Fear of radiation/Debate Guide

From Citizendium
Jump to navigation Jump to search
This article is developing and not approved.
 Main Article
 Discussion
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
Debate Guide [?]
 
https://en.citizendium.org/wiki/index.php?title=Fear_of_radiation/Debate_Guide&printable=yes
This is a special subpage (not present on all articles). See CZ:Subpages for more details.

Nuclear power is a controversial topic, and some of the controversies remain unsettled, even after the facts in the article are agreed on. This Debate Guide will provide a concise summary from each side of these unsettled issues. Much of this discussion is collected from Internet forums and other unreliable sources. We welcome updates with better sourcing.

Guide to Acronyms and Abbreviations

LNT - Linear No Threshold - a theory of radiation harm that is the basis for our current regulations.
SNT - Sigmoid No Threshold - an alternative theory of radiation harm that accounts for the lack of harm at low dose rates.
Units of Radiation
Bq, Gy - the simplest and most fundamental units. Becquerels (Bq) measure the intensity at a source. Grays (Gy) measure the absorption at a target. One Bq is the activity of a quantity of radioactive material in which one nucleus decays per second. One Gy is the absorption of one joule of radiation energy per kilogram of matter. One Banana has about 15 Bq of K-40. One drop of Putin's Poison has about 40 GBq (40 billion Bq) of Po-210.
Radiation Dose
Each type of radiation has a different effect on living tissue. To account for this, we have to multiply the absorbed dose in Grays by a factor RBE.
RBE - Relative Biological Effectiveness
Sv - the effective dose to humans (Sieverts) = Grays * RBE
• X-rays, γ-rays & β-rays (fast electrons): RBE = 1 (by definition)
• Slow neutrons: average RBE ≈ 3. (Variable!)
• Fast neutrons, protons & α-rays: RBE = 10.
• Fast heavy ions: RBE = 20.
See Radiation Hazards for more details on RBE.
This still doesn't account for the facts that some organs are more vulnerable than others, the harm depends on how rapidly the radiation is absorbed, and where it is absorbed. 500 milliSieverts (mSv) of alpha particles absorbed by the skin is far less harmful than the same dose ingested or inhaled.
See Wikipedia for even more details.
Jargon
Every profession has its own special names for common units. Medical people prefer REMs instead of Sieverts. Xray technicians wear badges calibrated in milliREMs. One mREM = 0.01 mSv. Radon remediation professionals prefer Curies instead of Becquerels. A typical residential radon level is one picoCurie per liter. One pCi/l = 37 Becquerels per cubic meter.

LNT Controversy

Fig.A The data for Fig.1

There is endless debate in social media over whether the Linear No Threshold (LNT) model should be used for assessing public health risks from low levels of radiation. The biggest problem with LNT is that it assumes that the harm from all radiation exposures is simply additive, and there is no healing of the damage, i.e. 1 mSv per day for a year is as bad as 365 mSv all at once.

Fig.A is the data of Fig.1 from a 52 year study of Japanese bomb survivors, with added columns for a linear fit and for the predicted excess tumors.

Fig.B Linear plot of the bomb survivor data

Fig.B is the data re-plotted on a linear scale.

The LNT model is a good fit for exposures above 200mSv, ignoring the highest point, where we might expect some kind of saturation. (A better fit would have the threshold at 100 mSv, not zero.)

The controversy is over exposures less than 200 mSv. If your exposure is 100 mSv, LNT predicts your chances of getting cancer are 0.75% higher than the normal 21%. The data from this study shows -0.07% (less cancer, not more).

For a defense of LNT, see Hold Fast to Linear No Threshold Radiation Protection by Dr. Bemnet Alemayehu, Senior Staff Scientist, Natural Resources Defense Council, 2016.

For a critique of recent studies supporting LNT, see Circling the LNT Wagons by Jack Devanney, downloaded 2024-03-13.

LNT and radon, Controversy over Figure 4

Fig.C Counties with higher radon have less lung cancer.

There is ongoing debate on the question - Is radon an exception to the studies showing that exposures less than 100 mSv do NOT follow LNT, and in fact, show no measurable harm? Does radon, unlike other sources of radiation, pose a special threat at low levels typically found in buildings (50 to 100 Bq/m3). Some (WHO and EPA) are saying yes, the risk is a simple linear extrapolation of the risk measured at higher doses, and the death rate (per EPA) exceeds even that of drunk driving. Others are saying this assumption is leading to costly and unnecessary remediation of old buildings and years of delay in solving our CO2 problem.

Figure 4 from the article is based on data from a study shown here in Figure C. A review of this study and a link to the original data can be found in section 7 of a paper at [1] "Though several authors have criticized Cohen's study, he has thoroughly rebutted those criticisms, and his study has never been refuted, ..."

Read it on the Internet:
"Scientific organizations generally support use of the LNT model ..." from the lead in Wikipedia's article on LNT (accessed 18-July-2024).

"If you had posted that graphic to Wikipedia I would have edited it already but as it is some kind of alternative to Wikipedia I’m not going to spend my Friday evening getting verified just to take down misleading information." [2]

Cohen (the source of the data in Figure C) is "a loose nut whose methodology has been debunked." [3]

"They cherry picked that tiny 2% range?!? ... That plot is total BS in my opinion. Show me the rest of the data!!!" - email 28 May 2024.

