If there was no healing process, that is much more than it could survive.

    Even if LNT was not clearly incompatible with natural radiation facts and implausible as a hypothesis, it is downright evil from an ethical point of view.

    As a consequence of this theory, people start to worry. That has a massive negative health effect (nocebo),. If you choose the countering hypothesis of hormesis, you replace that with a placebo effect. The LNT preachers are choosing to spread misery with their misguided efforts, where they could spread happiness.

    As you mentioned in the post, most of the damage from Chernobyl came from worrying about radiation, as opposed to actual damage from radiation.

    1. Mark Lynas (Post author)

      Hi Karl – I don’t think the Ramsar case ‘falsifies’ the LNT hypothesis exactly; yes it is evidence against, but it hasn’t been properly studied. Even according to LNT you wouldn’t expect cancer rates to be high enough in the area to be very easily visible, and I’m not aware of any proper epidemiological studies on it. Plus, there does seem to be evidence from other radon studies of small increases in lung cancer (and larger ones for smokers) so this is some evidence that even ‘natural’ radiation is dangerous – though of course less dangerous than many other things we all take for granted.

    2. ColinG

      Mark, bear in mind that Ramsar is 250mSv YEARLY.

      Over a lifetime of say 60 years that is 15,000mSv. LNT says that the mortality risk should be around 75%. The majority of people should die of cancer. That should be observable but it is not.

      In fact your UNSCEAR link says: “…studies on human populations living in areas with elevated natural background radiation in China and India do not indicate that radiation at such levels increases the risk of cancer”

      So clearly LNT does not apply there.

      The more you look at the way that radiation interacts with cells the more obvious it is that a linear model can only ever be a very gross approximation of what is going on. The chances of it being correct at low levels are virtually zero. LNT is possibly a useful conservative safety guide for individuals, but it is not appropriate for predicting the outcome of low-level of exposures to large populations. (In fact UNSCEAR says as much in their Chernobyl report.)

    3. Karl-Friedrich Lenz

      I have gone digging up some papers in addition to the one cited in the post above on the issue of Ramsar:

      Hendry and others, Human exposure to high natural background radiation: what can it teach us about radiation risks?, Journal of Radiological Protection 2009,

      They confirm the point made by Mark Lynas above that there are no “proper epidemiological studies”. The problem with Ramsar is that the population is so small that an 0.5% risk increase would not show up with any statistical significance.

      Mosavi-Jarrahi and others, Mortality and morbidity from cancer in the population exposed to high level of natural radiation area in Ramsar, Iran, International Congress Series 2005,

      They have looked at the cancer mortality data and found actually less risk in the higher level areas, but with so small absolute numbers that there is no way to “falsify” LNT with that.

      It does falsify LNT for the idea that 15 Sv over a lifetime should lead to 75% cancer rate though, as pointed out above by ColinG.

    4. Mark

      Yes – indeed, ICRP 103 states that collective dose should NOT be used to assess fatal cancer risk in a large population.

  4. Rod Adams

    Mark – excellent commentary. As Karl-Friedrich Lenz points out, my only real quibble is your description of the LNT as the scientific consensus. Its real status is that it is the accepted legal basis for regulations, but that decision is made by bureaucrats, not by scientists. (Some of the bureaucrats might have scientific degrees, but that does not necessarily qualify them as practicing and publishing scientists.) Here is a link to the Health Physics Society position statement on risk assessment –

    One more thing that is worth mentioning – fear of something that is hard to sense and produces only long term effects the reality of which is difficult to determine is NOT natural. Members of developed societies have been carefully taught to be afraid of radiation.

    I believe that the expensive, long-term effort to teach fear of radiation has been funded mainly by people who wanted to keep making money by selling coal, oil and natural gas.

    1. Mark Lynas (Post author)

      Hi Rod – thanks for this. As I mentioned on twitter (!) I agree that there is a strong case against LNT, very persuasively put by Prof Wade Allison in his book ‘Radiation and Reason’. But… I took a strategic decision to be conservative here in interpreting the ‘scientific consensus’ on this – and the US National Academies committee (which is composed of all sorts of scientific luminaries) is very clear in rejecting both hormesis and threshold hypotheses.

      So I am trying in the piece to give some relative sense of equivalent risks, but in doing so I thought it would be more persuasive to people if I went with the most conservative and precautionary view rather than backing a minority perspective that radiation at low levels is either not dangerous or positively beneficial.

      Hope this makes sense.

    2. Rod Adams

      Mark – Science is not subject to voting.

      In the case of the LNT, long term evidence overturns the assumptions as documented by Allison, Luckey, Pollycove, Cohen, Rockwell, Muckerheide, Cuttler, and dozens more.

      Unfortunately, membership on the BEIR committees is largely controlled out of a single office called Office of Radiation and Air/Office of Radiation and Indoor Air/Radiation Protection Division that buried deep inside of the US Environmental Protection Agency.

      That office controls the purse strings for the Life Span Studies (LSS) of the Hiroshima survivors. If you read the BEIR VII report, you will find many references to the data from that study. You can find many other sources that refer to it with the search term of Hiroshima LSS.

      There are a couple of lifelong bureaucrats who determined several decades ago that they would build their career on ensuring that the LSS kept getting funded year after year until the very last survivor died and the data could be fully “analyzed.” One of those bureaucrats finally retired a couple of years ago, but the other one – remains firmly ensconced in his position and absolutely blocks the appointment of anyone who questions the assumption from getting funded or from joining the committee.

      Would you be interested in the bureaucrat’s name and phone number so that you can ask some questions that would validate my interpretation? You’ll need to use your best investigative journalistic techniques, he will most certainly not admit to his strategy directly.

      (I have a source. You have my direct email address.)

    3. Mark Lynas (Post author)

      Hi Rod –
      I’m not sure about this. I mean, looking at the a-bomb survivor data studies, including various papers by Preston et al, they seem to conclude clearly that LNT holds up according to the data. Allison has the same data and reaches a different conclusion… so my judgement was to follow the most mainstream approach for the purposes of the article above. However, I retain a very open mind on LNT generally.

      I’ll leave digging on the BEIR bureaucrats to someone better informed about the whole issue than me!


    4. Julian

      Is Hiroshima a good case study for LNT though? Unless I’m mistaken, the vast majority of harmful radiation was released in a single burst, in the form of gamma rays and neutrons released by the explosion. The amount of fission products released was fairly small (I think on the order of 30 grams of caesium-137 was released) and probably not significant in the radiation exposure suffered by the citizens of Hiroshima. This is not compatible with the situation of a nuclear meltdown and subsequent release of nuclear materials where the rate of exposure is low over a long period, compared to a nuclear bomb where the rate of exposure is very high but over a very short period. The fact that LNT held up with Hiroshima does not necessarily falsify hormesis as it doesn’t really make claims about bursts of exposure. To my knowledge, it could very well be that a continous100 mSv/y exposure does no harm at all, but that an instantaneous dose of 100 mSv does cause a statistically significant amount of damage.

    5. Rational Debate

      Hi Mark,

      A Bomb studies really don’t work for supporting LNT at any dose below what we would consider to still be very high doses, because of several factors. Not in any particular order, just a few aspects that come to mind right off…

      Dose reconstructions were very difficult, even more so for those who received low doses.

      Many other factors drastically affected the health of survivors, including severe starvation, other environmental exposures, disease, etc.

      For all intents and purposes, it was an acute exposure. More often than not by the time we are talking concern over low doses, it’s not from acute exposures anyhow.

      And so on… the A Bomb data helps ‘fix’ (to some extent) the upper end of the curve, but really isn’t very useful for trying to determine if there is or isn’t a threshold effect.

    6. Mark

      You link the bomb data to longer term, low dose and low dose rate by the DDREF (Dose and Dose Rate Effectiveness Factor) – ICRP. Potentially a lot of finger in the wind (DDREF is 2 ).

    7. David Lewis

      Rod Adams also believes civilization could still be using CFCs, because they don’t threaten the ozone layer. He believes scientists don’t actually measure what is in the atmosphere – one crackpot comes up with a stupid theory and the rest latch on to it without confirming by observation. He explains himself on his own blog.

      The Bulletin of Atomic Scientists recently published, in May/June 2012, a special issue on low-level radiation risks which contains a number of articles discussing LNT. The publisher states that the issue exists to “examine what is new about the debate over low-dose radiation risk”, calling the issue an “update of the existing literature”. The guest editor, Jan Bayea, states her goal was to give readers “a broad-based view of the epidemiologic evidence and its differing interpretations”.

      Rod seems to think the entire scientific establishment studying radiation as well as atmospheric science is made up of corrupt individuals uninterested in what reality is.

  5. Rod Adams

    Mark – the purse strings that the BEIR bureaucrat that I mentioned holds are the funds for the a-bomb survivor studies. He is the guy who gets to decide which studies get support from the US government and which do not.

    That is why his opinion and his actions are so powerful in this discussion.

  6. Konstantin


    I find it confusing that the article keeps switching back and forth between one-time doses (mSv) and yearly doses (mSv/y).

    For example, the article quotes research saying that a dose of 100 mSv might cause additional 3-7 cancers per 1000 people. But for some of the contaminated areas, this is less than a yearly dose. If someone in his 30s (with the assumed remaining life expectancy of 50 years) moves to such an area, he would collect 5Sv over these 50 years.

    How does the cancer probability scale up with the accumulated dose? If it happens on a linear scale too, then we would have to expect additional 150-350 cancers per 1000 people in the next 50 years! This is quite a significant risk.

