To be clear - I'm calling the regulatory basis of the regulations fraud. It is fraudulent science and wildly inappropriate application of precautionary principles.
The Sievert is a stupid and useless unit. We must first measure the harm, which is not the same thing when we are talking about killing a person and generating small DNA damages which will cause cancer after ten years.
This pro-LNT folks are mostly arguing from authority and refusing to seriously look at the data. CZ policy is to allow each side to make their best argument, in their own words. We trust that our readers can make their own judgement as to the validity of the arguments.
This comment is off topic. The post never mentioned LNT. I'm going to let it stand, but further off topic plugs for citizendium will be expunged.
The whole discussion of radiation harm is totally bassackwards. We start by posing the issue as pro-LNT or anti-LNT, and then immediately turn to the data, almost always low dose data where the single to noise ratio is so low it is possible to wring any conclusion you want from it.
We should start with the biology, and then come up with a radiation harm model that is consistent with that biology. And to calibrate that model we should look at populations
where the signal to noise ratio is high enough, so we can reliably separate radiation from all the confounding factors.
Sorry, I should have said "people who vigorously defend harm from low levels of radiation". I made the leap to LNT, because that is the basis of their beliefs. I would love to see an article like you suggest, providing an alternative to Wikipedia's article on LNT. Bear in mind, an encyclopedia article must be neutral in tone and well sourced on every controversial fact. Advocates can have their say on the Debate page with each article.
The signal to noise ratio is very high for the Kerala study and for the radon studies. Perhaps we should move the noisy bomb survivor study to the bottom of the page.
My father was working at the Chalk River Labs in another building when the accident occurred, so he was involved with the cleanup. He died at age 89 in 2012. More famously Jimmy Carter was also involved at died at age 100.
Clearly 2 lives cruelly cut short by radiations /s
I recall dad mentioning that he went home in Deep River & measured the radioactivity on his clothes which he left on the porch of the house. The next morning he measured the radiation again and found near background. It was almost all very short lived isotopes.
I assume you are referring to the bottom line in the Green Table.
The NRX screw up was in 1952 when your father and his buddies had a vision of providing humanity with cheap electricity. Now we have a nuclear establishment whose overwhelming interest is self-preservation. Did he ever talk to you about that transition?
I don't recall mention of the transition you talk about.
In 1959 he left Chalk River & took the job of running the radioactivity standards lab at the National Research Council of Canada. So that was measuring the amount of radiation and wasn't directly involved in studying the health effects of radiation exposure.
The more I think about your order, the more I like it. It's logical. We spend far too much time bashing LNT when we should be talking about the basic biology after which LNT is clearly a non-starter.
When my wife applied for the Royal Canadian Mounted Police (RCMP) in 1996, she was moving along the process and in one day in the spring of 1996, as a part of this process, she received about 100 x-rays. They do this in the event an unfortunate situation arises, the police-person perishes and they need help assisting in identifying the body. She asked, "is this many x-rays in one day safe?" She was told "oh yeah, its fine, we've been doing this for years". She also had to get a few dental x-rays for this process and then later in the year, she broke her leg, which ended the hope of becoming an RCMP officer, and had to get a few more x-rays for this.
In Canada, the protection standard is 1msv/year (I assume above background radiation), but of course it varies all over the country.
So I assume occasional instances where SNT is exceeded, even by 5x or more, is OK? Thank you for your work, SNT seems far more rational and practical than LNT.
SNT embraces the No Threshold doctrine which takes away the pro-LNTer only defense. But it means that any amount of radiation involves some risk, however tiny. But for just about all the dose rate profiles encountered in normal life that risk is equivalent to a Lost Life Expectancy of seconds or less. Risks that most people would reasonably conclude are not worth worrying about.
We would need to put numbers on your wife's dose rate profile to come up with the SNT estimate of her increase in cancer incidence, which prediction will almost certainly be overly pessimistic, since SNT was designed to err on the high side.
Her profile was obviously pretty spikey. SNT claims that a spike of 10 mSv is much worse than 10 mSv spread over say a month.
But our repair processes operate on a time scale of a few hours. This tends to smooth out very short term spikes. For such processes, it does not make much difference whether she received two 5 mSv spikes 5 minutes apart or one 10 mSv spike.
SNT makes the heroic and pessimistic assumption that it makes no difference at all, as long as the dose is received on the same day. A dose that is spread over a day, is treated as if it were all lumped together in a spike received at the start of that day. All the xrays she received in a single day would be added together, kind of a micro-LNT.
