Talk:Radiation hormesis/Archive 2

Disrepute doesn't rub off from one article to the next

When criticizing an article in a journal, it is not appropriate to say "this journal also published this and such which is well known to be false". This type of criticism gives a journal a bad reputation only because it has the temerity to publish articles which express a non-mainstream point of view. To give an example: you could have called out Nuclear Physics B in 1974 by saying "This journal supports the cockamamie notion that string theory is a theory of quantum gravity!" Journals are supposed to publish results which are novel, and if your work is new, it probably runs afoul of some mainstream views.

So nearly all journal articles rub somebody the wrong way. Just to be clear: I do believe that HIV causes AIDS, and I do have the prejudice that an article which questions this hypothesis is probably wrong. But if a scientist did a study and interpreted this study as a refutation of this view, and the study's methods were well thought out, I would rather see the study published and mentioned. The interpretation might be faulty, even when the results are correct.

What PDBailey is probably suggesting is that the fact that the journal published an article questioning that HIV causes AIDS probably implies that the journal's peer review process might not be the best. But even the best peer review lets wrong or fraudulent results through (as recent Science and Nature scandals demonstrate), and "Annalen Der Physik" had next to no peer review when it published Einstein's famous papers. In short, demonstrating lax peer review doesn't mean that journal articles are not notable. The best way to deal with this type of thing in my opinion is to say something along these lines: a study published in a journal which is known for lax peer review standards says XYZ, although this study has been criticized because of A, and other studies P,Q,R failed to replicate the result. Then people can be made aware of the issue, without implying that all articles in this journal can be automatically ignored.Likebox (talk) 20:33, 16 December 2008 (UTC)

I am beside myself on this one. The journal is not a scholarly resource, look at the page regarding it on wikipedia, which is very well references. Association of American Physicians and Surgeons, why require that a publication be on anything but a website? While the truth can be written on a cardboard box in the alley, Wikipedia is not a place that searches for the truth, please read WP:V. PDBailey (talk) 23:13, 16 December 2008 (UTC)

What I'm saying is that verifiability can be established for an article in a less than stellar journal, even a “junk journal", if there are additional citations and references that establish its veracity. While Wikipedia is not about "truth" in the abstract, verifiability is a social notion that gets at the idea, and serves as an effective substitute. The spirit of the policy is to try to get information about the ideas out there which are as accurate as possible. So if this paper has citations and a place in the broader literature, why not include it? Mind you, I don't know if it does, but if it does, why not?Likebox (talk) 23:25, 16 December 2008 (UTC)

If it is such a great article, it will appear somewhere else. Until then, you can look at WP:QS (part of WP:V) to see how Wikipedia treats articles published in questionable sources. PDBailey (talk) 00:54, 17 December 2008 (UTC)

BTW, you should probably also read WP:MEDRS which talks about the role of primary and secondary sources in medicine related articles. PDBailey (talk) 01:06, 17 December 2008 (UTC)

Yes--- thank you, that is an important point I hadn't thought about. I think this concern can be adressed by finding a medical source on the issue, which I hope sticks to LNT.Likebox (talk) 20:28, 17 December 2008 (UTC)

No discussion, no tag

If there is no discussion about what's wrong, the tag should go away. It's only purpose right now is to give a feeling of disrepute to the article and to the subject.Likebox (talk) 20:15, 27 December 2008 (UTC)

Here are just a few comlaints.

1. Minority views are not expressed as "the adherents believe..." but instead are written as "one study finds..."
2. There is more text for the minority view than the majority view
3. The majority view should be stated first

I would make edits to fix these and remove the POV tag, but the vast majority of my edits are RVed. That does not stop the fact that this aricle has a large POV issue. PDBailey (talk) 23:52, 27 December 2008 (UTC)

I disagree with all your points:

1. The results of the studies are not the minority views--- they are individual results that have some relevance to the discussion. The minority views are introduced right in the lead as "proponents believe". The studies are a separate thing, each one has its own point to make, and some might be valid while others might be invalid independently of one another and of the validity of the hormesis hypothesis.

2. In an article called "radiation hormesis" you will expect to find more discussion of the topic of radiation hormesis. That's the nature of an article on a controversial topic, it talks about the topic.

3. The majority view is stated exactly as it should be, as a majority view, not as a solid consensus backed up by conclusive experiments. It is made clear enough that American/UN nuclear bodies don't believe this, and it is also made clear enough that nobody really knows the answer for sure.

