Talk:Linear no-threshold model/Archive 1
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This
This statement: "(i.e. the cancer a study focuses on does not exist in humans, a clear threshold could not be established in humans, the assumptions are seriously flawed)." Makes absolutely NO sense.... someone who knows what they were trying to say should fix it, or it should be removed. Not just the bad grammar, but the entire point here makes no sense. A study advocating the linear model is ignoring evidence that the non-linear thresholded model is incorrect??? Think about it... it doesn't make sense.--Jlc46 20:52, 3 August 2006 (UTC)
Cuts
- In this application the question of a threshold does not arise, so this is not strictly the LNTM.
This sentence does not make sense with respect to radiation. If a threshold "does not arise" this is an example of the LNT assumption.
The controversy over LNT is whether the assumption holds true, all the way down to trace doses. This has hugely expensive implications for public policy.
The question is:
- Is there a level of exposure below which it doesn't make sense (moral or even economic) to keep "scrubbing" the environment? Or,
- Is there no level of safe exposure and this does it make moral and economic sense to "keep scrubbing"?
Help me write about the controversy. It relates to the "precautionary principle". --Uncle Ed 16:00, 15 November 2006 (UTC)
What the LNT is good for
The LNT is useful as a model for setting an upper limit on the amount of damage done by low doses of radiation, in order to set standards for acceptable radiation doses to personel.
This is a completely different thing to making an estimate of the damage done by low doses. It's a deliberately conservative approach, used in the absence of better data.
In some cases, there is now data that indicates that the LNT is overly conservative, see radiation hormesis. In others, there's still no data, so the LNT remains the appropriate model. Even in cases where the LNT is now known to be overly conservative, there's a general reluctance to relax standards.
It may be that some day we will find cases where the LNT is insufficiently conservative, but these have yet to be discovered.
Those are the facts as I believe them to be. But there are also some authoritative government reports, and many, many political papers, that do use the LNT to estimate damage done by low doses of radiation, most famously the estimates of large numbers of casualties of the Three Mile Island and Chernobyl nuclear accidents.
I notice that the article on radiation hormesis now reads scientific consensus has now developed against the theory, and references disproving this controversial claim have been removed from that article. Oh well. We can only try. Andrewa (talk) 16:17, 14 March 2008 (UTC)
- Andrewa, almost zero radioactive material was released from TMI, and TLDs placed around the community found zero additional exposure due to TMI, LNT would predict almost zero additional cancer deaths from this. Is there a source for your claim to the contrary? Pdbailey (talk) 02:24, 27 March 2008 (UTC)
- Also, if you want to see super-linearity, see this working paper. Pdbailey (talk) 02:36, 27 March 2008 (UTC)
propose deletion from "Several scientists also disagree with the Linear No Threshold Hypothesis" on down
The reason I don't think this belongs is that there are literally hundreds of papers on the topic, but we have something much better above---the opinions of the UN, US government, and a few societies. Lets keep it short and sweet and not make this a link farm down at the bottom. Pdbailey (talk) 03:17, 10 March 2008 (UTC)
- I agree with removing the "Several scientists also disagree with X", one can always find a contrarian to fit any view point. The best way forward is to illustrate the controversy by quoting consensus studies/position statements from respected sources that are for/against LNT. That section needs some tidying up. --Diamonddavej (talk) 03:31, 27 March 2008 (UTC)
a pity
It's a pity that this article ends its introduction by quoting a reference supporting the LNT model. Surely, this is controversial, and the introduction should give both sides equal space? As it stands, all three references in the introduction are supportive, and this one is given particular prominence by placing it in the concluding paragraph.