    When you compare the risk to polluted cities, it seems to me that you are comparing a lifetime risk in a polluted city (2.8%) to the yearly risk in radioactive areas (3-7 cancers per 1000 people per year of irradiation).

    So it would appear to me that living in the Fukushima fallout area could be over 10x more risky than living in a polluted city for the same duration. Assuming I understood the figures you quoted correctly.

    1. Mark Lynas (Post author)

      You are quite right that this is an issue. I find this is also a problem with a lot of the literature on this! The BEIR National Academies report is talking about a one-time dose of 100 mSv, as the article states – so you are right to question what this is in terms of a cumulative dose over a lifetime. My understanding though is that you cannot just multiply the one-off dose by the number of years, because biological systems repair themselves and so on.
      After all, the LNT extrapolations about the a-bomb survivors are also for a one-off dose.

      If you think about it, the a-bomb survivors experienced 100 mSv (or whatever) over a matter of seconds, whilst someone living in an area which delivers this in a year experiences a dose rate which is thousands of times lower (because there are 31,536,000 seconds in a year), and therefore more able to be tolerated by the body. Indeed, the Japanese figures I quote for Fukushima are measured in microsieverts per hour for this reason.

      The 2007 Smith paper I quote above says the following:

      “The ICRP risk estimate [15] assumes a dose and dose-rate effectiveness factor (DDREF) of 2.0 (reducing predicted risk by a factor of 2.0) for extrapolation of the data from the bomb survivors (who were exposed at extremely high dose rate) to lower dose and/or dose-rate exposures. “Low dose” has been defined as < 100 mSv [14], though there is no precise definition. Some assessments of cancer mortality following Chernobyl (e.g. [11]) did not apply a DDREF, whilst others did (e.g. [16]). The present study uses the ICRP risk estimates which include a DDREF, but where appropriate it is noted that risk predictions would be increased by a factor of 2 should the DDREF be excluded." So basically factor is included in order to convert a one-off dose into a long-term exposure in this study at least, but doing so actually reduces the calculated risk - the reverse of what you are concerned about. I would welcome comment from other experts who could help shed some light on this.

    2. ColinG

      Mark, i am no expert on this but I have done some reading and my understanding is that strict application of the LNT model simply requires doses to be added together exactly as Konstantin suggests.

      (The only mitigating factor in a situation like Fukushima is that the dose rate will reduce over time as the isotopes decay and as the area is hopefully decontaminated. It is unlikely that any inhabited area would remain at 100mSv/yr for many years. In fact the aim is to get as much of the area down to 1mSv/yr as soon as possible.)

      One of the attractions of the LNT model from a regulatory point of view is that it is very easy to calculate cumulative dose when the dose rate does not matter. Simply add up any exposures to get the total, regardless of the time period or rate.

      The DDREF is a fudge factor introduced to make the linear model fit the data for very high acute dose rates.

      At high dose rates (for A-bomb survivors) the line is steeper than for experimental observations where the same high dose has been administered over a longer period. Hence some studies use a DDREF to reflect that fact that chronic exposure evidently has less risk even though the total exposure might be the same.

      The graph at the bottom of this page shows how two different straight lines might be used to fit the observed data into a “linear” model:

      But as far as I am aware all chronic exposure is treated the same way. So getting 3mSv per year extra for 70 years from living in Aberdeenshire (where natural radiation is about double UK average) is functionally equivalent to receiving about 200mSv excess in mid-life over a few months working as a liquidator at Chernobyl.

      And living your life in Ramsar really should kill you. (But it doesn’t.)

      This is quite obviously a crude approximation of reality; and at low levels the uncertainties are so great that it is almost meaningless. But LNT makes for easy book-keeping if doses can simply be added together to calculate a cumulative risk.

    3. Joffan

      Colin, DDREF is a fudge factor to try to make very LOW doses and dose-rates fit to a modification of LNT.

      Effectively the existence of DDREF is a back-door method of invalidating LNT while not admitting as much. A low-dose experiment or observation that produces no evidence of any effect can be brought within the envelope of uncertainty for the LNT model by choosing a value of DDREF to achieve this. In this way – as BEIR VII actually hints – any threshold effect is able to be ignored.

    4. peakoil2010

      Hi everybody, interesting discussion indeed:

      the calculation of the risk incurred by being subjected to external and/or internal irradiation should be carried out by specifying the radionuclides, and keeping into account their biological half-life and effective dose coefficient, which combined with the decay half-life (independent of biology, that is) gives the “average” time a given radionuclide stays inside one’s body.
      For instance, Cs-137 has a decay half-life of 30 years, but a biological one of 20 days in infants, 150 for male adults and around 120 for female adults.
      The effective dose coefficient tells us, for each radionuclide how “good” (bad, actually…) it is in terms of acting inside our body.
      Contrary to popular galore, ingesting on shot of X Bq of Cs-137 does not mean that it will reside, decay and make damage to our body for the next several half-lives (typically 10, i.e. 300 years)… it simply gets metabolised and finally excreted within typically 100-150 days. It is only during this time that it can actually damage the cells inside our body.

      In radioprotection, three separate coefficients are considered: one for immersion of the body in air containing a given activity of the nuclide, one for living on soil with a given contamination, and the third for immersion in water with a given contamination (swimming near Fukushima’s shores).

      For Cs-137 the coefficients for external irradiation are, respectively:

      2.73E-14 (Sv/s)/(Bq/m3)
      5.55E-16 (Sv/s)/(Bq/m2)
      5.92E-17 (Sv/s/)/(Bq/m3).

      This means that living in an area with a surface contamination of Cs-137 of 50 kBq/m2 generates a dose to the body of 5.55E-16*50000*86400*365=8.8E-4 Sv/year (the last two numbers being the number of seconds in a year, of course), i.e. 0.88 mSv/year, a fraction of the backround radiation, leading (according even to the flawed LNT) to an excess risk of developing a deadly cancer of 0.044%.

      For internal contamination, the coefficients are two: one for inhalation and one for ingestion. In the case of Cs-137, assuming particles of 1 micrometer diameter, the coefficients are: inhalation = 4.6E-9, ingestion = 1.3E-8, and the units are (Sv/Bq).
      Example: recently there has been news of japanese-grown tea having been retired from the market because it had been measured to be 5 kBq/kg radioactive. How dangerous is that in terms of ingested activity and related dose to the body? Let’s see… assuming one kg of tea leaves per person per year (don’t know whether that’s a reasonable value, just playing with numbers, OK?) we get 1.3E-8*5000 Sv/year = 0.065 mSv/year.

      Sorry for being a bit long… thought it could help.



      P.S.: data used above have been taken from the French IRSN database.

  7. keith haworth

    Let’s get this clear Mark, for whatever reasons – climate change et al – you are pro nuclear, and all you are doing in making these statements is to make nuclear sound safe by presenting a bunch of research theories that cannot be verified in real time. Actually they can but you have not presented the data that shows the risk of dying from cancer induced by human released radiation.
    In New Zealand I once met a German nuclear scientist who told me ingesting plutonium would not do a person any harm, and also a veterinary surgeon over there who swore that you could drink Agent Orange (245T-24D), If you believe either of these scientists to be correct, why not put your money where your mouth is and put either to the test? Personally I would be inclined to err on the side of caution, something humanity has not done to much effect in the past – thus the climate change, species extinction, resource depletions and widespread pollution of the planet

    1. Mark Lynas (Post author)

      Fair enough. But why not judge for yourself whether I’m presenting the scientific case accurately? If not, where have I got it wrong? You make strong assertions about belief… but without any evidence.

      Regarding the plutonium issue, actually I believe the late nuclear scientist Bernard Cohen did once challenge Ralph Nader to eat as much caffeine as he would plutonium. Nader turned down the offer, because of course in large quantities caffeine is deadly, but plutonium would be excreted with no obvious damage (see for more on this).

    2. Hector Balint

      Had Cohen offered to inhale the plutonium that anecdote might have some relevance.

    3. Zwitterion2

      Bernard Cohen did offer to inhale plutonium.

    4. Hector Balint

      For what its worth I think he said eat. Ingest would have sounded rather lame in the context of a TV debate. His admirers have broadened it to ingest because that’s what they’re like. Now they’re pronouncing him dead. Nobody could make that mistake about Nader.

    5. Hector Balint

      Was in fact totally wrong there. Just looking at Cohen’s “Before it’s too Late. A Scientists’ Case for Nuclear Energy.” (1983).
      Nader accused Cohen of ….” “trying to detoxify plutonium with a pen”. In response I offered to inhale many times as much plutonium as he said was lethal.” The nature of the challenge was quite complicated, he wanted to do it on prime time tv with a couple of minutes first to explain to the public what he was up to. Of course nobody was interested and Cohen recounts ruefully how he was misrepresented as a nutter afterwards.
      The book is worth reading. It’s striking how much less patronising and sanctimonious popular science writing was twenty or thirty years ago. The chapter entitled “The Fearsome Reactor Meltdown Accident” discusses the near impossibility of such an event.

    6. Barry Brook

      Hi Mark, I think if you asked Bernard Cohen about his lateness, he might well reply “Reports of my death have been greatly exaggerated”. I emailed him a while back and he’s still going strong!