I stand behind my claim: there is no basis for POV criticism here.Likebox (talk) 03:05, 28 December 2008 (UTC)

Likebox, I have repeatedly cited Wikipedia policies that disagree with (1), (2), and why your response to (3) is not sufficient. You do not seem to have read them or in point of fact you have not responded to them. Please identify what policies you are disagreeing with and state why they should not be applied in this case. PDBailey (talk) 17:32, 28 December 2008 (UTC)

And I have repeatedly told you my personal opinion, and didn't cite anybody. I don't like reading policies.Likebox (talk) 19:25, 28 December 2008 (UTC)

Reverting articles

If you have an issue with an article, please at least discuss WHY before reverting. Editors have no idea how to collaborate when blanket reversions are made.

Radiation Hormesis is a well-known, though highly controversial topic in radiobiology. It should be presented exactly as what it is, a proposed mechanism demonstrated in vitro but with poor Class I evidence. Djma12 ^(talk) 23:02, 29 December 2008 (UTC)

I made a mistake with that revert, sorry.

I was trying to restore the section "Studies on Low Level Radiation", which was deleted a while back, well before your edits. I am not the author of this somewhat technical section, but I did merge it into this article. It used to be a free-standing article entitled "radiation homeostasis".

Since then, this section has been deleted or moved many times, and I feel I have to defend it, because I was responsible for the merge. It is full of interesting information, and I would not like to see it deleted.Likebox (talk) 23:20, 29 December 2008 (UTC)

Also, I don't know what "class I evidence" is. Do you mean in people? If so, why not use english? If not, what do you mean?Likebox (talk) 23:22, 29 December 2008 (UTC)

Are the contents of the "Studies on Low Level Radiation" still within the article, or are they edited out in the current version?

Concerning evidence classes as used in medicine, please refer to http://en.wikipedia.org/wiki/Evidence-based_medicine#Qualification_of_evidence

Cheers Djma12 ^(talk) 23:25, 29 December 2008 (UTC)

I put it back--- there was an edit conflict I didn't notice (with you reverting my mistake-edit).Likebox (talk) 23:29, 29 December 2008 (UTC)

Ok--- I looked up what you mean by "class I evidence". To say that hormesis is a hypothesis without class I evidence is not at all an accurate representation of the current status. Hormesis doesn't even have class III evidence that is not disputed. There are people who think all the evidence for hormesis is bunk.Likebox (talk) 23:33, 29 December 2008 (UTC)

Djma12, in humans there is the study, by Thompson et al [1] that I think qualifies as class II-1 (no randomization). But the scale is not clear on what you call it when studies of this quality conflict. In cells/animals there is, as Likebox claims, class III evidence since the French body, as quoted in the article, provides the, "reports of expert committees." But here again there is conflict among "expert committees." When considering animal evidence NCRP often found serious flaws in the studies, one example of an objection is that the type of cancer in question does not occur in humans. I think the second excerpted paragraph of the BEIR VII report summarized a serious potential publication bias issue:

In chronic low-dose experiments with dogs (75 mGy/d for the duration of life), vital hematopoietic progenitors showed increased radioresistance along with renewed proliferative capacity (Seed and Kaspar 1992). Under the same conditions, a subset of animals showed an increased repair capacity as judged by the unscheduled DNA synthesis assay (Seed and Meyers 1993). Although one might interpret these observations as an adaptive effect at the cellular level, the exposed animal population experienced a high incidence of myeloid leukemia and related myeloproliferative disorders. The authors concluded that “the acquisition of radioresistance and associated repair functions under the strong selective and mutagenic pressure of chronic radiation is tied temporally and causally to leukemogenic transformation by the radiation exposure” (Seed and Kaspar 1992) [5].

My summary of this would be the question: if radioresistance is purchases at the expense of additional cancer incidence, the sense of the reported hormesis is not just the dose curve cartoon shown at the begining of the article, it is quite curious in deed. This calls into question the usefulness of any report that looks at the efficacy of a pre-dose on the dose response. PDBailey (talk) 00:16, 30 December 2008 (UTC)

Neutrality Dispute

I understand the what that tag is about, finally! You are upset that there is a list of supporting studies for hormesis without opposing studies to counterbalance them. That puts the burden on you to resolve this, by finding any studies which support hormesis, if there are any. If not, this list is a representative sample of the literature. I will put a disclaimer which should adress your concern.Likebox (talk) 00:56, 30 December 2008 (UTC)

Likebox, I would think that by now we could agree that there is a POV dispute. Typing about that fact seems absurd to me. There is not, as you say, a burden on me. There is a POV issue, and the tag helps readers understand that. I am here trying to help resolve that; the article is making significant progress, will you please leave the tag until the discussion comes to a close?