I see this has been the subject of much discussion above. Just adding my observation! Andrewa (talk) 19:01, 12 March 2008 (UTC)
- Andrewa, there really is no equal space claim in the Wikipedia charter, it is about well referenced claims and scientific consensus. It is really rare to have the authority level that this article as in entire books written by bodies like NCRP, the UN, and the NAS that all agree. It is true that most health physicists disagree with these conclusions, as noted by the HPS societies position; and this appears in the text because it is a high quality source. I don't really see the pity, but maybe I misunderstood your point. Pdbailey (talk) 20:24, 12 March 2008 (UTC)
- Wrong on most counts. For the policy on equal space see Wikipedia:Neutral point of view#Balance and Wikipedia:Neutral point of view#Undue weight. And there's nothing particularly scientific about Wikipedia's policy of consensus.
- My point is that this reads as an endorsement of the LNT. IMO Wikipedia should avoid any such endorsement. Andrewa (talk) 01:40, 13 March 2008 (UTC)
- You miss the point when you like to Wikipedia's sense of consensus. That is not a general definition of the word, it is a definition of consensus at wikipedia. If you want a definition of scientific consensus, the closest thing to meeting the definition would probably be a NAS study. Also, I think this page clearly meets those policy statements of wikipedia, except that I think there should be less anti-LNT articles since it is so far out of the mainstream. Pdbailey (talk) 20:03, 13 March 2008 (UTC)
- Don't really know what that first sentence means. What point am I missing?
- Do you really think:
- (a) That the article as it stands avoids endorsing the LNT as a model of radiation exposure? OR
- (b) That there's scientific consensus on this model? OR
- (c) That it's appropriate for Wikipedia to endorse one side of this controversy?
- My point remains: The article currently supports use of the LNT as a model of radiation esposure. This is not generally accepted, but promoted by a those of a particular political view. Wikipedia is committed to avoiding such bias. Andrewa (talk) 16:17, 14 March 2008 (UTC)
- Yes, I think (a) is true. I think the article is encyclopedic and reports about what sources say on the topic and reports their stance on the topic. I can't say I really understand what you mean when you write, "This is not generally accepted, but promoted by a those of a particular political view." What would you say about the sentence from the NAS, "In summary, given our current state of knowledge, the most reasonable assumption is that the cancer risks from low doses of x- or gamma-rays decrease linearly with decreasing dose." Pdbailey (talk) 02:21, 27 March 2008 (UTC)
- A poll of scientists at the international Ultra-Low-Level Radiation Effects Summit in January 2006,[1] found that over 80% of the attendees think that below a certain threshold, radiation is harmless due to innate defense mechanisms (page 29 [2]). --Diamonddavej (talk) 04:19, 28 March 2008 (UTC)
- There is a saying that it can be difficult to get a person to see something when their livelihood depends on not seeing it. If you don't believe there is a non-linearity in the dose response below a certain threshold, how can you possible apply for grant money to study low doses of radiation? Pdbailey (talk) 02:11, 13 September 2008 (UTC)
- A poll of scientists at the international Ultra-Low-Level Radiation Effects Summit in January 2006,[1] found that over 80% of the attendees think that below a certain threshold, radiation is harmless due to innate defense mechanisms (page 29 [2]). --Diamonddavej (talk) 04:19, 28 March 2008 (UTC)
Neurological Damage
The idea that radiation can cause neurological damage is interesting, and it dovetails with recent ideas about the subcellular mechanisms that wire the brain. I can understand that this might be a tantalizing new clue about the nature of neuroscience. But there is no connection whatsoever between the process of embryological brain development and the signalling processes involved in cancer, and I can cite a million sources that support that (I just have to find them--- I'll do it tomorrow). There is no reason to link this effect to cancer.Likebox (talk) 04:45, 14 September 2008 (UTC)
- Great info, what are your sources for these claims? Pdbailey (talk) 13:53, 14 September 2008 (UTC)
- This is basic biology--- I will find a textbook and cite it. The cellular signalling pathways involved in cancer are now known, and they involve a variety of signalling proteins that control apoptosis. Neurology does not have any known relation to these pathways (although you might be speculating that it does--- that's great but its very original research). All I'm saying is that you shouldn't make a claim that LNT regarding cancer is supported by a study that supports linearity or superlinearity from damage to neurological development.Likebox (talk) 05:45, 15 September 2008 (UTC)
- I removed my (likely wrong) claim that no studies support LNT, thanks for finding the reference. I will look for the radon/miner data--- you lowered my confidence in hormesis to 60%, and it's only that high because of my own theoretical biases. My doubts are caused by the following:
- What is the total dosage in the miners relative to background?