How bad this approximation is can only be determined by looking at the data. The data such as the radium dial painters says SNT is awfully pessimitic, but, since SNT recognizes our ability to repair radiation damage, it is many orders of magnitude closer to reality than LNT. In my view, it is close enough for regulatory purposes. But it is possible to make the argument that it is not close enough. It's too pessimistic.
Do you know how much the radiation dose is for chemotherapy and radiation treatments? I found this, but I'm not familiar with the conversion from greys to sieverts. Perhaps there is a different article that provides a better explanation, but I couldn't find one. https://pmc.ncbi.nlm.nih.gov/articles/PMC2394476/
The conversion factor from grays to sieverts is 1.0 for photons and electrons.
20 for alpha particles. All external doses (eg xrays) are photons. Pills are being developed that will carry electrons and alpha particles to the tumor. But except for the latter, you can just treat grays and sieverts as interchangable, although only grays (J/kg) are actually measurable. Sieverts are an ad hoc kluge which probably shoudl be done away with. But we are stuck with them for now.
Radiotherapists need very large doses delivered over a very short time in a very localized manner to kill tumors. The dose rate, timing and localization is at least as important as the total dose. Xrays are usually delivered as a series of spikes (called fractions).
The idea is
1) normal cells recover more rapidly than cancerous,
2) fractionation allows tumor cells that were in a radio resistant phrase of the cell cycle
to cycle into a more sensitive phase
3) Hypoxic (more radioresistant) tumor cells can reoxygenate between fractions..
The specialists squabble among themselves about the relative importance of (1), (2) and (3). A typical fractionation schedule is one spike of 2 Gy per day to teh target, 5 days a week.
You now just about everything I know about radiotherapy.
If we ever do encounter a space-fairing species, it will be because they didn't fall for this fraud.
To be clear - I'm calling the regulatory basis of the regulations fraud. It is fraudulent science and wildly inappropriate application of precautionary principles.
The Sievert is a stupid and useless unit. We must first measure the harm, which is not the same thing when we are talking about killing a person and generating small DNA damages which will cause cancer after ten years.
https://danielcorcos.substack.com/p/on-the-biological-effects-of-radiation
And yet, there are intelligent and sincere people who vigorously defend LNT. See Citizendium's summary of the debate at:
https://citizendium.org/wiki/Fear_of_radiation/Debate_Guide#LNT_Controversy
This pro-LNT folks are mostly arguing from authority and refusing to seriously look at the data. CZ policy is to allow each side to make their best argument, in their own words. We trust that our readers can make their own judgement as to the validity of the arguments.
This comment is off topic. The post never mentioned LNT. I'm going to let it stand, but further off topic plugs for citizendium will be expunged.
The whole discussion of radiation harm is totally bassackwards. We start by posing the issue as pro-LNT or anti-LNT, and then immediately turn to the data, almost always low dose data where the single to noise ratio is so low it is possible to wring any conclusion you want from it.
We should start with the biology, and then come up with a radiation harm model that is consistent with that biology. And to calibrate that model we should look at populations
where the signal to noise ratio is high enough, so we can reliably separate radiation from all the confounding factors.
Sorry, I should have said "people who vigorously defend harm from low levels of radiation". I made the leap to LNT, because that is the basis of their beliefs. I would love to see an article like you suggest, providing an alternative to Wikipedia's article on LNT. Bear in mind, an encyclopedia article must be neutral in tone and well sourced on every controversial fact. Advocates can have their say on the Debate page with each article.
The signal to noise ratio is very high for the Kerala study and for the radon studies. Perhaps we should move the noisy bomb survivor study to the bottom of the page.
Note re NRX cleanup.
My father was working at the Chalk River Labs in another building when the accident occurred, so he was involved with the cleanup. He died at age 89 in 2012. More famously Jimmy Carter was also involved at died at age 100.
Clearly 2 lives cruelly cut short by radiations /s
I recall dad mentioning that he went home in Deep River & measured the radioactivity on his clothes which he left on the porch of the house. The next morning he measured the radiation again and found near background. It was almost all very short lived isotopes.
Jim
I assume you are referring to the bottom line in the Green Table.
The NRX screw up was in 1952 when your father and his buddies had a vision of providing humanity with cheap electricity. Now we have a nuclear establishment whose overwhelming interest is self-preservation. Did he ever talk to you about that transition?
I don't recall mention of the transition you talk about.
In 1959 he left Chalk River & took the job of running the radioactivity standards lab at the National Research Council of Canada. So that was measuring the amount of radiation and wasn't directly involved in studying the health effects of radiation exposure.