Actual outstanding issues for the NPOV include that there is too much hormesis supporting articles. A second issue is that the views should be identified as those of the authors. PDBailey (talk) 01:53, 30 December 2008 (UTC)

Where is the progress? The order of the sections getting flipped? I like this order best, actually.Likebox (talk) 02:35, 30 December 2008 (UTC)

Likebox, the progress is that the article looks much better now (thanks to an adept edit by Djma12 that we both appear to like). I can not begin to express how annoying and unhelpful it is for you to constantly remove the POV box.

The article needs to read like what is described in WP:SUBSTANTIATE, now like it currently reads. In addition, it needs a counterbalance, and I think we should move down the second paragraph of the BEIR report for that. PDBailey (talk) 00:37, 31 December 2008 (UTC)

removal of Kendall article

I just removed the text

While it is clear that a large single exposure to plutonium dioxide powder is able to cause a fatal lung cancer in monkeys (and thus it is likely that PuO2 powder is carcinogenic in humans), some studies have shown that moderate internal exposure to plutonium results in a reduction of the risk of getting cancer,.

because the authors write in the abstract, "CONCLUSION--There is evidence for an association between radiation exposure and mortality from cancer [...] although mortality from these diseases in the study population overall was below that in the general population. The central estimates of risk from this study lie above the most recent estimates of the International Commission on Radiological Protection for leukaemia (excluding chronic lymphatic leukaemia) and for all malignancies." Claiming that this supports hormesis is to distort the author's intent and either a misreading or amounts to reinterpretation (aka original research). PDBailey (talk) 01:59, 30 December 2008 (UTC)

It might have been a misreading, or a reading of a buried part of the paper which indicates that the British plus American data showed what they call a "negative risk exposure coefficient". I can't tell yet.Likebox (talk) 03:14, 30 December 2008 (UTC)

Studies in Animals and Cultures

Quick question, what's the POV in dispute and how can we work around this? Djma12 ^(talk) 00:45, 31 December 2008 (UTC)

Here's the gist of it. There's a bunch of studies that find adaptive response for radiation, and these are listed in this section. But there are no counterbalancing studies that claim that the cancer response is linear.

In my opinion, this is mainly because of one of two reasons:

1. If a study showed that cancer is linear, nobody would care, because they think "I know that already!". This is publication bias.
2. Because in point of fact, cancer response is not linear at low doses.

So we have a majority opinion--- that cancer is linear--- which is not well supported by the primary literature. There are several studies that give mechanism and evidence that it isn't true. But it still might be true.

So PDBailey is requesting that these studies be placed with a counterbalancing collection of studies that support the mainstream view (LNT). But these counterbalancing studies don't exist, either because of publication bias, or becuase LNT is wrong. So he wants to put a bunch of secondary literature, the opinion of a bunch of "nuclear experts", to counterbalance the primary literature which is written by the researchers. I think this is a terrible idea, because secondary literature is just a consensus, just a bunch of people reading and coming to conclusions using social mechanisms, much like wikipedia. It's not independent knowledge, and it shouldn't be used as if it were independent knowledge.

So I suggest that the studies that support hormesis be left in, without a counterbalance. PDBailey says that violates WP:Undue_Weight, because hormesis is a minority view and LNT is the majority view. I agree that hormesis is a minority view, but I think that it does not violate WP:Undue_Weight to only put in supporting studies, becuase there is a second section that clearly says that this is a minority view. Also, I added a caveat at the beginning saying that it is possible (although I personally think that it is unlikely) that the studies are suggesting hormetic responses because of publication bias.Likebox (talk) 04:10, 31 December 2008 (UTC)

The LNT is just a standard hypothesis used to compute the possible effect of low-level radiations.

So far, no threshold effect has ever been statistically demonstrated on low-level radiations. This does not mean that no such threshold exists (studies on DNA repair demonstrate the contrary), only that nobody knows at what levels such a threshold effect could be detected. The "bunch of studies" that has found no threshold simply means that the expected threshold lies below the present detection level. The level where hormesis could be expected may be just at the detection limit, or way below - who knows?...