    7. peakoil2010

      keith haworth says:
      “In New Zealand I once met a German nuclear scientist who told me ingesting plutonium would not do a person any harm”

      Hello Keith:

      I am sorry to inform you that the German nuclear guy was right about Plutonium. Actually, I am HAPPY to inform you.
      As a matter of fact, its ingestion is way less dangerous that its inhalation. This has been tested on animals (primates, dogs, rabbits, mice) and also on humans.
      Its so called gastro-intestinal absorption factor lays between 1.0E-5 and 5.0E-4, i.e. ingesting 1 gr of Pu will leave inside your body only 1/2 a microgram.
      It’s only in the form of Pu oxide that Pu isotopes become dangerous, and can be lethal.
      A threshold of ~1 Gy has been measured to be the lowest needed to develop lung tumors. No leukaemia is generated by exposure to Pu.

      The extrapolated (to men, from baboon and dogs) LD50 coefficients (50% of the subjects dying within a given period of time) are:

      – 21 MBq or 9.0 mg at 30 days;
      – 2.1 MBq or 0.9 mg at 1 year;
      – 0.85 MBq or 0.4 mg for 1000 days.

      Death is generally due to a secondary induced pneumonia, not cancer as usually portrayed.

      In light of these facts, it can be stated that the dangerosity of Pu has always been greatly exagerated, to suit pre/ill-conceived views on nuclear power generation (and military use of weapons, a subject I don’t want to touch here).

      Keith: if what I have written above has not convinced you, just think about this (another proven fact): if “1 microgram of Pu could kill a person” were a true statement, mankind would have disappeared since the late 50s-early 60s, as approximantely 3 and 1/2 kg of Pu have been dispersed in the atmosphere by the hundreds of nuclear and thermonuclear shots in air carried out by USA, URSS, UK, France, China, etc…
      That makes 3 and 1/2 billion micrograms, right?



    8. Global

      Indeed this is correct. Unfortunately it goes against so much of the hysteria out there. How can something so powerful it makes a nuclear bomb explode not kill you just by looking at it? Then again, being struck by lightning can kill you instantly, but we use electricity (and recieve occasional shocks) every day without serious consequence.

  8. Karen Street

    Much thanks!!!! and some tiny quibbles:

    • We can agree perhaps that Okuma, 3 km from the Fukushima Daiichi plant, >500 mSv for the first year, is worse than Tokyo?
    • Assuming that half of the cesium is Cs-134, and half is Cs-137, enough decays during the year that average dose equivalent is 92% of your calculated amount. So for the first year, divide by 1,000, multiply by 8,760, and multiply by 0.92. You can’t do that after the first year because the Cs-134 is less than half. To get the rate at the end of the first year, multiply by 0.84.
    • One worker died from a heart attack while wearing the hazmat outfit on a hot day.

  9. Jerry Cuttler

    Hi Folks

    In your deliberations on this subject, you could read several of my recent articles on health effects of nuclear radiation. There are also papers by Dr. Jaworowski that are worth considering. I’ve provided several references with Internet links below.

    Jerry Cuttler

    Nuclear Energy and Health: And the Benefits of Low-Dose Radiation Hormesis,
    Jerry M. Cuttler and Myron Pollycove,
    Dose Response. 2009; 7(1): 52-89.

    Commentary on Using LNT for Radiation Protection and Risk Assessment
    Jerry M. Cuttler
    Dose Response. 2010; 8(3): 378-383.

    Editorial: Is Airport Body-Scan Radiation a Health Risk?
    Jerry M. Cuttler
    Dose Response. 2011; 9(1): 1-5.

    Observations on the Chernobyl Disaster and LNT
    Zbigniew Jaworowski
    Dose Response. 2010; 8(2): 148-171.

  10. Giorgio Bertucelli

    Is there some radiological or oncological expert who can finally and clearly explain why radioactive exposures as high as 250 mSv/yr measured in Iran have no human health negative effects and on the contrary they could be extremely dangerous for Japanese people (forget by now the Italian people,for which the only noun “radioactivity” is synonym of death)?
    Thanks a lot for the attention.

  11. Rod Adams


    I am not a radiation health expert, but I know some people who are. Dr. Jerry Cuttler, who provided links to some of his peer reviewed papers a little earlier in this thread is one of them. For a detailed explanation, you can read through those papers.

    In short, the effect that the LNT proponents refuse to see is the way that humans and other living creatures that evolved on a naturally radioactive planet Earth have natural repair mechanisms. Our cells are constantly being assaulted by numerous influences, including ionizing radiation. Some of those influences do damage, but the vast majority of the damage is repaired and we go on living.

    If the influences are modest and within natural variations, our bodies work their magic. A little exercise is good for you; too much exertion can be fatal. An aspirin tablet every day year after year helps to prevent heart disease, taking 1000 tablets (less than three years worth of daily doses) at one time is almost always fatal.

    There is a great deal of evidence supporting the Health Physics Society’s risk assessment position statement that radiation doses of less than 10 Rem (100 mSv) should not be used to compute or predict risk.

    1. Mark

      Take a look here:

      “Basic Research Results That Do Not Support the BEIR VII Report Conclusions Regarding the Linear-no-threshold Risk Hypothesis”


  12. Paul Cohen

    Disclaimer: I am neither pro or anti-nuke. I fully understand the impact of peak oil on the energy/industrial mix, and the potential need for nuke energy as a gap filler until/if/when alternative sources of energy are available.

    I live in Tokyo. I’m not panicking, I’m not a moron, I do my research. I have no issues with low dose radiation as it pertains to me at all. I do, however, have a -2 year old son and I have serious concerns about random clouds of caesium/iodine blowing my way, and constant pollution of the all too easily disrupted food supply on this rockin’ isle we call Japan.

    I’m fully conversant with the LNT issues on both sides of the debate (and Rad Hormesis), and as far as I can there is more than enough debate from reputable scientists on both sides to say “HOLD THE JURY”. Most especially so for children.pregant women. And to be frank I’m really getting tired of nuke industry PR. To a large degree the whole #Fukushima mess is due to a colossol failure of Nuke Industry risk management, despite their decades of PR as the “Risk Management Experts”.

    The core issue is not one time dosages, it’s accumlation over time, which is stating the bleeding obvious but had to be pointed out to @Mark by a commentor.

    I have yet to get straight answer on this from any “expert” which leads to conclude the best risk management strategy is not to move my son to live in Fukushima but it is to find reliable data sources of environemtal and food chain radiation contamination that will allow me to assess and take appropriate action as necessary. Perhaps you should focus your efforts on this area, as without clean data to make decisions it’s all a lot of hot air (pun intended)

    It may well be there are generally no issues up to a certain low dose threshold, or maybe it is a case of Karl Z. Morgan “there is no safe level of radiation.”. Either way , the issue is risk mangement. Or in the case of the Nuke Industry, a massive failure of Risk Management. There, I said it again.

    Please, stop the “Blame the Victims” game of implying the general population is too stupid, dumb, and ignorant to appreciate the favour the nuke industry has bestowed on them by adding yet more pollution to an already saturated/contaminated environment. We don’t appreciate it, and anybody with half an ounce of intelligence or compassion would not either.


    “This raises the intriguing possibility that – if these calculations are correct – lives would be saved by moving people out of central Tokyo and into the more contaminated areas of the Fukushima exclusion zone.”

    I’d like to raise the intriguing possibility that Mark et al (families included) find a suitable stock of radioactive material and bury it under their main living residence so that receive the daily minimum dosage that they recommend as statistically “AOK” for everyone else. Eat your lunch kids. We know you won’t be adversely affected by stress as you are all fully on board with the no-LNT theory, so the only thing you have to worry about is..nothing! Bon voyage, and I hope you or your familiy don’t become a statistic.

    @Jerry I’m afraid you lost me @

    “The USA is under attack by an ideologically-driven enemy who cleverly exploits vulnerabilities in America’s free society to inflict national suffering and fear.”

    Are you talking about the GOP? Wall ST? Nuclear Industry? Military Industrial Complex? Greenpeace?

    The debate on body scanners seems far from over.
    ex: (must read comments, much interesting debate on both sides)

    re: Health Physics Society it seems, doing a quick search, is more a pr arm of the nuclear industry, so llogic dictates they would spin things in a favourable direction to them no?

    D6. Karl Z. Morgan, Father of Health Physics. For 29 years Dr. Morgan was the head of Health Physics at the Oak Ridge nuclear weapons laboratory. He helped set radiation exposure limits for workers who produced the first atomic bombs. He determined from his many studies that “there is no safe level of radiation.” This conclusion was not welcomed by those in the nuclear establishment who created the field of Health Physics to ensure that the health effects of atomic radiation would be documented and regulated by nuclear physicists rather than medical practitioners. In 1972 Dr. Morgan resigned so he could testify on behalf of those suffering from the adverse effects of atomic radiation. Atlanta, Georgia. 8 August 1983.

    1. Rational Debate

      I’m afraid you’re badly mistaken with regards to the Health Physics Society. It is the professional society for radiological safety experts (medical or industrial), and it’s board is responsible for professional certification. This is along the same lines as the National Society of Professional Engineers for, obviously, engineers, or the American Physical Society for physicists, or the American Chemical Society for chemists and so on. The HPS has never in any way been a ‘PR arm’ of the nuclear industry.

    2. Karl-Friedrich Lenz

      Your position is shared by Masayoshi Son of Softbank and is called the precautionary principle.

      That is a necessary way of thinking with the long-time cancer risk of handy phones recently highlighted by the WHO. It is impossible to know multi-decade effects since the technology has not been around for multiple decades.

      In contrast, radiation has been studied for over a hundred years. Even proponents of LNT don’t assert there is any proof for their hypothesis. All they can say that there is lack of proof against it (a position I don’t agree with).

      If after over 100 years of dealing with the issue there is still no proof, I for one won’t follow the negative theory because of the precautionary principle.