Long been my contention that Chernobyl - the worst possible nuclear accident - is actually proof of how safe nuclear power is.
Jack — Please rearrange the 1st third of this post.
Start with “Here’s what everybody is afraid of.” and present the paragraphs on DNA damage and mis-repair.
Follow with “Here’s what we know about our cells’ ability to repair that damage.”
ONLY then, present the chart with the green highlights.
Thanks,
-cg
Chris,
The more I think about your order, the more I like it. It's logical. We spend far too much time bashing LNT when we should be talking about the basic biology after which LNT is clearly a non-starter.
When my wife applied for the Royal Canadian Mounted Police (RCMP) in 1996, she was moving along the process and in one day in the spring of 1996, as a part of this process, she received about 100 x-rays. They do this in the event an unfortunate situation arises, the police-person perishes and they need help assisting in identifying the body. She asked, "is this many x-rays in one day safe?" She was told "oh yeah, its fine, we've been doing this for years". She also had to get a few dental x-rays for this process and then later in the year, she broke her leg, which ended the hope of becoming an RCMP officer, and had to get a few more x-rays for this.
Also, I understand there is a 10 to 20 msv radiation dose with a whole body CT scan. https://www.cancer.gov/about-cancer/diagnosis-staging/ct-scans-fact-sheet
In Canada, the protection standard is 1msv/year (I assume above background radiation), but of course it varies all over the country.
So I assume occasional instances where SNT is exceeded, even by 5x or more, is OK? Thank you for your work, SNT seems far more rational and practical than LNT.
Todd,
SNT embraces the No Threshold doctrine which takes away the pro-LNTer only defense. But it means that any amount of radiation involves some risk, however tiny. But for just about all the dose rate profiles encountered in normal life that risk is equivalent to a Lost Life Expectancy of seconds or less. Risks that most people would reasonably conclude are not worth worrying about.
We would need to put numbers on your wife's dose rate profile to come up with the SNT estimate of her increase in cancer incidence, which prediction will almost certainly be overly pessimistic, since SNT was designed to err on the high side.
Her profile was obviously pretty spikey. SNT claims that a spike of 10 mSv is much worse than 10 mSv spread over say a month.
But our repair processes operate on a time scale of a few hours. This tends to smooth out very short term spikes. For such processes, it does not make much difference whether she received two 5 mSv spikes 5 minutes apart or one 10 mSv spike.
SNT makes the heroic and pessimistic assumption that it makes no difference at all, as long as the dose is received on the same day. A dose that is spread over a day, is treated as if it were all lumped together in a spike received at the start of that day. All the xrays she received in a single day would be added together, kind of a micro-LNT.
How bad this approximation is can only be determined by looking at the data. The data such as the radium dial painters says SNT is awfully pessimitic, but, since SNT recognizes our ability to repair radiation damage, it is many orders of magnitude closer to reality than LNT. In my view, it is close enough for regulatory purposes. But it is possible to make the argument that it is not close enough. It's too pessimistic.
Very good, Jack, thanks for your patience and responding to me.
Do you know how much the radiation dose is for chemotherapy and radiation treatments? I found this, but I'm not familiar with the conversion from greys to sieverts. Perhaps there is a different article that provides a better explanation, but I couldn't find one. https://pmc.ncbi.nlm.nih.gov/articles/PMC2394476/
Thanks, Todd
Todd,
The conversion factor from grays to sieverts is 1.0 for photons and electrons.
20 for alpha particles. All external doses (eg xrays) are photons. Pills are being developed that will carry electrons and alpha particles to the tumor. But except for the latter, you can just treat grays and sieverts as interchangable, although only grays (J/kg) are actually measurable. Sieverts are an ad hoc kluge which probably shoudl be done away with. But we are stuck with them for now.
Radiotherapists need very large doses delivered over a very short time in a very localized manner to kill tumors. The dose rate, timing and localization is at least as important as the total dose. Xrays are usually delivered as a series of spikes (called fractions).
The idea is
1) normal cells recover more rapidly than cancerous,
2) fractionation allows tumor cells that were in a radio resistant phrase of the cell cycle
to cycle into a more sensitive phase
3) Hypoxic (more radioresistant) tumor cells can reoxygenate between fractions..
The specialists squabble among themselves about the relative importance of (1), (2) and (3). A typical fractionation schedule is one spike of 2 Gy per day to teh target, 5 days a week.
You now just about everything I know about radiotherapy.