- Is the radon exposure level in a mine constant or sporadically high/low?
- Is the miner data consistent with the radon-homeowner data?
- Are there systematic effects in mining (like coal dust or something) which can cause spurious cancer/mining-time correlation?
- I'll try to find the answer, and if I find out that the answers support LNT, then I am going to be completely confused. There has to be a right answer on this. It can't be both, and it can't be one or the other depending on the study. I have nothing constructive to say in my current state of ignorance.Likebox (talk) 05:07, 16 September 2008 (UTC)
- I removed my (likely wrong) claim that no studies support LNT, thanks for finding the reference. I will look for the radon/miner data--- you lowered my confidence in hormesis to 60%, and it's only that high because of my own theoretical biases. My doubts are caused by the following:
NPOV
I just rewrote the introduction to this in order to improve the NPOV. Before, the article seemed to state that the LNT model was wrong without even defining what it was, and stated that there was "some evidence" that there was a threshold without even mentioning what it was.
I have included a link to a recent review article in the Proceedings of the National Academies of Sciences.
Frankly, I don't think that we should be citing the Wade Allison talk - if he wants to make this argument he should get it published somewhere. At the very least I removed the clearly NPOV words "closely reasoned".
Mgolden 04:08, 30 July 2007 (UTC)
- The piece now has a much better balance. Added academic citation for Wade Allison, as suggested. --Old Moonraker 05:24, 30 July 2007 (UTC)
- Still need peer reviewed paper to be something. Stronger claims (i.e. that the NAS is wrong) require strong sources. They are not yet there, and I'd suggest removing that paper and it's claims. Pdbailey 01:22, 31 July 2007 (UTC)
- The paper User:Pdbailey wants to delete is published by the physics department of Oxford University, England. The author, originally a particle physicist who now teaches medical and environmental physics, has incorporated the material into a book from the Oxford University Press and I have now added this citation. The benefit of having the online sources referenced is that users may read them for themselves, without the expense of a GBP50 bill from Amazon! Old Moonraker 05:47, 31 July 2007 (UTC)
- Moonraker, these articles are often called "Grey" literature and are not held up as excellent sources. In addition, books are less throughly edited (in the peer review sense) than journal articles. It would be one think if we were debating the quality of these sources, but in this case the author contradicts a NAS study, this is the pinnacle of peer review. You may care to read the start of the hormesis page (linked at the top of the LNT article) to see the other science organizations that have commented similarly on hormesis/LNT. Pdbailey 13:31, 31 July 2007 (UTC)
- The description of the NAS study as the "pinnacle" is obviously right. However it would be wrong to leave the article without some idea of the well-qualified dissent. This doesn't have to be from Allison: however I've had a look at the WP guidelines and it specifically recommends ...university-level textbooks...published in university presses as a preferred source. This exactly describes Allison's book which was ...developed from a course given to third year students at Oxford [University]—publisher's blurb. His paper is less useful for our purpose but as it was written by an established expert (quoting from WP:V again) it does seem to be acceptable, with the added advantage of being available in full for download. His lecture notes from 24 November 2006 (now moved to "External links") are included only because they seem more accessible to the lay reader. --Old Moonraker 14:18, 31 July 2007 (UTC)
- I agree with you that the multiple references is better than either one alone in the sense that it increases accessibility and depth. I would argue that there are many, many better articles (in peer reviewed journals) that make similar arguments. But non are in line with the NAS or other authoritative bodies. I think the article should state that before the work of any dissenters should be viewed in this light, then I think the NPOV tag should be removed Pdbailey 02:07, 1 August 2007 (UTC)