      I live in Tokyo as well. Last time I checked there was less radiation here than in Munich in Germany, my home town. No random cesium or iodine clouds on their way right now.

      As for your challenge, I would be perfectly willing to put a box of rocks with a lucky number of 77 mSv yearly radiation dose under my bed in a large-scale experiment to finally shut up the LNT doomsayers. That of course would need to be double-blind to exclude the nocebo effect which actually causes health damage, as explained by Mark Lynas in the article above.

    3. Zwitterion2


      The point here with respect to your 2 year old is that you are only worrying because you know ‘something happened’ and you believe you are suffering higher exposure than is normal. But what a lot of people dont realise is that many people in perfectly civilised parts of the western world were born, get on with their day to day lives and eventually die of normal causes in higher than average radiation areas – an awful lot higher than Tokyo which is particularly low (before and after fukushima).

      Take cornwall, which averages around 8 mSv / year (with obvious hot spots). The people living there are mostly unaware that they are living in an area about 4 times greater than London in radiation. Even if they have heard about a radon survey or such, few give it any thought. I have friends who live there so I know this is true.

      8mSv / year is much higher than Tokyo before or after fukushima, so the question you should ask yourself is would I be happy living in cornwall or any of the other higher background places? Or if I was in the UK would I be bothered by this and choose London to live in because I felt it was safer? Despite the pollution etc.

      A small part of fukushima is contaminated to a higher level than 8mSv / year, but most of the evacuation zone is lower than this according to the MEXT maps.

      I hope this adds something to what you already know. Since I own a scintillation counter and geiger counter, its quite easy for me to be relaxed about radiation, having ‘travelled with my counters’ to various parts of the country and world. Its given me perspective. I realise that if I had not done this I might still have the fear of radiation I had years ago and which I see in the majority of people nowadays, and I only hope that I might pass on a bit of my realisation that these low levels are not a concern. But if you still have difficulty I very much recommend purchasing some kind of radiation meter yourself.

    4. Global

      You might also want to look up the radiaiton exposure from flying (85,000 miles = the total annual dose of a nuclear power worker), and living in Denver Co. Oh, and eating a banana every day.

  13. Geoff Russell

    Great piece Mark. My understanding of the connection between a “single dose of 100 mSv” and “many years living with 100 mSv” is that there is excellent data on what happens with a single
    moderate dose, but only theories about the multiple dose or continuous dose scenarios. The difficulties of doing epidemiology with low doses are well explained here:

    Basically we will never know the impacts of low dose radiation because the effect is so small that it will get lost in the noise and we are unlikely to have good studies with enough people to measure these tiny impacts.

    On a practical note, my BNC piece a while back had pictures of what caesium radiation does to a human cell’s DNA and what milk protein does. Can anybody spot the difference? Has the lack of any difference stopped anybody drinking milk?

    1. peakoil2010

      Hi Geoff:

      you said

      “Basically we will never know the impacts of low dose radiation because the effect is so small ”

      Sorry, but this statement of yours is a contradiction in terms: “we will never know” and “because the effect is so small”… actually you DO know, the effect is small, and THEREFORE you know.
      I”m not playing with words, or using tricks, it’s in your own words, just read what you wrote… the answer to your and many other’s fears: exposure to low level radiation protracted or temporary, constitues demonstrably a much lower risk to our lives than many other daily activities, and most of all to alternatives, see below.

      I spend 10 hours a day, 5 days a week less than 1 km away from the biggest plutonium repository in Europe, and there are 19 so called “installations nucleaires de base”, nuclear reactors, fuel cycle facilities and research labs within the perimeter of the lab, and yet the biggest risk I take is driving to and from work every day…. as a matter of fact I have almost been killed twice by young ladies texting in their cars and not seeing me and my motorbike. The ~4000 permanent staff has a better-than-average health, and lives longer (no, I’m not pushing for a hormetic effect, just citing statistics…).

      To me, fear of radiation in the year 2011 a.D. is alike to fear of flying: a fobia driven by irrational fears, and as such I refuse it… then, of course, everyone is left with his/her own personal judgments and conclusions, but the rational mind cannot forget that the alternatives to nuclear power for the generation of electricity (gas, carbon and to a lower extent oil) have a much higher morbidity and mortality of nuclear, Mayak, Chernobyl and Fukushima accidents included.
      If you don’t want to believe my words, just take a pocket calculator, and do the math for Japan: 270 TWh/year (that’s what nuclear generated in 2010). Take the figures for natural gas (an average of 3 persons killed per TWh) and multiply by 40 or 50, the lifetime of a typical power plant. For coal it is almost 10 times as much, and this is only for OECD countries, if you factor China and India in then the numbers go up wildly.


  14. Rational Debate

    Interesting to note where you picked up that paragraph supposedly about Dr. Morgan – that single paragraph couldn’t be more disingenuous either. From the preface to Principles of Radiation Protection by K. Z. Morgan and J. E. Turner original edition 1967 reprint w/ corrections 1973, in the very first two sentences no less:

    …there was no organized professional effort for radiation protection until health physics had its beginning a the University of Chicago…This early group of heath physicists consisting of… K.Z. Morgan,…”

    This is why he’s often called the father of Health Physics, because he helped create the field, not some cabal in the nuclear industry who didn’t want those in the medical field involved – for that matter, one of the 8 listed in Morgan’s preface was a medical physicist no less.

    Furthermore, consider that he resigned from ORNL when he was about 65 years old, which I believe was mandatory at the time.

  15. Rational Debate

    Good article Mark!

    If you’ll allow, would like to suggest a revision to your statement “The scientific consensus is that, as stated by the ‘linear no threshold’ hypothesis, there is no safe dose for radiation” however. As stated, it’s not really correct.

    For decades the consensus of various national and international health physics and regulating bodies has been that at low doses (e.g., below about 10 R, although some use 25 R acute dose, or even higher exposures over longer timeframes), it is impossible to detect any effect one way or the other even in large populations because any effects, if they exist at all, get ‘lost in the noise.’ As a result, they have decided to use LNT as a conservatively safe calculated default assumption.

    In other words, the ‘consensus’ in no way rules out hormesis, nor does it rule in LNT – the concensus is not that LNT is accurate – it is that LNT is a calculated assumption based on the best evidence we have that at the very worst (from a public safety standpoint) is accurate, but at the best significantly overestimates any risk. That’s a vast difference.

    As to the Fukushima exclusion zone – I don’t think there’s any chance this would really happen, but it would be awfully interesting if the known facts of radiation effects were presented to former residents, and then they were allowed to choose for themselves if they wanted to move back or not.

    Also, Mark, have you run across any decent information about whether the highest dose rate areas are actually relatively small ‘hot spots’ or if they are more generalized contamination? As I’m sure you know, ‘hot spots’ are typically thought of as fairly small areas where for whatever reason, topography, sudden small cloudbursts washing out part of the plume, rain run off, wind, etc., wind up with significantly higher dose rates than most of the surrounding area.

    Hot spots can typically be decontaminated relatively easily and without huge cost, compared to more generalized areas with elevated dose rates throughout. It’s tremendously easier and cheaper to clean up a few square feet or even a few city blocks, than to have to deal with square miles…. I haven’t been able to find any good information along these lines, but have to suspect that at least some portion, if not much of the higher dose rate areas that are further from the plant are likely to be hot spots.

    1. Karl-Friedrich Lenz

      @Rational Debate

      You might want to look at the latest data published by Greenpeace. They have done some monitoring at schools. And they have found evidence for your theory, the radiation doses varying wildly at the same school complex. Hot spots are where much rain goes through.

    2. Mark

      LNT basically makes dose limits easy to specify and apply – that makes law easy to understand. It does not make it right, it makes it easy.

  16. Paul Cohen

    No Karl, it’s not a challenge to a double blind experiment (nice way to wriggle out it I though).

    It’s a “Yes I have the balls to stick by my convictions and I’ll willingly irradiate myself up >400 mSv/year Ramsar, Iran levels to prove it” request.

    or don’t you? In fact, they should make this a condition of membership in the Health Physics Society. I’d love to see the renewal numbers and the excuses after that.

    1. Karl-Friedrich Lenz

      @Paul Cohen

      Since I happen to think that 400 mSv per year is still about one third too low as a safety standard, agreeing with Wade Allison’s standard of 100 per month, I would have no problem whatsoever with your revised challenge.

      My answer is in no way meant to wriggle out, as you wrote. I only think that if one does this kind of thing there should be some kind of useful effect from the exercise. And finally getting rid of the evil LNT hypothesis by proving the point in yet another way would be extremely useful.

      Your “challenge” is rather questionable from an ethical point of view, though one hears it really often from the fear promotion crowd. I just blogged about a girl band video on youtube with a merry song about the dangerous dangers, and they have a line exactly like that in their text.

      If you think this is dangerous, or there is a chance it might be, why do you want me to go in that harm’s way? I think this is rather unfriendly, and it certainly does not help in convincing me. My “balls” or lack thereof are really irrelevant to the question of what radiation dose standard should be the rational choice.

  17. Paul Cohen

    @Zwitterion2 Please don’t patronise me with trite phrases like “you are only worrying because you know ‘something happened’ ”

    I explained I have done the research and I know what the numbers were before, during and current – as much as we can trust the various .gov and other organisations providing them, safecast included.

    Food chain contamination and associated monitoring is also an issue that remains unaddressed, or glossed over, by the majority in this thread.

    It’s not enough say with a little paternalistic pat on the head “It’ll be fine sonny, don’t you worry your little head about it – now run off to bed”.

