Biology first, then data.

The Green Table. Populations who have received very large doses. If a dose is received all at once, (top portion) we start to see significantly increased cancer at total doses much above 100 mSv. If the dose is received more or less evenly over a protracted period, (bottom portion), it does not appear to matter how large the total dose is as long as the dose rate is less than 20 mSv/day.

The Gordian Knot Group just might be getting some traction. At least, we are getting some pushback. Missionaries report that the latest tactic by the LNT shamans is to claim the Green Table is "unscientific", because it mixes High (alpha particle) LET exposure with Low (photon and electron) LET exposure.¹ In particular, we can disregard the radium dial painter and the Radiothor drinker data, because these people suffered mainly alpha exposure. In a nuclear power plant release, essentially all the exposure will be Low LET.

The Green Table does mix High and Low LET exposure, but it does so according to their model, not mine. I did not come up with an alpha particle RBE of 20.² They did. The Green Table meticulously follows the rules they have told us to follow. They are now denying their own model. What do they believe?

But this whole argument is bassackwards. Let's talk about "unscientific". Science starts with a theory, a postulate --- the speed of light is the same in all inertial frames of reference --- then we try to come up with a quantitative model that is consistent with that postulate, and then we check the model's predictions against experimental data.

BREAK FOR COMMERCIAL

One of the things I like about the How to make nuclear cheap again book is it gets this order right. It outlines the biology before talking about radiation harm models. Despite this, the book has only sold about 60 copies. The charitable explanation is that the choir thinks the book is redundant, since it's just a distillation of the substack posts. This is misguided on two grounds:

1) There is real value in having the argument laid out in a concise, orderly manner rather than spread over 200 articles in a haphazard fashion.

2) The book is not aimed at the choir. It's aimed at your well meaning friend or relation who realizes we are in trouble and is searching for a way out, but is unaware of nuclear's promethean promise.

I want the choir to buy the book and then give it away.

RETURN TO NORMAL RANTING

That's the way LNT originated. LNT was proposed in the 1920's by geneticists who believed that damage to a gene was unrepairable. This was well before the discovery of DNA. They did not know what a gene was; but they were convinced it was unrepairable. LNT is a model that is consistent with that postulate.

We now know that LNT's foundational postulate is flat wrong. We now know that a gene is just a short piece of DNA that encodes a bit of genetic data. We now know that we have a remarkably effective system for repairing DNA damage. We know why this repair system can handle dose rates hundreds of times larger than average background. We even know quite a bit about how this repair system works. Our radiation harm model must be consistent with this indisputable biology. LNT is not, and that's why it is so fundamentally wrong.

It is not the use of the dial painter data as an example of how far off LNT's predictions can be that is "unscientific". What is "unscientific", to put it as politely as possible, is continuing to promote a model after its foundational premise has been proven to be false.

1. LET is short for Linear Energy Transfer. It's how much energy the particle releases per millimeter of path length in tissue. The LET of alpha particles is typically several hundred times larger than that of electrons and protons which have the same energy.

2. RBE is short for Relative Biological Effectiveness. It is based on the ratio of chromosome aberrations caused by the same amount of High and Low LET dose in grays (same energy absorbed per kg of tissue). Low LET damage is far more spread out than High LET. The tightly clumped High LET damage is much more likely to cause Double Strand Breaks (DSB), and worse two closely spaced DSB's, dubbed Double DSB's (DDSB). Double DSB's are the one type of DNA damage that are DNA repair system has a problem with. The repair system can end up rejoining the wrong ends which can result in a viable misrepair. Some of these mutations will escape our immune system, and some of those can develop into cancer.