- The description of the NAS study as the "pinnacle" is obviously right. However it would be wrong to leave the article without some idea of the well-qualified dissent. This doesn't have to be from Allison: however I've had a look at the WP guidelines and it specifically recommends ...university-level textbooks...published in university presses as a preferred source. This exactly describes Allison's book which was ...developed from a course given to third year students at Oxford [University]—publisher's blurb. His paper is less useful for our purpose but as it was written by an established expert (quoting from WP:V again) it does seem to be acceptable, with the added advantage of being available in full for download. His lecture notes from 24 November 2006 (now moved to "External links") are included only because they seem more accessible to the lay reader. --Old Moonraker 14:18, 31 July 2007 (UTC)
- Moonraker, these articles are often called "Grey" literature and are not held up as excellent sources. In addition, books are less throughly edited (in the peer review sense) than journal articles. It would be one think if we were debating the quality of these sources, but in this case the author contradicts a NAS study, this is the pinnacle of peer review. You may care to read the start of the hormesis page (linked at the top of the LNT article) to see the other science organizations that have commented similarly on hormesis/LNT. Pdbailey 13:31, 31 July 2007 (UTC)
- The paper User:Pdbailey wants to delete is published by the physics department of Oxford University, England. The author, originally a particle physicist who now teaches medical and environmental physics, has incorporated the material into a book from the Oxford University Press and I have now added this citation. The benefit of having the online sources referenced is that users may read them for themselves, without the expense of a GBP50 bill from Amazon! Old Moonraker 05:47, 31 July 2007 (UTC)
- Still need peer reviewed paper to be something. Stronger claims (i.e. that the NAS is wrong) require strong sources. They are not yet there, and I'd suggest removing that paper and it's claims. Pdbailey 01:22, 31 July 2007 (UTC)
[unindent] So, to sum up, the article needs to emphasise more that the NAS study has very broadly based acceptance and use a citation from a better, peer-reviewed work that indicates that there is a threshold. I would be very happy with that. --Old Moonraker 05:17, 1 August 2007 (UTC)
This is hands-down the most controversial topic in radiation protection. The National Research Council of the National Academy of Sciences convenes the Biological Effects of Ionizing Radiation (BEIR) Committee periodically to assess the state of knowledge and provide guidance for future research. They review hundreds of published articles and review and respond to comments and suggestions from the public. Seven reports have been published since 1956. Reports I, III, IV, V, and VII focused on risk of exposure to low levels of radiation. The bottom line in each report was the same – insufficient evidence to support any theory other than LNT. This conclusion is certainly not the definitive or final word on the subject. However, it does represent a consensus among some of the leading minds in the field.
I see the single biggest problem with these reports as the lack of clear and convincing data, for any theory, beyond that provided by Atomic Bomb Life Span Study (LSS). The problem remains that radiation is a relatively poor carcinogen. The risk of cancer from any one exposure is relatively insignificant (1 in 1000 or less). We all live with a 17% lifetime risk of developing fatal cancer. This makes finding a statistically significant increase in radiation-induced cancer a daunting task. Th'wing 20:07, 29 August 2007 (UTC)
Just my 2 cents: I think Th'wing summed it up perfectly. I myself I am not an expert on radiation but I have a good understanding of statistics. The main problem really is, that if you assume LNT, then in the low dosage regions the expected effects are so extremely small, that they can't be really detected by a statistical method.
I find it somewhat irritating that the NAS review uses the phrasing "the most reasonable assumption" . This is a little bit like saying "given our current state of knowledge (around 1850) the most reasonable assumption is the existence of an Äther" (which proved to be the wrong assumption...). I would find this review far more convincing if they stated that there simply seems to be no conclusive evidence in any direction (which is the reality as far as I can tell). It seems only philosophers like to admit that they don't know something :-). 84.154.32.72 23:09, 6 September 2007 (UTC)
- Äther = Æther for readers of advancing years using Br En.