    The Nuke Industry has engaged in an unplanned environmental pollution event. Real time monitoring of the environment and the food chain from producer to consumer needs to be implemented to an acceptable international standard as a first step in reassuring people that what they eat, breathe and drink is with acceptable limits (said limits still to be agreed on). We can argue till the cows come home about levels but if you don’t know what contaminants (chemical, biological and now – ty TEPCO – radiological) are in the food/drink products we buy (ESPECIALLY for children) then you are not even working from a solid base of risk management for society.

    1. Zwitterion2

      Paul, My aim was not to patronise – I can tell you have done your research already. But there seems to be a couple of holes in your understanding IMO.

      Tokyos background count is currently lower than most major cities so hopefully that provides some assurance that there is no current danger from an elevated background. I would take that further to point out that we dont consider for instance plymouth to be more dangerous to live in than London despite its higher background count. Even if the LNT is linear down to zero dose, the numbers are so small that it makes no sense to worry (about say a 1 in a million extra chance of getting cancer to someone who lives in a city and hence has a vastly higher chance of cancer from traffic fumes etc).

      With respect to food I can understand your concern more though. More maths are required to satisfy oneself that there is no threat from food, and of course a sensitive scintillation counter helps too.

      Two things are relevant here. One is the level of contamination normally present in food. You know of course about potassium 40, so you know that most food is somewhat radioactive, but you might not know that the radiation from caesium 137 is almost identical in form (balance of gamma and beta) but of a lower energy than that from natural potassium 40. Hence if you figure eating a banana with 15 bq of potassium is safe, then eating a bowl of rice with 15 bq of caesium is also safe.

      The other thing is that most of the significantly contaminated food became contaminated because they absorbed contaminated material from rain or mist on the leaves, and that this means that next years crops will not suffer this affect. This will mostly affect things like tea and salad for obvious reasons. If it was me yes I would avoid leafy veg grown close to the accident this year. That said, I can not really scientifically justify avoiding foods with a slight increase in radioactive contamination like the tea from south of Tokyo, because the increase in risk is so very small. But I might not feel comfortable drinking it so I admit, I might avoid it.

      The partitioning of caesium in plants has been studied in detail and its been shown that there can be a 1000 fold difference in the concentration of caesium between leaves and grain in crops such as rice. What this means is that concentrations of caesium in rice, wheat and other such grains is likely to be very low indeed. We can see that the first rice is starting to be harvested and is showing up to a maximum of 47 bq / kg, which once cooked will fall to 16 bq / kg because of the weight increase from the water. So if you take a normal serving of around 60 grams uncooked, you will eat around 2.8 bq of caesium per serving, or the equivalent of around a fifth of a banana. If you season the rice with lo-salt as I do (low sodium salt, high in potassium), if the rice absorbs a couple of grams of salt it will have an activity of 20 bq, almost 10 times higher than the activity from the caesium.

      Mineral water commonly contains up to 10 bq per liter of water and no one thinks anything of this.

      Your body fluids are relatively radioactive to the tune of around 60 bq / kg themselves, this is just the potassium 40 content. Further contributions from other elements like carbon 14 roughly double this number.

      Hope these numbers are of some interest to you.

  18. BlueRock

    A wonderful example of how someone with a simplistic grasp of a subject and an ideological obsession with it can pluck out a few peer reviewed papers and build a case that is wholly false.

    Internal emitters.

    That’s the only thing you need to read about to understand why the suggestion that a radioactive region around Fukushima is safer than central Tokyo is the ludicrously dangerous nonsense that it intuitively sounds.

    Why does Lynas think the Japanese have evacuated huge areas of their country? For fun?!

    The psychosis of the nuke cult gets more deranged by the day.


    * EPA: “There is no firm basis for setting a “safe” level of exposure above background for stochastic effects.”

    * NAS: “A preponderance of scientific evidence shows that even low doses of ionizing radiation, such as gamma rays and X-rays, are likely to pose some risk of adverse health effects….”

    * International Commission on Radiological Protection: “Overall, these animal tumor data tend to support a linear response at low doses and dose rates with no threshold.”

    * Very high mutation rate in offspring of Chernobyl accident liquidators. “These results indicate that low doses of radiation can induce multiple changes in human germline DNA.”

    The overwhelming scientific opinion is that there is no such thing as a “safe” increase in radiation over background and therefore:

    * “…cancer … risks are increased even with the smallest dose of radiation. The so-called permissible dose of radiation, for nuclear workers or for the public at large, represents only a legalized permit for the nuclear industry to commit random, premeditated murders upon the … population.”

    1. Zwitterion2

      I’ve heard this a lot recently but there really isent anything special about internal emitters.

      Whether the particle or gamma photon which creates ionisation in your body comes from an atom inside or outside you makes no difference. The fluids in your body which the radioactive atoms are dissolved in are fluids and hence mobile, so there is no repeated effect where a particular cell gets hit with more than its fair share of radioactivity. And if the total dose is the same, what difference do you think it makes where a particle or gamma photon starts its life? I would be interested to comment on your more detailed explanation of why you feel your statement above is correct.

      You know also that your body is fairly radioactive as it is, naturally? About 120 bq / kg of radioactivity?

    2. Mark

      Internal emitters ARE an issue – either by inhalation or ingestion. However, what is on the ground, in the air, in the food does not just leap into the body. There are a whole range of pathways and each of these, and the body’s own clearance, reduces the activity in the systemic system / organs etc. Like I said above (LNT is partly a simplification to make dose limits easy to apply), the media and industry quote external dose rates (etc) because they are relatively easy to understand. Try to start quoting Bq/g, Bq/m3, Sv Bq-1, – bio-kinetic pathways, clearance from the body, biological half-life etc and it turn into a blur for some.

    3. ColinG

      >”Internal emitters”

      There is an interesting postscript to this from the ICRP assessment of the lessons learned from Fukushima.

      The public and media are evidently under the mistaken impression that internal doses are more harmful than external doses. This perception is encouraged by anti-nuclear activists. But they are wrong.

      From the ICRP:

      “ICRP considers that for a given radiation dose the same radiation risk should be expected, whether irradiation is from outside or inside the body.”

      i.e. 1mSv of internal exposure carries exactly the same risk as 1mSv of external exposure.

  19. Will Boisvert

    Excellent post. People interested in this topic might like to look at an essay I’ve posted with a calculation of likely cancer risk for people living their life in the Fukushima exclusion zone. (It’s at It’s a long essay, so look for the section heading “How Bad is Fukushima?”)

    My model looks at a hypothetical person living 80 years in the 20-km Fukushima EZ. I estimate external radiation doses from outdoor radiation readings during the month of July, and assume most of that is coming from Cs-137 and Cs-134. In calculating lifetime radiation doses, I factor in radioactive decay, soil migration that removes fallout from effective contact with people, and the attenuation of the radiation dose that people receive while indoors, which is probably less than one fourth of what they receive outdoors. I also estimate internal radiation doses from Chernobyl data. In calculating the resulting cancer risks, I assume LNT and use the BEIR-VII risk factor.

    My conclusions:

    1) In the 10-20 km band of the EZ, lifetime cancer fatalities from the Fukushima radiation would be about 32 per 1000, a 3.2% absolute risk.

    2) In the 5-10 km band of the EZ, lifetime cancer fatalities from the Fukushima radiation would be about 50 per 1000, a 5% absolute risk.

    3) In the 2-5 km band of the EZ, lifetime cancer fatalities from the Fukushima radiation would be about 135 per 1000, a 13.5% absolute risk.

    These estimates are on the high side, using conservative assumptions and ignoring some radiation-abatement factors, like deliberate decontamination measures, that I don’t know how to model. And there are local hot and cool spots in the EZ where radiation is much higher than average (or less than Denver’s). But I think the numbers are still useful. They suggest that, in the most contaminated part of Fukushima prefecture, cancer risks from radiation are elevated but still substantially below those incurred from, say, smoking or auto accidents. So, Fukushima radiation is a significant local health problem, but not an apocalyptic one.

    1. ColinG

      Regarding how to model decontamination: it seems that even fairly low-tech DIY decontamination using a pressure washer can reduce the dose rate where people live by 70%-80%.

  20. Paul Cohen


    “If you think this is dangerous, or there is a chance it might be, why do you want me to go in that harm’s way? I think this is rather unfriendly, and it certainly does not help in convincing me. My “balls” or lack thereof are really irrelevant to the question of what radiation dose standard should be the rational choice.”

    The “>400 mSv/year Ramsar, Iran levels” is quoted in Jerry’s paper.
    Ramsar seems to get constantly quoted with whats seems to be some sort of hushed wonder tone and a “with no visible effect” to round off the argument that even high levels seem to have beneficial health effects.

    It’s not a matter of what I consider dangerous, and I am no stranger to real life controlled/uncontrolled risk – unlike most of you I can probably guarantee.

    It’s what you (et al – the extreme non-LNT.Rad Hormesis crowd) consider to be benign. You keep quoting figures, so why don’t you actually live by them?

    “Your “challenge” is rather questionable from an ethical point of view, though one hears it really often from the fear promotion crowd.”

    There is nothing ethically questionable about it. You are master of your own life and health. You have no problem wanting to force others to conform to your “standard” so, challenge/request/whatever, enough talking.

    Enough “Do as I say, not do as I do”. Just do it. Period.

    “Since I happen to think that 400 mSv per year is still about one third too low as a safety standard, agreeing with Wade Allison’s standard of 100 per month, I would have no problem whatsoever with your revised challenge.”

