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9 Comments

  1. Nice collection here. I hope that my comment shows up before Bob Applebaum’s first, as I expect he’ll show up shortly. He did seem to disappear from the comment string under Mr. Rockwell’s “Black Swan” post, particularly in not responding to my mention of his omission of any discussion of DNA repair mechanisms in all of his supremely confident assertions about his knowledge, intertwined with his accusations of an existence of a hormesis cult.

  2. “Attributing a death toll to Fukushima is thus simply a statistical exercise in mathematics and modeling that has no physical meaning and will not result in any attributable body counts.”

    That’s the bottom line. Clearly any attempt to do a meaningful risk analysis over radiation released by the Fukushima incident is a practical impossibility that only gets worse as the distance from the event grows. Any reasonably educated person with a basic grounding in science can see this. Consequently the only reason that these ‘studies’ are being floated is to produce antinuclear propaganda to frighten the ignorant. It is telling that the authors of these papers are not considered experts in the field. I suspect that anyone who is would not risk damaging their careers getting involved in such a farce.

    1. However the WHO has announced it plans to release one in 2013, after it has had enough time to carefully weight all the inputs and how this can be calculated.

      The outcome of how this will presented by the antinuclear crowd is of course is 100% predictable : “The WHO needed an inordinate amount of time to produce this rapport because it first had to silence and coerce all the involved physicians into producing a number that would satisfy the nuclear industry” 🙁

  3. Rod – thanks for this post. The question that jumps into my mind is how did this paper get past the journal’s referees and into print? Coupled with the appalling 250 words for a “summary of the controversy” – that seems to me a dereliction of duty on the part of the journal. Especially when it’s certain that the paper will become a standard part of a reporter’s “research kit” for mindless quoting when faced with a deadline.

  4. In safety assessment of geological repositories it is not unusual to apply assumptions that are known to be incorrect since they over-predict radiological consequences in a “conservative” fashion. This is because many important parameters in complex natural systems are almost impossible to measure directly or accurately, and in some cases it is not even clear that what is being measured is actually representative of what you think it is. There is therefore much discussion concerning what is, and what is not, conservative in safety assessment calculations. It also might be added that knowingly applying false assumptions in this manner, while perfectly acceptable in engineering risk methodology is not strictly scientific. Actually, a famous chemist and co-discoverer of Medelevium put this more bluntly in a 2003 paper stating that “conservative values based on incorrect models are not conservative, they are incorrect”. While I’m not competent to comment on the epidemiological calculations in the paper, my understanding is that the LNT model falls squarely into the category of conservative assumptions. The key is to understand the impact of those assumptions and to be able to argue a safety case in a cogent and rational fashion given that over-conservatism can skew risk indicators, which if taken to absurd levels can result in poor engineering choices or policy decisions.

    In a recent safety assessment of a proposed deep geological repository for spent nuclear fuel in Sweden, dose calculations were made of naturally occurring radionuclides in groundwater at the site following the same methodology as the compliance case study (http://bit.ly/LPdVnz, pp. 124-125). Sweden has a granite dominated geology, so uranium occurs naturally at an activity level of about 50 Bq/kg of rock. Even with some reasonably conservative assumptions, the mean effective dose rate from naturally occurring uranium series isotopes (i.e. U238, U234, Ra226) was estimated to be roughly 40uSv/y in groundwater discharge to streams and water courses. This is about 200 times the level estimated for the peak anthropogenic dose (sum of all radionuclides) in the regulatory compliance case for a one million year period. Radon was not directly included in the calculations since being a gas it could be reasonably assumed to dissipate from surface water relatively quickly (although drinking water sourced from wells drilled in granitic rock should probably be well-aerated before drinking on a regular basis). If it were to be included, the Rn222 activity in the discharged groundwater would be about 85 times higher than the next most important radionuclide Ra226. An important caveat is that this is not an average dose to a population, but to “a representative individual in the population that is exposed to the greatest risk”. These calculations were not made to be able to say that the anthropogenic impact can be arbitrarily discounted (assumptions can always be questioned), but merely to provide a context for the risk metrics implied by the safety assessment methodology.