- Seriously, though, how do the respected proponents of the theory come to their conclusions? I wish someone with proper knowledge could add this. For example, Allison's work seems to be applying the results of controlled medical studies to the gaps in the statistical method. This is cited in the article but not explained. --Old Moonraker 06:33, 7 September 2007 (UTC)
- One of the biggest experiments is the "megamouse" project (google for it). Unfortunately this experiment doesn't deal with the risk of cancer, but with the risk of genetic mutations. I only read summaries about this experiment. As far as I can tell for genetic mutations the data seems to point in the LNT direction; on the other hand it is also stated that it there is a strong "dose-rate" effect (so if the dose is given over a short period of time, or over a long period of time), which I (as far as I understand LNT) interpret as an argument against LNT. My meaning: It is a big difference if you get a high dose in a short timeframe or a low dose in a long timeframe; I think it is not totally impossible that if the dose per year is low enough than there isn't any effect anymore, even if the overall dose over once lifetime is not that low. It also seems that there are several studies about populations which are exposed to a higher background radiation (for example, because you have radon in your house, or you are living in an area with an increased amount of uranium in the soil). I will try to find out where to get the original studies. —Preceding unsigned comment added by 84.154.61.90 (talk) 00:25, 8 September 2007 (UTC)
The remaining question for me is does the section look like two sides wrote it. There is a lot being swept under the rug on the Addison piece (i.e. that nobody assumes that the dose response is the same at japan bomb survivor radiation levels, that tobacco and radon are well known to interact and there's no issue for LNT with that) Pdbailey 18:02, 8 September 2007 (UTC)
I think the balance is not too bad. After now reading the NAS article, I think even NAS doesn't seem to think that a threshold model is unrealistic. They simply argue that there is not enough evidence, and that the LNT model is very plausible. Besides the LNT model is very vell suited to formulate principles of radiation protection. So of course as long as there is not extremely conclusive evidence for a threshold model, there is simply no good reason to switch models.
I think the most interesting studies concerning low-dose radiation are the once about areas with a natural high background radiation. Unfortunately the problem seems to be, that you usually simply do not have the statistical infrastructure in place to really get a good comparison with other areas. Studies would be only useful, if you compared the statistics of a high-background-radiation area to a nearby area with low-background-radiation. That would require to monitor the cancer incidences as closely as possible. Unfortunately that kind of exact data usually seems not to be availabe...
By the way I found another paper, which seems to be in favor of hormesis, but I really can't judge its credibility. 84.154.23.40 23:22, 9 September 2007 (UTC)
At this time, I would propose removal of the NPOV tag form the "controversy" section. I believe it does a great job of capturing the controversy in this area without going overboard. Truth be told I think the last paragraph is out of place -- i.e. why include a few individual authors when we have collective opinions form NAS, NCRP, UNSCEAR, HPS, and ANS? But I think that the current version is close enough so as not to warrant the tag. Pdbailey 01:37, 10 October 2007 (UTC)
- Agree with removal of the tag. As the guilty party regarding the inclusion of individual scientists' views (albeit in the Chernobyl disaster effects#Other studies and claims piece), I also accept that, now more collective opinions are included, the para carries less weight than it did. I can only return to the previous discussion (above): some of the references that support the inclusions are a useful further resource for readers. --Old Moonraker 06:43, 10 October 2007 (UTC)
- Old Moonraker, my sense is that including aggregated opinions on both sides is useful and follows NPOV, I would argue that including particular papers on only one side goes against that. I would also argue that the transition to that section is now awkward and in serious need of fixing. I would, but i don't see a great way of doing it without drastically changing the intention. Undoubtedly, someone would rv my edit.
- In any case, if we do want to keep individual opinions and articles from one side, I would argue we need them from both. Parity is in order. Pdbailey 15:19, 10 October 2007 (UTC)
- Again, I am not in disagreement: the individual scientists quoted are all on one side of the argument. They were originally copied over from Chernobyl disaster effects#Other studies and claims by User:Ed Poor when LNTM was a lot shorter than it is now. There, they are lost in the generality of the topic: here is the only page where someone with a particular interest can get easy access to the external references, which I believe are of value. Are you suggesting adding quotes from individual scientists presenting the conventional viewpoint for better balance?