    Sounds like it’s no problem then. Line up kids. Time to eat your own lunch.
    Personally I would set the Ramsar figure of 400 as the limit as that seems to be the “OMG LOOK AT THEM THEY DON’T HAVE A PROBLEM AT ALL” figure, but if you want to go further – up to you.

    What’s that?

    No takers?

    Didn’t think so…

  21. Karl-Friedrich Lenz

    @Paul Cohen

    You add another ad hominem attack. Now I am not only a coward but also a hypocrite.

    As far as I am concerned, that ends any further conversation with you.

  22. Paul Cohen


    Read into it what you will, but don’t take it personally Karl.
    It applies equally to all of the “Do as I say not Do as I do” crowd.

    As it happens, the direct abuse I have received from Wade Allison “fans” in the past for daring to question his conclusions has been much much MUCH more direct and filthy. Even with my Aussie thick skin I was a little taken aback at the fervour of his fans. Interesting…

    1. quokka

      The purpose of this piece seems to be to milk the Fukushima accident for anti-nuclear political purposes rather than an attempt at an accurate and informative assessment of the situation. Wild claims of some further accident and in consequence “a meltdown will occur and all of northeastern Japan will be essentially finished” set the tone. Scary stuff eh?

      The author states that “Soil testing will help a lot” in determining which evacuees may return to their homes, but doesn’t even refer to the results of the extensive soil survey that have been published by the Ministry of Agriculture. Here is one of the soil contamination maps:

      The author purports to be some sort of expert, but is either ignorant of this data or sees fit not to comment on it.

      It is claimed that 9 becquerels per liter limit for seawater is “obviously too high”. As a decent sized banana has activity of more than 9 becquerels, this claim is not at all obvious to me. It then waffles on, speculating about bio accumulation and how far fish can swim. Recent testing off shore from Fukushima has shown no detectable contamination, but for some reason this is not mentioned either.

      It’s poor stuff that adds nothing and whose intent is to frighten people.

    2. Andy Dawson

      Re the “9 Bq/litre is obviously too much”.

      Always interesting to do a quick numerical sanity check.

      It’s often quoted that the average person has about 4400Bq of activity in their body at any given moment. Well, I’m on the large side (an ex prop-forward). I weigh about 95 kg – so, about half as much again as the average, and hence presumably, therefore have about 6600Bq in me.

      If I do a simple model, assuming I’m a cylinder of flesh of the same diameter I am at the waist I reckon I occupy about 125 litres. Some of that’s obviously empty space (lungs, windpipe, cranium) so knock that back to about 100 litres of actual flesh.

      That’s 66Bq/litre. So, obviously, I’m unnaceptably radioactive.

      Seriously, though that tells us something. Unless there’s evidence that the body selectively takes up caesium (something I’ve yet to see claimed) and retains it, drinking that water will not result in an increase in my body burden of radioactivity.

      Which rather negates “obviously unacceptable”, surely?

  23. Jess

    Thank you for this clear and straightforward post, and the largely well-reasoned comments. The cited references provide easy entry for further exploration. I have already found it a useful point of entry for acquaintances who are keenly interested once I raise the point of relative risk in discussions of nuclear energy, Fukushima, etc.
    Given the magnitude of the fear-factor, continually escalated by the MSM, many ‘environmentalists’ and the fossil fuel lobbies, otherwise well-informed people are often ignorant of these relative risk factors, and of the wide variation in background surface radiation levels, radon gas, etc. People seem equally unaware of the widespread distribution of radioactive particles from burning of coal (plus mercury, etc). Unaware, but fearful.
    The very fact that it has proven so difficult to gather statistically significant population-health risk factors (pro or con) for background radiation exposure in itself provides an upper limit to the actual risk.
    Anecdotally, I grew up in a uranium mining town with laughably weak standards compared with current practices. 50 years later all 5 brothers are fit & healthy entering retirement. If that’s the result of high background radiation, I’m all for it.

  24. Paul Cohen

    Here you go folks,a little more fear mongering from ..oh, hang on..the fear mongering is from Nuclear Industry itself?

    How can that be?

    1. TSkype group Japan Chat message, March 15/03/2011 3.15pm from @xxxxxx

    “I really hope all you guys get out of Tokyo and the surrounding areas as soon as you can.The captain of my social rugby team works for AREVA a French nuclear power consultancy.He is a conservative, leveal headed nuclear physicist. He says his company have evacuated their Tokyo office at lunctime and that radiation will inevitably reach Tokyo.He even predicted the 3rd blast which came today.”

    2. Former Japan PM: I thought nuke mishap could destroy Tokyo

    “At around 3 a.m. March 15, three days after the accident, I got a report from then Economy, Trade and Industry Minister Banri Kaieda that Tokyo Power Corp. was about to withdraw from the nuclear facility. So instantly I summoned the company`s president Masataka Shimizu and asked him to set up a joint countermeasures headquarters of the government and the company at the company’s headquarters,” Kan said.

    “Had Tokyo Power Corp. withdrawn from the nuclear power plant, nobody might live in Tokyo now.”

    Kan said, “If the power company had pulled out of the facility and left nuclear fuel unattended, the cooling water would have dried out within dozens of hours and the meltdown of reactors would have occurred,” adding, “If this had been the case, radioactive materials several or even dozens of times as much as those leaked in Chernobyl would had leaked. The country was brought to the brink of collapse.”

    Just lovely! Experts? If there is one thing we have learnt from the Global FInancial Crisis and #Fukushima it is that the word “Expert” is highly overrated and usually tied to some vested interest in the status quo.

    I’m still not getting any signups from the non-LNT/Radiation hormesis clergy to my “Ramsar Irradiation Invitational”.

    I don’t see the problem. I am proposing nothing that I would not call for from a vocal proponent of Fluoride in the water supply, vaccination, GM Food, MSG additive in the food, etc …. or even on the other side Organically farmed food. Do you actually “eat your own lunch” or are you just a paper tiger proposing something for others that you have no intention of risking life and limb for?

    The first people to demonstrate safety and efficacy of said substances should be the most vocal proponents for them. If you really want to maintain some form of crediibility and respect from the people you are selling the idea to you should “Do as you say”.

    1. Jess

      As noted in my post, I have done it, albeit inadvertently – but it was a wasted exercise because, as noted by others, the point is to learn something from the exercise. Without a controlled, widespread experiment there’s no knowledge gained.

      If we won’t learn anything from it, it becomes simply a childish dare – just like ‘how high can you go on the swings’ when you were in kindergarten. Why do you expect intelligent adults to respond to such a childish taunt?

      I’m sure that we could get volunteers for a statistically significant test if we were to simply set it up properly, double-blind, etc. with people in seniors residences.

    2. G.R.L. Cowan

      I’m sure that we could get volunteers for a statistically significant test if we were to simply set it up properly, double-blind, etc. with people in seniors residences.

      Or even better, we could have a huge industry that routinely and without fuss gives people of all ages, and all states of health, radiation doses roughly equal to what people just outside the FD1 evacuation zone experience if they spend a normal amount of time indoors.

      The study wouldn’t need to be blind, exactly; rather, radiation exposure would be called by other names — X-rays, thyroid scans, CT scans — and the dose recipients, and often those who administer them, would not even think of them as Fukushima-level individual doses that are multiplied by, not just tens of thousands of individuals, but many tens of millions.

    3. Paul Cohen

      “Anecdotally, I grew up in a uranium mining town with laughably weak standards compared with current practices. 50 years later all 5 brothers are fit & healthy entering retirement. If that’s the result of high background radiation, I’m all for it.”

      That’s your research? No data, just your assertion that you grew up in a high background radiation zone? WITH NO VERIFICATION OF ANYTHING? It’s worthless even as an anecdote.

      “I’m sure that we could get volunteers for a statistically significant test if we were to simply set it up properly, double-blind, etc. with people in seniors residences.”

      And furthermore, that has to be the most disingenuous research proposal ever. People in senior’s residences? You know full well the people MOST at risk from sustained low dose exposure – by whatever vector – are children and pregnant women due to rate of cell division,among other factors.

    4. Jess

      As I stated – it is an anecdote, not research!
      That’s the whole point – it is a childish dare to try things without any chance to learn anything from the experience. Give me a break

  25. Paul Cohen

    “If we won’t learn anything from it, it becomes simply a childish dare – just like ‘how high can you go on the swings’ when you were in kindergarten. Why do you expect intelligent adults to respond to such a childish taunt? ”

    On the contrary, as I pointed out it is no different from “I am proposing nothing that I would not call for from a vocal proponent of Fluoride in the water supply, vaccination, GM Food, MSG additive in the food, etc …. or even on the other side Organically farmed food.”

    One moment it’s all “it’s likely to be fine under x amount so we should go ahead and set that limit for the general population” then as soon as your challenged to “Practise what you preach” it’s suddenly “Without a controlled, widespread experiment there’s no knowledge gained.” and a childish dare?

    ps: Lets be open and talk about the Elephant in the Room – the real reason for setting higher limits. LNT acts as a huge operational, regulatory, and financial friction on the Nuke Indsutry, though that has not stopped sloppy regulatory regimes like Japan from flaunting them time and time again.

    1. Zwitterion2

      Paul, the LNT model is not and has never been fact – its not even a hypothesis really. But I am sure you know this since you sound pretty well read. You know as well as the ‘pro nukers’ on here that the LNT was a default model we had to adopt in the absence of better information. But does it make any sense?

      Take the following hypothesis. Sticking a million needles into a person within a few hours is likely to kill them, because of the massive haemorrhaging that would result. Continually sticking 100 needles into a person every day for the rest of their lives is likely to create skin changes and thickening which results in an increased chance of cancer at that site.

