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So if I had to summarize the hypothesis, it would be that a cell getting hit by a small dose of radiation will trigger a lot of cleaning routines that will mop up damage that normally accumulates.

A bit like if you have a house guest who walks thru with dirty shoes leaving footprints, you're not going to clean just the footprints but the whole floor, which probably had a lot of dirt evenly spread around anyway.

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Stay away from "dose". It's a very nasty four letter word. The theory is that the cell is hit with a very high rose rate for a very short time. Otherwise the radiation dose rate would be buried deep within the metabolic dose rate and the cell would have no way of knowing the difference.

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It seems to me you could demonstrate a health benefit by exposing animals like mice to slightly above normal levels of radiation spread over their lives.

I am somewhat skeptical as even “cleaning routines” likely come with some cost. More likely I suspect you won’t be able to detect anything at very low levels until you hit a harmful point.

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This has been done. The best animal for the experiment unfortuantely is a beagle. We "sacrificed" 7000 dogs in the 1950's and 1960's in various experiments. In one set of experiments, the dogs were exposed to differing steady photon dose rates for their entire lives.

The dogs with the highest dose rates died first even tho they had received the smallest cumulative dose at death. The experiment went down to 3 mSv/d above background. These dogs lived almost as long as the control group, but no hormetic response was detected. See Section 5.7 in the Flop book which you can download from https://gordianknotbook.com

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So not quite evidence to make the dentist not put that lead bib on you when you get X-rays.

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A set of 4 bite-wing Xrays totals about 0.005 mSv, almost all of which

is absorbed by the mouth and lower face. The only function of the lead bib is to improve the technician's bicep tone.

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The clearest evidence for hormesis that I have seen is Cohen's study on lung cancer rates vs radon levels. There is a clear and significant reduction in cancer rates for counties with higher average radon levels. The anti-nukers I have been debating HATE this study, and they come up with all kinds of speculative reasons why it is invalid. One even found a map of radon levels and suggested that there was a reverse correlation with smoking, IGNORING the fact that the study controlled for smoking and a lot of other potentially confounding factors. Unfortunately, both sides of the debate prefer to stay in their safe spaces, and not confront evidence contrary to their beliefs.

https://citizendium.org/wiki/File:Lung_Cancer_from_Radon.png

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Low dose rate radiation is an extremely weak carcinogen and an even weaker therapeutic When you are dealing with dose rates that are near or below background in parts of the planet, something else is always more important: smoking, pollution, wealth, altitude, life style, etc, etc

Low dose rate radiation is so weak a carcinogen, it is simply impossible to reliably correct for all these confounders. The signal to noise ratio is too small. If the net effect of the errors in correction is an increased cancer rate, the LNTers celebrate. If the net effect is a decrease, the hormetians claim victory. Nonsense. Both LNTers and hormetians give low dose rate radiation far more power than it has.

Cohen himself never said he had proved hormesis. He said his data disproved LNT. But the easy way to go after LNT is find populations which have received very large doses so you can actually see the effect of radiation. Then compare the cancer incidence of those populations who have received very large doses acutely and those that have received the same dose more or less evenly over protracted periods. LNT says the effect should be the same. This is the real test.

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We agree that LNT is bunk, easily dis-proven exactly as you say. The remaining question (hormesis) is not near as important to resolve. When I got outrage over our Fear of Radiation article from a radon remediation expert and a smart anti-nuker, I was ready to concede and delete the figure from Robert Hargraves, critical of EPA's policy on radon. Then after following Hargraves' links, and understanding the research, I decided to keep the figure and publish a summary of the debate.

Mike Conley has the best response to Cohen's critics. We still don't have a response to the European Code plot showing data that appears to contradict Cohen's study and support LNT for low exposure rates.

We can't just say there is too much uncertainty in the statistics. Cohen's scatterplot disproves that argument. We can't argue that there are confounding factors. Those are carefully accounted for in Cohen's study. One or the other plot has to be wrong. I suspect it is bad data in the European Code article, long believed but never carefully reviewed.

For now, I will the keep the debate on radon unresolved on our Debate page. It is not central to our article on Fear of Radiation.

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It seems you know more about Cohen's work than Cohen did. The scatter diagram that you keep referring to is after Cohen's attempt to control for the confounders. If that attempt is changed than you get an entirely different scatter plot. Cohen's problem was that he had to correct for not just smoking but perhaps a dozen other factors that were stronger than low dose rate radiation, and he ahd to get them all about right.

One of the reasons Cohen never claimed to have proven hormesis is the ecological fallacy. In using county wide averages, Cohen was assuming the response to the average input is the same as the average of the individual responses. Cohen acknowledged that he ahd no right to do this, but he pointed out that there was exactly one group that could not challenge him on these grounds. That was the LNTers because that's precisely the assumption LNT makes. So Cohen could claim he had disproven LNT, but he was smart enough to know he had not proven hormesis.

The reason I was so reluctant to talk about hormesis is as I knew some dunderhead was going to learn teh wrong lesson. Pls don't keep proving my concern was justified.

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Jack, I don't claim to know more about Cohen's work than an expert in health physics, or more about any topic than someone with expertise in that topic. What I can do is debunk bullshit with simple science. I have done that in much of my career, often fighting with statistics experts, once in Federal Court with a simple histogram. So in this debate over radon and lung cancer, I'm keeping an open mind, listening to both sides, and reading to understand as much as I can of the deep statistics. It looks to me like Cohen has adequately defended his study against the attacks of statistics experts. If you read his paper at http://www.phyast.pitt.edu/~blc/LNT-1995.PDF you can see that he dealt with the ecological fallacy, smoking prevalence, and other confounding factors.

None of this is necessary, however, if we can just assume there was no "cherry picking" or other fraud in the creation of the scatterplot linked above. It is just a simple plot of the raw county-level data showing a clear downward trend.

I know this is not the right forum for this discussion, so I will invite you to the ongoing debate at https://www.facebook.com/groups/2081763568746983/posts/3726936500896340/?comment_id=3728618867394770

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I had read that Cohen paper maybe a half dozen times. But I went back and read it again. As I had remembered, Cohen makes no claim that he has shown hormesis. He makes it quite clear that his defense against the ecological fallacy objection applies ONLY to LNTers. Cohen makes it quite clear that non-LNTers such as myself can challenge the paper on this basis.

If you look at a map of the high radon verses low radon counties in

the US you will immediately be struck by how well they match up with just about every political and sociological stereotype you can come up with. High radon is South Dakota. Low radon is New York City. Cohen struggled as best he could to correct for all the differences in life style, etc but unless low dose rate radiation is as powerful as the LNTers claim, he was faced with an impossible task.

There have been myriad papers on radon exposure. Some show benefit. Some show harm. None that I've seen convincingly support LNT. The problem is the effects of low dose radiation are so small that they are drowned out by other factors, which are ignored or downplayed in these studies.

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