- I certainly don't want to contaminate the NPOV equilibrium on Radiation hormesis by putting them there. --Old Moonraker 15:48, 10 October 2007 (UTC)
- I'm proposing one of two options. (a) have individual papers that are pro-LNT and anti-LNT, or (b) have no individual papers. I would go for (b) because I think accumulated opinions are more informative to an encyclopedia reader and that including individual papers can bog down a topic that has perhaps hundreds or thousands of papers written on it. Pdbailey 16:01, 10 October 2007 (UTC)
- I certainly don't want to contaminate the NPOV equilibrium on Radiation hormesis by putting them there. --Old Moonraker 15:48, 10 October 2007 (UTC)
Note that the United States National Research Council and the French Academy of Sciences (two comparable institutions) released reports around the same time; however, one accepted LNT but other rejected it, even though they read the same literature. The differing opinions of these two institutions neatly illustrates the controversy. --Diamonddavej (talk) 04:09, 27 March 2008 (UTC)
- Diamonddavej, the reference here is [3]. It is difficult for me to judge the status of the French Academy of Sciences which looks like it might be closer related to the American Philosophical Society, I can't tell. Pdbailey (talk) 21:21, 27 March 2008 (UTC)
- This is the French Academy of Sciences-National Academy of Medicine report in English, which I reference on wiki [4]. The French National Academy of Medicine is especially instituted to respond to requests from the French government for advice. They are thus a reputable institution and are more akin the US National Academy of Science, who are also instituted to respond respond to government requests for expert opinion. Here is the French National Academy of Medicine website: [5] --Diamonddavej (talk) 03:34, 30 March 2008 (UTC)
Interesting. I just read this article first today, and clearly found it POV in *favor* of the LNT model when I got to the History section. After reading this discussion it seems that it was POV to the contrary, and in the effort to make it NPOV, it became POV in favor, at least in the History section... Example: NAS BEIR VII was the first to clearly state that there is no safe level of radiation'. The wording indicates as if they were the first to "recognize" this, and implies that the correctness of LNT is a fact. The other sections seem a lot more balanced... Gligeti (talk) 15:36, 4 February 2009 (UTC)
- The report reads, "The committee judged that the linear no-threshold model (LNT) provided the most reasonable description of the relation between low-dose exposure to ionizing radiation and the incidence of solid cancers that are induced by ionizing radiation." That suggests that they think this model is the best, not that it is absolutely a perfectly accurate description of the world. PDBailey (talk) 02:56, 5 February 2009 (UTC)
Michael Repacholi quote
I just deleted the quote of Michael Repacholi that LNT is just an assumption. I think this might have been valid a few decaids ago, but the BEIR VII report makes it clear that they think that a low dose LNT like law is plausible. see i.e. page 245, the last three paragraphs. Here they argue that human biology suggests that there is no threshold--this is not an assumption but a reasoned combination of cell biology and epidemiology, that fact is emphasized throughout the report. PDBailey (talk) 14:25, 30 June 2009 (UTC)
Evidence and opinion
A quick read of the article showed no evidence that the no threshold hypothesis has ever been shown to be true. The "controversy" section merely gives the positions of various prominent organizations.
Do our Wikipedia:Science standards tell us to distinguish between evidence and opinion? (That link went nowhere, as of this moment. Are there any standards about how to write on scientific topics?)
What are we contributors supposed to do, when everything written about a theory is speculative? Is this science, "protoscience", or what? --Uncle Ed (talk) 21:28, 31 August 2009 (UTC)
Scope of controversy
Is the controversy a scientific dispute over whether LNT is true? Or is it more a public policy dispute over whether the assumptions of the LNT model should be used to set exposure levels to radiation or chemicals?