    It is interesting to note that the time series data shown in Figure 4 in the Hoeve & Jacobson paper for Cs137 ground activity (an approximately decaying pulse input) for Japan over the first month appear to be roughly 7-8 times greater (if I read the Figure correctly) than the expected amount of Ra226 activity discharged continuously from groundwater over the same period of time in a typical coastal landscape dominated by granitic geology. The peak for the US appears to be approximately in parity with this estimate (ca. 0.33 Bq/m2). I don’t think that the fact that levels of I131 and Cs137 activity being 3-8 orders of magnitude above the background level is particularly relevant since they do not occur naturally and the background levels are essentially residues from atmospheric nuclear testing in the 50’s and, of course, Chernobyl. In the Swedish study cited above, the landscape dose factor (Sv/Bq) for Ra226 was roughly 30 times higher than that for Cs137 (http://bit.ly/M9Esxr, Table 4-1, pp. 38), so on a directly comparable dose basis, the impact of the Cs137 should be even less than that of the naturally occurring uranium series isotopes.

  5. There’s increasing awareness of the observations consistent with radio-hormesis, now almost to the point at which someone who would attempt to pass themselves off as knowledgeable in the field of radiation health physics cannot easily get away with simply ignoring the phenomena. We should encourage and promote more work like that being done by Edward Calabrese at UMA and Jacquelyn Yanch at MIT and at WIPP in NM. This is potentially some of the most important biological research being done today. The DOE, NIH, CDC, & NAS should all be sponsoring additional research into this potentially revolutionary field at multiple research universities and national labs.

    Apart from that I don’t see this Jacobson paper serving as any big rallying cry from the usual suspects. As Richter pointed out, the upper bound of Jacobson’s worldwide Fukushima mortality figure is still an order of magnitude less than what the NAS pegged as the annual coal mortality toll in the US just a couple years ago. Perhaps the big take away should be than even using LNT models fission remains remarkably safe under the most extreme accident scenarios that are physically possible. The NRC should be pressed to justify and encouraged to continue to revise downward any “prompt” fatality projections from its PRAs.

    Back in the 70s the UCS released with great media fanfare their criticism of the (absurdly inflated) official risk estimates produced by the NRC. The late Bernard Cohen observed that even granting UCS’s own numbers the risk from nuclear energy was still substantially less than not only all fossil fuel alternatives but also less than from the electricity itself that would in any case have to be generated.

    1. @Aaron Rizzio

      I see no reason to concede any ground on this issue. Jacobson’s paper is just plain wrong and gives inaccurate numbers.

      The radiation released at Fukushima, described by professional antinuclear activists like Arnie Gundersen as worse than Chernobyl and by others as a catastrophic nuclear accident that will create dead zones that last virtually forever, did not kill anyone and should lead to very few isolated areas being declared off limits for human habitation. (Plants and animals will thrive because even there the radiation is not at levels that are actually hazardous.)

      I will grant that radiation, at levels that greatly exceed about 100 mSv/year, is dangerous and worthy of cautious handling. I grant that humans in a nuclear era need better training about how to use “time, distance and shielding” to protect themselves from hazardous doses. They do not, however, need to worry at all about the doses they receive from routing power plant operations – even at the reactor site itself – and they do not need to worry about the doses that they might receive from even the worst accident that has any probability of occurrence.

      The US NRC’s State of the Art Reactor Consequences study should be widely distributed and discussed. It puts the lie to the assertion that nuclear energy is a public safety hazard.

      http://www.nrc.gov/about-nrc/regulatory/research/soar.html

      Please do not get me wrong. I live and breathe reactor safety, but I am certain that we have implemented acceptable and reliable solutions to the major issues that produce any public risk.

  6. I’m quite sure the areas around Fukushima will be resettled far sooner than is currently envisioned. Evan at Chernobyl the natural habitat within the “exclusion zone” is far healthier than it was before the accident or the land outside the zone. It is not entirely inconceivable if radio-hormesis is validated by additional research that the new risk models would show net health benefits in the wake of (increasingly improbable) nuclear accidents, e.g. there will be ~30k fewer cancers within the fallout region and real estate values will go up!

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