      However if you stick a couple of needles into a person a day and vary the site of injection from day to day, no scar tissue will build up implying no increase in the chances of cancer. Why is this? Because the body is a dynamic organism and has mechanisms to deal with what is considered everyday wear and tear.

      Radiation trauma to cells is very similar to trauma created by other factors like needles. You might quibble with that but what do you think is happening when you stick that needle into skin? Cells are disrupted and very occasionally one of those disruptions might be the severance of a DNA strand in a position where it might lead to a cancer given the right environment. Probably more common though is the resulting changes in skin (scar tissue) which is tissue which is more likely to turn cancerous – why, I dont know, my field is not biology. But this is the case.

      Why then do we imagine that trauma from radiation is any different to trauma from all of the other sources of cell injury in our world? Radiation is singled out and a nonsensical model applied to it, in the name of caution. But really, an overhaul of the LNT is long overdue not because of the nuke industry but because it seems to most scientists way out there on the left in terms of logical reasoning.

    2. Paul Cohen

      @Zwitteron Fine.It’s nonsensical, it’s due for an overhaul.
      Lets see some skin in the game. Enough with the excuses already.

  26. Barry Woods

    Good article by BBC’s Richard Black about why we have the reactor designs we have now.

  27. ColinG

    Interesting comparison of the size of the fallout pattern from Fukushima compared to the much larger land area contaminated by Chernobyl. (Google Earth is used to overlay the two, but even without Google Earth the article has a useful scale map of the two areas).

  28. Paul Cohen

    Overall Japanese health dangers are getting short shrift. “The last six months have shown a continued pattern of secrecy, cover-up, and minimization …. (The) news media and some so-called authorities have repeated the false information that doses under 100 mSv (millisieverts) have no health effects. All radiation doses have some effect, particularly when large populations are exposed. The Japanese government’s decision to increase the maximum allowed dose for citizens of Fukushima (including children) from 1 mSv per year to 20 mSv, the equivalent of 200 chest x-rays or the maximum many countries allow for nuclear workers … is unacceptable and remains in place despite vehement public and international pressure.” — Dr. Andrew Kanter

    In particular, the impact on the health of Japanese children is being glossed over. “Children are at least three-to-four times more susceptible to radiation than are adults. There are about 350,000 children under 18 in Fukushima Prefecture. If each of these children were exposed to the 20 mSv maximum over two consecutive years, the National Academy of Sciences BEIR VII report would predict 2,500 additional cancer deaths… The upshot is that there is no safe dose of radiation and exposing non-consenting people, especially children, to these increased health risks is medically unacceptable. The Japanese government is not adequately monitoring radiation contamination of soil, food, water, and air and is not providing the parents with sufficient information to protect their children.” — Dr. Andrew Kanter

    *Awaits predicatable reply accusing Dr Kanter of fear mongering*

    *Wondering when people will actually practise what they preach and lead by example (or is that too risky?)*

  29. Webcraft

    I really don’t understand the whole thrust of this argument.

    Firstly, the Japanese citizens affected are unlikely to be given the opportunity to make up their own minds on this – and if they were then God help them is they have to rely on debates of the standard displayed in this tcomment thread.

    Secondly, I can only asume that Mark’s underlying message is that we should not be so scared of radiation. Well, that may be so, but discussions like this that show profound uncertainties and disagreements are unlikely to be reassuring to the general public.

    Thirdly, whatever the statistical ‘truth’ I would hate to see this sort of discussion to be seen as a reason for relaxing nuclear safety standards, and I can’t believe anyone else wants this either.

    Mark’s current obsession with nuclear power is a red herring . . . until climate change denial is stopped in its tracks and effective lobbying put in place to force governments to seriously chase emissions targets the HOW is largely irrelevant. We need the will before we continue to agonise over the way.

    1. ColinG

      The thrust of the argument is that we should be realistic about the radiation risk in comparison to the trauma of evacuation.

      Large areas of the 20km zone have been evacuated not because the contamination is intolerably high but as a precaution against the risk of another incident at the plant. Two of the melted reactors have reached cold shutdown, and as the stability of the plant improves it is likely that many of the evacuees will be offered the option of re-occupying their homes. So they need to be able to make an informed decision.

      There are uncertainties over the risk from the radiation but the uncertainty is whether the risk is very small (according to LNT) or non-existent (for those who believe in a safe threshold for chronic radiation exposure). Regardless of the radiation model used, in many cases the radiation risk will be insignificant compared to the stress of not being allowed to return home.

      Certainly the experience from Chernobyl is that stress-related conditions have caused health impacts that have shortened life-expectancy regardless of radiation exposure; whereas there is little indication that increased public radiation exposure has had much impact on mortality (apart from some thyroid cancers due to early exposure I-131 which was gone in matter of months).

      As for “relaxing nuclear safety standards”: if the “safety standard” demands evacuation when evacuation is more harmful than staying-put then this is no longer a “safety standard”; it is a hazard.

    2. Paul Cohen

      Actually the core issue is reliable, transparent monitoring of the environment and food chain, as without these you cannot realistically assess any risks at all – whatever your position on radiation levels.

      As we have seen from #Fukushima and other crisis (non-nuclear, the latest being post 9/11 WTC site contamination cover up) you cannot fully trust either .gov or .biz to provide reliable data. You need a variety of independant monitoring sources to “keep them honest”. (ie: such as are attempting to do in Japan atm)

      re: Certainly the experience from Chernobyl is that stress-related conditions have caused health impacts that have shortened life-expectancy regardless of radiation exposure; whereas there is little indication that increased public radiation exposure has had much impact on mortality (apart from some thyroid cancers due to early exposure I-131 which was gone in matter of months).

      Certainly stress is a factor in all disaster situations, but there seems to be more than enough dispute of chernobyl radiation related death/injury that the above statement would have to be classed as “extremely disingenuous”.

    3. ColinG

      Not disingenuous at all.

      The dispute over the Chernobyl death toll is mostly related to how far any particular study wants to extend the geographical region to apply LNT to ever larger populations at ever lower risks over ever longer periods. But in every case the individual risk is low.

      The most exposed civillians received a few hundred mSv which presents a mortality risk of about 1-2% accroding to LNT. People further afield would have been exposed to proportionately lower risk (or no risk if you believe in a threshold).

      But the point is that even with LNT the predicted risk even from the highest doses is well below the level where any statistically obervable impact will be perceptible. The observation (or in fact lack of observed dose-related effects) just confirms this.

      The individual risk to members of the public from radiation was imperceptibly low across the board. There is no dispute about this. It is just some studies extend that diminishing imperceptible risk to huge populations to generate larger death tolls.

      On the other hand the physical and psychological impacts of stress and associated responses (depression, alchoholism, smoking etc) have had a statistically significant impact on mortality irrespective of radiation dose. That is the main impact of the disaster.

      And this is not just the normal stress from “any” disaster. It is elevated long-term stress because of an exaggerated fear of radiation. (As the WHO says, and as Mark spells out in the article).

    4. Paul Cohen

      “It is just some studies extend that diminishing imperceptible risk to huge populations to generate larger death tolls.”

      As opposed to some studies shrink that risk to small populations so as to generate smaller death tolls?


      “On the other hand the physical and psychological impacts of stress and associated responses (depression, alchoholism, smoking etc) have had a statistically significant impact on mortality irrespective of radiation dose. That is the main impact of the disaster.”

      You forgot to mention the slight matter of a 9+ quake and mega tsunami prior to Fukushima.

    5. ColinG

      Paul, actually I was referring to Chernobyl. But even with Chernobyl there is the major confounding factor of the collapse of the Soviet Union which makes it difficult to assess how much of the ill health is related to concern over Chernobyl and how much is related to general societal upheaval.

      However what can be said, and what has been observed, is that the level of poor health did not vary with radiation dose (with the notable exception of thyroid exposure). Therefore it is unlikely to be directly related to radiation.

      The general level of poor health in the Soviet Union dwarfed the small radiation mortality risk predicted by LNT. The direct health impact from the radiation, if there is any, is lost in the noise. This is fertile ground for controversy because everybody basically agrees that even using the LNT the projected mortality rate will be too small to observe empirically.

      The radiation doses were too small to have a noticable effect on the population. The public did not receive Sievert doses which would be necessary to create a readily observable impact on health (i.e. an effect that could be spotted by epidemiology). Thererfore the argument revolves around how large the imperceptible impact was.

      But the crux of the matter is that the individual risk from the radiation was low for the public (1-2% according to LNT even for the population closest to the plant, or those returning to the exclusion zone).

    6. quokka

      As I understand it, the UK already has quite ambitious emissions target of 50% reduction by 2027. Critical discussion of energy options is not just relevant but essential.

      There is no better fodder for deniers than half baked energy plans. If the penny hasn’t dropped yet, it should. Fear of lack of viable alternate energy options to fossil fuels underpins some climate denialism rather than well thought out objections to climate science.

  30. Mark

    If you are in the UK you can see the following programme on the BBC:

    “Fukushima: Is Nuclear Power Safe?” – the programme is a little simplistic (but that is no bad thing).


  31. Rod

    Hi Mark

    Have read this book by the New York Academy of Sciences? It claims that over a million people died from Chernobyl. Quite a wide difference from the handful that you claim.

    Chernobyl Radiation Killed Nearly One Million People

    I would be curious to have your take on it.



    1. ColinG

      The book was not written by the New York Academy of Sciences, it was merely published by them. They do not stand by the content and have no plans to re-print it.