"So the question is why the negative slope [in Figure C]. I think I found a possibility. If you look at a radon contour map of the US it’s highly concentrated in the north and west. Then if you look at a contour map of where people smoke the most and, more importantly, where the laws for indoor smoking are most lenient it’s all in the south and east. So non-smokers in high radon locations get very little 2nd hand smoke. Non-smokers in low radon locations get a LOT of 2nd hand smoke. If you simply plot lung cancer vs radon in homes without controlling for that you’ll get a plot like Cohens. But it’s wrong." [4]

"The Cohen paper was reviewed and roundly rejected by the scientific community ..." [5]

Fig.D LNT theory vs measured reality for counties in the USA.

Response:
from Mike Conley, author of Earth is a Nuclear Planet, email 28 May 2024.
//
Please explain how Cohen’s study could be cherry-picked. He examined over 2,000 US counties hosting 95% of the US population, and he corrected for smoking. The results are easy to see in his graphs, one of which I reproduced for my book and is posted here.

Per the graph, lung cancer clearly downtrends in houses with higher radon levels. His study would have to be stuffed with fabricated numbers to falsify his results, and to my knowledge there is no evidence of that.

Assuming the study is not assembled from cherry-picked data, what seems confusing? I grant you that it's totally at odds with common knowledge, but sometimes science is like that. :)
//







Fig.E Relative risk of lung cancer in relation to long-term residential radon concentrations, per the European Code against Cancer 4th Edition.

Lung Cancer and Radon per the European Code:
Here is an alternative data plot. See Figure E.
There is way too much difference between these two studies to be statistical error. One or the other has to be wrong.
See the discussion at: https://www.facebook.com/groups/2081763568746983/posts/3726936500896340/?comment_id=3728618867394770

Mainstream media on radiation danger

"Contaminated water that could soon be released into the sea from the Fukushima Daiichi nuclear power plant contains radioactive carbon with the potential to damage human DNA"
"1.23 million metric tons of water stored at the plant"
"serious long-term consequences for communities and the environment"
"storage space is running out, and the government is still deciding what to do with the water."
"in addition to radioactive isotope tritium, contains radioactive isotope carbon-14, which is “major contributor to collective human radiation dose and has the potential to damage human DNA."

"CNN — When it comes to the big questions plaguing the world’s scientists, they don’t get much larger than this. Where do you safely bury more than 28,000 cubic meters – roughly six Big Ben clock towers – of deadly radioactive waste for the next million years? This is the “wicked problem” facing Germany as it closes all of its nuclear power plants in the coming years, "
"The technological challenges – of transporting the lethal waste, finding a material to encase it, and even communicating its existence to future humans – are huge.
But the most pressing challenge today might simply be finding a community willing to have a nuclear dumping ground in their backyard."
"high-level radioactive waste is the most lethal of its kind. It includes the spent fuel rods from nuclear power plants. “If you opened up a canister with those fuel rods in it, you would more or less instantly die,” said Schreurs."
"These rods are “so incredibly hot, it’s very hard to transport them safely,” said Schreurs. So for now they’re being stored in containers where they can first cool down over several decades, she added."
"Communications experts are already working on how to tell future generations thousands of years from now – when language will be completely different – not to disturb the site."

Responses:

"a grand total of 0.4 grams of C14 in all the tanks combined." (63.6 giga-Becquerels (GBq) of radioactivity). Giga sounds really huge, but compare this to the 85 million GBq from Chernobyl, or the 15 million million GBq already in the ocean, mostly from natural Potassium-40. See this chart from Woods Hole Oceanographic Institution for the sources of ocean radioactivity.

"The cost of trying to reduce harmless radiation exposures ... is exorbitant"
"Some years ago ... a forklift at the Idaho National Engineering Laboratory ... moved a small spent fuel cask from the storage pool to the hot cell. The cask had not been properly drained prior to its removal from the storage pool area, and so some pool water was dribbled onto the blacktop along the way. Despite the fact that a couple of characters had taken a midnight swim in such a pool in the days when I used to visit there and were none the worse for it, storage pool water is defined as a hazardous contaminant. It was deemed necessary, therefore, to dig up the entire path of the forklift, creating a trench two feet wide by a halfmile long that was dubbed Toomer's Creek, after the unfortunate worker whose job it was to ensure that the cask was fully drained. The ... Paving Company was hired to repave the entire road. ... used slag from the local phosphate plants as aggregate in their blacktop, which had proved to be highly satisfactory in many of the roads in the Pocatello, Idaho, area that were paved with this mix. After the job at INEL was complete, it was learned that the aggregate was naturally high in thorium and was actually more radioactive than the material that had been dug up, marked with the dreaded radiation symbol, and hauled away for expensive, long-term burial."

  • Veritasium has a video on radiation, counter to this mainstream fear-mongering.

OK, then what about the tritium:

"Perhaps the most extreme example of the unnecessary problems ... is hydrogen-3 or tritium. It is hard to imagine a less dangerous radioactive isotope than tritium. Tritium has half-life of 12.3 years and emits an extremely weak electron, so weak it is stopped by a half-inch of air. Tritium radiation is so weak it cannot be measured by a normal Geiger counter. The electron is too weak to make it through the wall of the thinnest gas tight detector tube. A tritium electron cannot penetrate the dead outer layer of your skin."

Retrieved from "https://citizendium.org/wiki/index.php?title=Fear_of_radiation/Debate_Guide&oldid=964707"