On the other hand, LNT is said to be "true" (or "demonstrated" or the like) by groups that want to ban nuclear energy (since if LNT is assumed to be "true", any becquerel will produce its percentage of cancers, whatever the dilution - this is a very strong incentive). But this is simply a POV, not a "common knowledge truth".

The official position so far is that since no threshold has ever been demonstrated in low-radiation effects, the LNT hypothesis should be the reference so as not to underestimate the radiation effects. But this has allways been presented as a hypothesis chosen for safety reasons, and with new data, this position may be changed. The correct formulation (for a NPOV redaction) should be something like "LNT is the official reference", not "LNT has been demonstrated" or the like (since LNT cannot be demonstrated).

Michelet-密是力-Me laisser un message 17:30, 31 December 2008 (UTC)

Actually, on rereading, I agree with you completely. But this does not change the central issue--- should we list a bunch of studies that show DNA repair, hormesis, etc., without counterbalance?Likebox (talk) 23:05, 31 December 2008 (UTC)

Yes, b/c this does not violate WP:Undue_Weight. Undue_Weight only qualifies when there are two competing viewpoints, both with reliable sources, and the article selectively chooses to publish predominately one viewpoint. In this case, the LNT model simply doesn't have any data on a minimal threshold value. For example, under Second hand smoke, the population data isn't tagged as POV simply b/c the tobacco industry doesn't have any population data to support their view.

However, if Likebox can find in vitro data supporting what level of radiation exposure HAS been linked to unrepaired double-strand damage, I strongly encourage him to insert this. Again, though, the onus is on him to do so. 207.172.132.171 (talk) 23:43, 31 December 2008 (UTC)

The preceding statement was made by me. Mea culpa. Djma12 ^(talk) 00:03, 1 January 2009 (UTC)

used vs upheld

In this edit Likebox changes "upheld LNT" to "used LNT" repeatedly. On what basis is this modification made? PDBailey (talk) 13:39, 31 December 2008 (UTC)

The reason is that these studies are not specifically testing LNT, just using it as the default hypothesis. This means that even if their data could be interpreted as being hormetic, they might not notice, because they are not testing this assumption. This is why it is wrong to say "upheld LNT". When a hypothesis is not being vigorously questioned, the best you can say is "used LNT and did not notice any possible contradictions, if any".Likebox (talk) 22:16, 31 December 2008 (UTC)

"...Nuclear experts are a bunch of ninnies..."

(I am quoting a previous discussion) Don't give the nuclear experts so much credit in the lead. They don't deserve it.

They did not come to a careful conclusion after weighing all the evidence. What they did is they dismissed hormesis as unfounded, then went on to pick nits with all the studies that show hormesis one by one. One of their criticisms was that the "mechanism remains obscure" (that means "I don't see how hormesis could ever happen"), which means that they were probably all physicists and engineers. Biologist would never say that.

They discount hormesis, and their report is used to strong-arm other scientists to come to the conclusion that hormesis is bunk. If they hedge their bets a little at the very end by saying "more studies are needed", and "perhaps the effect is not strictly linear", that does not change the intent nor the contents. The intent is to marginalize hormesis studies, and to dismiss the scientists as fringe.

That's the reason I believe we should keep the language of the nuclear experts strong. It keeps the report true to its intent. Those ninnies don't deserve a shred of credit for this paradigm shift.Likebox (talk) 00:54, 1 January 2009 (UTC)

Um, I don't think that's the intent of the NRC :-) As I personally know at least one member, I can assure you that many, if not most of them actually do believe in hormesis as an in vitro phenomenon and believe that it probably also translates in some degree in vivo. Their "beef" with hormesis is that that data remains mostly in vitro and observational. Given that radiation is a potentially deadly modality, they error on the side of safety and adopt the LNT until more solid human data exists. IMHO, I don't think this is an irrational position. Read their actual position statement, it's much more nuanced than the lead would suggest. Djma12 ^(talk) 15:23, 1 January 2009 (UTC)

Ok, sorry, I was relying on the quoted sections. These were very un-nuanced.Likebox (talk) 15:55, 1 January 2009 (UTC)

Which quotations do you find to be objectionable? Perhaps I can find replacement quotations that are more balanced? Djma12 ^(talk) 15:57, 1 January 2009 (UTC)

(deindent) This one. Please do not replace it.

... the preponderance of available experimental information does not support the contention that low levels of ionizing radiation have a beneficial effect. The mechanism of any such possible effect remains obscure."