I didn't see anything in the article about whether the advocates of LNT have expressed the willingness to withdraw their support for it, if counterexamples are found. Now don't get me wrong: I myself am not calling LNT pseudoscience (that would violate WP:NOR and WP:NPOV). I'm just pointing out that - as the article stands - it looks like the sole basis of support for the hypothesis is a series of endorsements by scientific bodies, which either elect their members or are funded by governments.
Has anyone tried to test this hypothesis? Or even proposed such a test? If so, does that change it from a "we say, you say" tussle into a scientific dispute? That is, one which can settled in due course by independent teams of scientists comparing predictions to observations? See Reproducibility. --Uncle Ed (talk) 12:38, 22 July 2010 (UTC)
- I hope my recent edit helps. The NAS reviewed available peer reviewed literature and concluded that a linear relationship is correct, rejecting a higher and a lower effect at lower dose rates. I think everyone agrees on the linear relationship at high doses. 018 (talk) 23:21, 24 July 2010 (UTC)
- I'm not sure it helps to confuse "POV" (which, strictly speaking means a "point of view") with "bias". To be neutral, our article ought to describe all points of view (i.e., "POVs") fairly.
- The dispute is not over the linear relationship at higher levels, but over whether (A) the linear relationship ends at a certain threshold or (B) the linear relationship continues all the way down to zero (or at least to undetectable levels).
- Major scientific bodies have endorsed LNT. We should say that they have done so.
- What may be less clear in the article is their reason for having issued their endorsement. Was there political pressure, or were their findings based on replicable studies?
- I wouldn't want our article to turn into a rubber stamp which endorses an endorsement! I'd prefer for us to indicate the level of support and/or opposition for LNT within the scientific community. And I'd like your help doing this. Are there polls, studies, etc. that would help us contributors discover the extend of agreement or disagreement with LNT? --Uncle Ed (talk) 19:20, 25 July 2010 (UTC)
- Ed Poor, what does a poll have to do with reality or scientific consensus? When you want a really well considered opinion on something, you go to the NAS. Their most recent report is not wishy-washy but clearly endorses LNT. The French have a huge number of reactors (and so a lot invested in this question) and they had their own body do a report on this, go checkout radiation hormesis. They find that there is lots of support for horemsis at the cellular level. The NAS study carefully considered this evidence and rejects its relevance to the question of the dose response of humans. 018 (talk) 01:32, 26 July 2010 (UTC)
- I'm not sure what the point of your questioning is. Polls could be unrelated to reality, unless of course they are polls of scientists, who presumably know better than the general public. But WP's science standards would still recommend that we write about actual cause and effect relationships, and the evidence which supports the idea that such a relationship exists.
- I don't know what place endorsements should have in this article. As far as public policy goes, endorsements might provide the sole basis. But our readers might want to know what an endorsement has to do with reality.
- Is scientific consensus relevant here? The sources I've been looking at show a distinct lack of consensus, with the various studies all contradicting each other (that's the section you deleted, by the way). Also, as you point out above, the French found support for hormesis, while the American NAS rejected it. Sounds more like a scientific dispute to me.
- But I won't edit war with you over this. If there's no editorial consensus here for the idea that LNT is not mainstream science, then I'll go along to get along. --Uncle Ed (talk) 19:18, 1 August 2010 (UTC)
But what is it?
Is there a formula for calculating the long-term effects of a specific dose under LNT? Does it apply to acute radioactive poisoning as well as stochastic effects? I was trying to get a picture of what the radioactive effects would be over time for the Fukushima plant in Japan when I got this article about the various models of predicting.
For example, what is the death rate for radiation effects predicited by LNT for, say, 2 sieverts absorbed in:
- an hour
- a day
- a month
- a year
- five years
- a lifetime?
Is there a formula that will calculate the death rate for any dosage? Are there any major effects other than death (for example, long-term neurological effects) that can be calculated? Does LNT apply to death rates at all?
Perhaps there should be a higher-level article (referrenced in the lead) on Radioactive effects over time or some such that would include the common elements of LNT, Theshold, Radiation hormesis and any other models and give some comparisons. Most of the acticle is about why and when you should use LNT rather than first explaining what it does.