      In fact they have a disclaimer on their web page:

      And they include a review which is extremely critical of the content and methods used in the book:

      The review explains the many flaws in the book.

      It is a rather damning indictment that the publishers themselves should reference such a critical review.

    2. John Wheeler

      That book is highly controversial, and the source of a lot of anti-nuclear hysteria.

      I’d be careful of stating that it’s “by the New York Academy of Sciences”, as even they pretty much stated that it’s not been peer reviewed by anyone and published “as is”.
      Doubt they really enjoy being linked to it at the moment.

    3. Mark Lynas (Post author)

      Rod – I’d be very cautious about using that book. As stated, it is not ‘by the NYAS’, but was merely translated, and in very controversial circumstances. This post has some interesting stuff about it – including the fact it was apparently initiated/helped along by Greenpeace International, and seems to fly in the face of basic scientific principles of epidemiology as well as radiology.

  32. andy

    Tell you what – put your money where your mouth is and live in a contaminated area yourself.

    1. Andy Dawson

      So far this year, I’ve visited Kerala (including spending a couple of days at a “black sand” – i.e. Monazite – beach) – general background in Kerala is about the same as the evacuation threshold for Fukushima; I’ve taken my family to the Lake District, in the area directly affected by the Windscale fire. And I’ve sent my eight year old daughter to stay with friends in Cornwall, where backgound radiation is about the same as that in Pripyat, in the Chernobyl exclusion zone. While there’ they spent time up on Dartmoor, where background can run up to eight times higher yet. And I fly back and forth to India three or four times a year, when I’ll get as much radiation per flight as all of those put together.

      I’ve lived for 12 months abutting Morecambe Bay – down-current of Sellafield.

      And not lost a moment’s sleep about any of them.

      Will that do for you?

      The real irony is, I also lived for three years downwind of Drax coal-fired power station – and will have recieved far more radiation from that than from all of those activities put together. So, let’s keep the hysteria to a minimum.

  33. Paul Cohen

    Have you read Climate change, nuclear power, and the adaptation–mitigation dilemma ?

    They conclude “Achieving the desired level of safety, and minimising the impact to climate change adaptation will likely be too expensive at many locations. Therefore, according to the criteria outlined here, nuclear power is not and will not be a suitable mitigation measure.” which seems a little more measured than your upbeat “she’ll be right mate, radiation is bonza!” analysis.

    1. ColinG

      Paul “I am neither pro or anti-nuke” Cohen

      Can’t you see that the conclusion does not follow from the evidence in the paper?

      They make no attempt to quantify the cost, nor to compare it with other climate mitigation technologies, so how can they say that “adaptation will likely be too expensive at many locations” and that nuclear power is not a “suitable” mitigation measure?

      The same paper could equally have had a pro-nuclear conclusion that nuclear plants are uniquely capable of withstanding extreme events due to their defense-in-depth approach to safety; and the low cost of the electricity leaves plenty of funding for any necessary adaptation.

    2. Paul Cohen

      “and the low cost of the electricity leaves plenty of funding for any necessary adaptation.”

      Uh, you might want to recheck your facts on that. Recent studies in Japan indicate (if I recall correctly off the top of my head) that Nuke, when all factors are taken into account including total accident costs, is double or more costs of existing energy solutions.

      re: Paul “I am neither pro or anti-nuke” Cohen

      lol. I guess that’s supposed to mean I’m anti-nuke? Nice try, but no cigar.
      Real risk analysis means looking at all factors, not just the ones you choose too. Unfortunately pro-nukers are as bad in this regard as rabid anti-nukers. I’m just pointing out some things you fail to bring up, which immediatly makes me suspicious of any of your arguments. Try presenting all the facts and balanced analysis of them.

    3. ColinG

      The news I read said that the cost of nuclear power in Japan had been revised upwards, but even after absorbing the cost of the Fukushima accident it was still cheaper than fossil fuel:

      Worldwide, there is general agreement between governments, the IEA, and the electricity industry that nuclear power is cheap per energy-unit cost even after incorporating waste liabilities etc.

      The current reference for the UK is probably the study commissioned by DECC:

      (Costs are summarised in the tables in Appendix B)

      The only studies that I have seen showing nuclear to be unusually expensive are by anti-nuclear groups. But if you have a link please post it.

      Even governments which are overtly phasing-out nuclear power, such as Germany, are not saying that they are doing it because it is too expensive. (In fact Germany will be paying tens of billions of Euros extra for the luxury of phasing-out nuclear.)

      “lol. I guess that’s supposed to mean I’m anti-nuke?”

      I was just pointing out that for somebody who says they are neutral on the matter you seem to have a gift for only seeing the anti-nuclear side.

    4. Paul Cohen

      further re: “and the low cost of the electricity leaves plenty of funding for any necessary adaptation.”

      Well, we KNOW that won’t happen, even if it was true.

      “The collusive ties between government and industry were what undermined nuclear safety regulations.”

      Nuclear is a useful technology, but much too twitchy and potentially dangerous given the large scale consequences of accidents to be allowed to be operated by an industry which is motivated by profit first and safety fast. I’m sure there are other ways and means of operating NPP to the benefit of society while minimising the risks. uh oh, I can hear the groaning from the nuke industry lobby already…

    5. ColinG

      “an industry which is motivated by profit first and safety last.”

      It doesn’t really stand up to scrutiny. Obviously the industry stands to lose a lot if there is a major accident; which is why there have been very few major accidents, ever. Safety and profit go hand-in-hand.

      Causing nuclear accidents is not in the corprorate interest of either the government or the industry.

      In hindsight Tepco would have happily forked-out for a higher sea wall and watertight generators in order to avoid the accident. Notably, the other affected powerstations evidently had adequate tsunami defenses – so the failure of regulation it was plant-specific not industry-wide.

      And post-fukushima the entire industry across the world has reviewed their flood defenses.

      So adaptation will certainly happen, as it always has.

    6. Paul Cohen

      “I was just pointing out that for somebody who says they are neutral on the matter you seem to have a gift for only seeing the anti-nuclear side.”

      Given the pattern of deception and corruption that seems to be a nuke industry trademark it’s an unfortunate fact that you have to fact check pretty much everything that they say, more so than the opposition. Why? Because they are running the reactors and *supposedly* controlling the risks, not the anti-nuke opposition.

      “In hindsight Tepco would have happily forked-out for a higher sea wall and watertight generators in order to avoid the accident.”

      You just jumped the shark with that one. To return the favour, you most definately seem to have a gift for only seeing the nuclear side.

    7. Andy Dawson

      Paul Cohen,

      Wait a moment,….

      operating practice for nuclear reactors in Japan had them coming off-line for inspection about every 12 months. Elsewhere, LWRs are run up to 18-24 months – for example, Sizewell B has repeatedly operated for around 520 days in a single run at full power.

      This gives you a comparison – you’ll see US reactors typically ran longer, (18 months compared to 11.5) and the shutdowns are less frequent and shorter (44 days compared to 98).

      Now, had Japanese operators been motivated to drive plant hard, they’d have been lobbying to be permitted to run US style operating practice.

      In practice, it didn’t matter – because the Japanese don’t run a competitive electricity market, even at the wholesale end- operators are allowed to pass through operating and capital costs plus a mark-up. There was no particular point in trying to trim down capital spend, or up operating eficiency, because the costs were passed straight through to end-customers.

      In fact, certainly as far as capital spend is concerned, I’d expect tpo see the opposite. Usually, regulated price models like this include a permitted rate of return on capital – which means that any extra capital spending is actually to the company’s advantage in terms of profit, as the rate is set aabove the borrowing cost- for example, OFWAT normally trims at least 25% of the proposed capital programmes of UK water firms for just that reason.

      There’s collusion, I’m sure – but it’s not about pushing plant unduly hard, or trimming spending – it’s more to do with making life easy for both bureaucrats and operators.

  34. Paul Cohen

    P6 “For instance heat waves could impact coastal locations, and
    hurricanes impact sites located many miles inland.”

    As I type this #fukushima is getting whacked by TY 1115 (ROKE) after having torn its way through Nagoya and Tokyo.

    1. ColinG

      “Deadly typhoon leaves Japan; nuclear plant intact”

      (The fact that all the other nuclear plants also weathered the storm, goes without saying.)

    2. Paul Cohen

      I guess you missed the live video of the crane toppling over?

      “selective memory”

    3. Andy Dawson

      You’re not about to claim that had radiological significance?

  35. MDN

    Does anyone know if the radiation hazard in the exclusion zone is ubiquitous (by this I mean you would be exposed to it pretty much whatever you do), or is it reasonably proximate such that if you took some reasonable precautions you could significantly bound or limit your exposure (for instance by gardening with a surgical mask on which Japanese are culturally familiar with as a flu prevention measure)??? If it is the latter I think that is an important factor to consider.

    1. Paul Cohen

      It would depend where you are ex: and what protocols, protective equipment, and decontamination procedures you follow.

    2. ColinG

      As I understand it, most of the contamination has settled onto the ground and other surfaces rather than being suspended in the air. So your main measures for reducing exposure involve decontaminating the surface of the areas where you spend most time.

      This might be as basic as using a pressure washer to clear roofs and gutters, reducing exposure by 70-80% e.g.

      The mask is presumably to avoid inhaling/ingesting material that may be re-suspended in the air.

  36. Randy

    Here in Vermont we have Vermont Yankee. This reactor has had so many problems and the owners keep lying and trying to cover up leaks and near-misses, that it is a wonder it is still in operation.
    Odd how the news reports just vanish and the public’s attention is turned to other issues like Britney Spears and Michelle Obama’s shopping trip.


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