This says "we are incredulous, and we do not believe you." I think it would have been better to say something like this:

"... The experimental evidence includes a minority of studies that support hormesis and we have not been able to evaluate all of these. We find hormesis to be implausible, and therefore we continue to recommend LNT for dosage measurement until the uncertainties in the literature are worked out."

Which, come to think of it, is exactly what this Wikipedia article says.Likebox (talk) 17:05, 1 January 2009 (UTC)

I think you may be reading into the statement more than they intended. The preponderous of evidence really doesn't support that ionizing radiation is benefical on more than an in vitro level. A number of proposed in vitro mechanisms exist, but none of them have been validated in human studies. The NRC actually HAS evaluated all the radiation hormesis studies -- they simply find them to be incomplete, not implausible. It is not the role of a regulatory committee to spearhead research, they merely evaluate the available data.

They also acknowledge the possibility of alternative mechanisms that have not been fully explored with "However, a strictly linear dose response should not be expected in all circumstances."

At least that's how I read it. Djma12 ^(talk) 19:24, 1 January 2009 (UTC)

If that's true, I stand corrected. Sorry for misunderstanding.Likebox (talk) 21:30, 1 January 2009 (UTC)

why do these finding matter?

I have no idea why these should appear in the text of why they might matter:

• Mechanisms that mitigate reactive oxygen species generated by ionising radiation and oxidative stress.
• Apoptosis of radiation damaged cells that may undergo tumorigenesis is initiated at only few mSv.
• Cell death during meiosis of radiation damaged cells that were unsuccessfully repaired.
• The existence of a cellular signaling system that alerts neighboring cells of cellular damage.
• The activation of enzymatic DNA repair mechanisms around 10 mSv.

All of these could be summed up as follows: there is a healing response (obviously apoptosis is a "for the greater good healing") but none of this offers any evidence about linearity and really no information about possible hormesis. Can someone explain this to me? O¹⁸ (talk) 23:44, 1 January 2009 (UTC)

Different proposed mechanisms for hormesis. I personally think lumping them as a "healing response" would be a little too much condensing. I'll try to dig up some more citations when I get back in town. Djma12 ^(talk) 23:47, 1 January 2009 (UTC)

These are different mechanisms of nonlinearity/hormesis. If you have a dose of radiation, and it randomly produces 5000 cells which are cancerous, of these cells, 3400 might be immediately killed by the immune system, the rest proliferate for a while, giving rise to microscopic tumors which are then in battle with the immune system. If each battle is independent and likely won by the immune system, the chance of cancer spreading to a macroscopic size will be proportional to the initial number of cancer seeds, which is likely proportional to the dose.

If the same dose is delivered slowly, and the cells appear one by one, any immune response training to find and eliminate these cells, as well as any apoptosis caused in those cells in response to more radiation, will tilt the balance. This is the reason some people (like me) have theoretical prejudice that cancer response might be hormetic.Likebox (talk) 20:31, 2 January 2009 (UTC)

Likebox, your argument doesn't make sense to me. If you think of cancer as failure of apoptosis, then the fact that it takes a few mSv to activate the pathway suggests that there could be real problems at low doses. Again, these all seem to be repair mechanisms that have to do with response to radiation, but not non-linearity. To find non-linearity you have to have a response that is, well, non-linear. The existance of a response shows nothing. O¹⁸ (talk) 22:48, 2 January 2009 (UTC)

Actually, Likebox's argument is fairly cogent, if not purely correct radiobiologically. Just as the application of heat to a cell stimulates the production of increased heat shock proteins, it has been demonstrated that exposure to low-levels of radiation to cells generates increased activity among DNA repair mechanisms. At which level dose radiation damage overwhelm this increased repair potential, and how applicable this increased repair mechanism is clinically is unknown.

That's why the section matters :-) Djma12 ^(talk) 02:03, 3 January 2009 (UTC)

(deindent) Let me say it this way: suppose you have a gun, and you shoot bullets into NYC from a plane in the stratosphere. You ask, what is the probability that someone will die? For low hit-rate, say 1 in a million, it's proportional to the firing rate. So if you fire a thousand bullets, you have double the chance of hitting as if you fire five hundred.

Ok, but what if you fire the bullets slowly, and people notice the bullets, and start to take precautions. If they start to walk outdoors less, or wear helmets, or something, then the response will be linear with a smaller slope. In this analogy, if the body starts repairing and gets an immune response, you expect the response to be less than linear.