In the first sentence you say that LNT is a "method for predicting the long term, biological damage". OK, before you explain about the assumptions, what is the method of predicting itself? Or is it simply and solely linear? That, for a given number of sieverts, 50% of people would die if exposed in one hour then, for the same number of sieverts, 2% (1/24 of 50%) of people would die if exposed in one day? --RoyGoldsmith (talk) 16:20, 18 March 2011 (UTC)
- The (LNT) formula for cancer death I recall is 6% per sievert, but I don't have a reference handy. So, yes there is a formula, and I agree the article would benefit from this information. This is long-timescale exposure. For short timescale, radiation sickness is the issue. Spiel496 (talk) 18:51, 20 March 2011 (UTC)
- See BEIR VII . The linear no threshold model is much more complicated than presented in this wiki page. This page needs major editing with respect to BEIR VII which describes the version of LNT accepted by major regulatory bodies. I have impression that portions of this article present some sort of strawman in regard to alleged simplicity of LNT, presenting the LNT in it's most simplified form, probably written not by any nuclear experts but by some of those folks who offer to heal people with radium springs, abandoned uranium mines, and pieces of uranium ore. 78.60.166.155 (talk) 19:06, 23 March 2011 (UTC)
- As Spiel said, this is for long term damage. For time-dependent effects, see acute radiation syndrome. As I understand, you need to be exposed to about 1 Sv within about 1 month before you experience symptoms of radiation sickness. You can detect signs of it in blood work earlier than that. LNT predicts the effect of gradual accumulation. As I understand, we predict 1 cancer death per 25 Sv exposed to any population, based on statistics done on Hiroshima & Nagasaki survivors. The formula you are looking for is something like Population_exposed * Sum_of_Dosages / 25 Sv = Increased_cancer_deaths.
- For example, expose 1,000,000 people to 100 microSieverts and you would predict 4 of them will die from cancer from that dosage. Note that 25 Sv is much higher than any one person can survive at a time, so the model only works if they are not given a lethal dosage at once. This formula is the same as the other models (such as the threshold model) except threshold models throw out very low dosages as there is no evidence to support their harmful effects. LNT is especially conservative. nakomaru (talk) 12:08, 11 April 2011 (UTC)
Baseline Cancer Risk
I feel that this article should have some brief mention of background cancer rates, background radiation levels, and the scale of other carcinogenic threats, to give a sense of perspective. If anyone can agree on what those figures should be... IDK112 (talk) 05:37, 12 September 2011 (UTC)
Questionable / Irrelevant reference ?
In Linear_no-threshold_model#Fieldwork, citing a NBER paper made by students in economy in a non peer-reviewed journal about IQ impact of radiation on Swedish children looks like a poor choice (unlike the PNAS paper cited before). I question the validity of this paper especially in regards to the topic which is the LNT model. Shouldn't we delete this ? Slb (talk) 12:01, 22 September 2011 (UTC)
- The paper now appears in one of the top economics journals (quarterly journal of economics), it should be updated to reflect that reference. Any googeling will find the paper right away. 018 (talk) 12:27, 22 September 2011 (UTC)
Self-Published Source
The inclusion of Wade Allison's self-published book in this entry may violate Wikipedia:Verifiability#Self-published_sources. While Allison is a nuclear physicist, his self-published book is on radiobiology and health physics, so it addresses medical topics outside his academic credentials. And he has no peer-reviewed papers outside pure non-biological nuclear physics cited on his university profile.
Is there any third-party publication of his views on radiobiology and health physics that satisfy the Wikipedia:Verifiability#Self-published_sources criterion : "Self-published expert sources may be considered reliable when produced by an established expert on the topic of the article whose work in the relevant field has previously been published by reliable third-party publications"? 98.204.201.124 (talk) 08:51, 15 November 2011 (UTC)
- Agreed, I removed it. 018 (talk) 21:12, 15 November 2011 (UTC)