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LNT is alive over here in Tokyo, where today’s Tokyo Newspaper runs a 2-page spread on Fukushima’s water releases…

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Another excellent post. This historical piece of Popperian theory-refutation is vivid.

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Thanks for this excellent post. Can you explain why you use an RBE of 16 for radium?

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Anton,

I assumed all the radium was Ra-226. 81% of the energy in the Ra-226 decay chain is alpha with a RBE of 20. The rest is beta and gamma with an RBE of 1. Close enough for rock and roll.

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On reflection, I screwed up. Ra-226 has a half-life of 1600 years. So we are nowhere near equilibrium in the decay chain. I should have used an RBE very close to 20. Fortunately, this error does not change the overall conclusions.

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While I agree 100% with your views on the LNT model, it is noteworthy that even that model values a life lost to radioactivity at least 100 times more than a life lost to air pollution (PM2.5 and PM10 particles).

This is based on consensus data on the mortality rates and the regulatory ‘safe’ levels.

I have never been able to find any justification for this.

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Just one more example, among thousands, of "Don't let the facts get in the way of your story". Our only way forward is to always ensure that our 'stories' agree with the facts. The other way around always leads to stagnation at best, and disaster at worst.

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Thank you for continuing to educate me (us) on the nature of radiation and biological corrections thereto. And for presenting the administrative and vested interest battlements over which the populace/ electorate/ public must climb over to achieve the benefits of nuclear power.

Truly frustrating that such science based logic and evidence cannot overcome fears and fantasies from its "progressive" not-really-in-favor-of-progress resistors.

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Are there other medical or biological impacts from low or high levels of radiation that should also be addressed? [Bombs aside, I suppose]. I just thought of the irony that we use radiation to kill cancer cells that some other source of radiation (just maybe) has initiated in the first place.

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The original concern was genetic damage which would propagate to future generations. That's where LNT originally came from. The idea was genetic damage was unrepairable. But this pretty much disappeared in the 1950's when the 10 year Neel study of 70,000 pregnancies of bomb survivors showed no damage to kids conceived after the bomb was dropped.

There have been sporadic attempts to link radiation to heart disease, etc but as far as I can tell nothing the least bit convincing, certainly not at the dose rates encountered by the public in a NPP release.

Of course, the fear of radiation and the stress of prolonged evacuation has caused all kinds of medical problems, mainly among evacuees.

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I have a question based on the following photograph of a truck driver with clear

difference in skin damage on the left and right side of face due, it is asserted, to sun damage.

https://www.cbsnews.com/news/trucker-accumulates-skin-damage-on-left-side-of-his-face-after-28-years-on-the-road/

In a discussion about LNT, this photograph was presented to me as evidence

that damage due to ultraviolet radiation IS cumulative.

The claim was that a truck driver had a low daily dose of UV radiation on his left side and

presumably a lower dose on his right side.

One supposes that this radiation dose was within the body's ability to repair itself and

was cumulative over many years.

The claim was that the observable difference is evidence of cumulative DNA damage.

I don't know the validity of this claim. But the person with whom I was talking stated

that skin cancer can equally well result from similar damage to the DNA, and this

was the reason that dermatologists recommend the daily use of sunblock.

I did not have a good response to this photograph.

The argument is that skin damage is cumulative and therefore, the probability of skin cancer is cumulative.

I believe many people would understand this photograph as a strong example of why ANY radiation is bad and should be minimized.

Perhaps you can assist me with blunting this argument.

Many thanks.

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Paul,

AFAIK neither LNT nor SNT bills itself as a model for skin aging, although this individual appears to have been extraordinarily sensitive to UV, probably the result of altered repair gene(s).

When it comes to cancer, you don't have to be an LNTer to accept the obvious fact that there is a cumulative effect. SNT among others claims there is a cumulative effect. The dial painters clearly exhibit a cumulative effect. No one I know denies there is a cumulative effect.

The question is what form does it take, and how well does your model describe that effect? LNT does a horrible job of modelling the dial painter data. SNT accumulates harm differently and does a far, far better job than LNT of modelling that cumulative effect in the dial painter data, but is still too conservative for the high end dial painters.

LNT in accumulating harm linearly effectively denies any repair which is nonsense. SNT posits a simple period by period repair process in accumulating harm. It is qualitatively more realistic than LNT. But the real repair process is more complicated. SNT misses that, and errs on the high side in very high dose rate for prolonged periods situations.

The idea that any non-LNT model denies that there is a cumulative effect is such an obvious fallacy, that it's hard to believe that the purveyors are unaware that they are making a bogus argument.

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