Hormesis happens when you are shooting guns and there are already falling bullets in the sky (natural radiation). The people run and hide because, adding the bullets your gun, suddenly you cross a threshhold for helmet wearing and outdoor avoidance. With all those helmets and outdoors-avoidance, they they don't get hit by the other falling bullets as often, and you get bullet hormesis. It's not a perfect analogy, but it gets the idea across.Likebox (talk) 08:55, 3 January 2009 (UTC)

BEIR VII interpretation

Likebox's recent edit suggests that

In chronic low-dose experiments with dogs (75 mGy/d for the duration of life), vital hematopoietic progenitors showed increased radioresistance along with renewed proliferative capacity (Seed and Kaspar 1992). Under the same conditions, a subset of animals showed an increased repair capacity as judged by the unscheduled DNA synthesis assay (Seed and Meyers 1993). Although one might interpret these observations as an adaptive effect at the cellular level, the exposed animal population experienced a high incidence of myeloid leukemia and related myeloproliferative disorders. The authors concluded that “the acquisition of radioresistance and associated repair functions under the strong selective and mutagenic pressure of chronic radiation is tied temporally and causally to leukemogenic transformation by the radiation exposure” (Seed and Kaspar 1992) [2].

can be summarized as,

The pre-doseing providing radioprotection means that the pre-dosing initiated some cancer-like response, the body's adaptation to this response might give rise to hormesis.

This seems like (1) a huge interpretitive leap (the implication of cancer-like response) and also missing the point. However, constant rate pre-dosing could confer radioprotection but also be net risk increasing. The meagerness of the claim is highlighted in the blockquote. O¹⁸ (talk) 22:55, 2 January 2009 (UTC)

That quote belongs in a different section, the previous section, entitled "opinion of nuclear bodies". In fact, I'll put it there if it isn't there already. It does not belong in a section called "studies" because it is not a study, but an interpretation. The one-sentence summary I put in is to explain that the researchers who believe in hormesis are not blind to the fact that a protective response is due to induction of some cancer or pre-cancer in the tissue.Likebox (talk) 23:59, 2 January 2009 (UTC)

Likebox, From WP:UNDUE

Minority views can receive attention on pages specifically devoted to them—Wikipedia is not a paper encyclopedia. But on such pages, though a view may be described, the article should make appropriate reference to the majority viewpoint wherever relevant, and must not reflect an attempt to rewrite majority-view content strictly from the perspective of the minority view. (emphasis mine)

This combined with that paragraph being more relevant in that section means that it goes more naturally there. O¹⁸ (talk) 00:37, 3 January 2009 (UTC)

PDBailey, From WP:Don't be ridiculous

When an editor misinterprets wikipedia policy designed to exclude wacko nonsense, and uses it to bludgeon other editors into censoring a legitimate viewpoint, his or her edits are not constructive. Such edits should be reverted, no matter what.

That paragraph, combined with common sense, means that you are not right here.Likebox (talk) 01:12, 3 January 2009 (UTC)

Third party observations.

Likebox: seems to have an agenda of "debunking" the statements of regulatory agencies b/c he feels they are politically motivated. I personally feel this is unwarranted, but even if this is the case, we should stick to statements that are NPOV and verifiable per WP:RS.

Pdbailey: seems to have an agenda of "debunking" hormesis, either b/c he has already concluded that radiation at any dose is harmful, or b/c he personally feels it is implausible. Either way, let's try to stick to what the evidence actually says, and not censor relevant data b/c it conflicts with a personal viewpoint.

This whole editing process would be significantly easier if we concentrated on: a) NPOV statements b) Avoiding censorship of data

You guys both seem like reasonable and responsible editors -- I'm sure we can work on an agreeable final article :-)

Djma12 ^(talk) 02:13, 3 January 2009 (UTC)

My centeral contention is that loading this page up with tons of sentences that start, "one study finds..." is seriously misleading when expert panels like BEIR VII (see section titled, "Adaptive Response" in [3]), et al. are of the opinion that these can be misleading. I would agree that the jury is still out, on this, but I think that is all the more reason to look to secondary sources like review articles rather than the primary literature. O¹⁸ (talk) 04:34, 3 January 2009 (UTC)

You are misunderstanding my motivations. I came to this page wanting to do two things:

1. merge radiation homeostasis (which had a pro-hormesis POV) with radiation hormesis (which was Anti-hormesis)
2. make sure the resulting article didn't make hormesis look like a fringe theory.

In the course of debating PDBailey, he constantly brings up the NAS, BEIR stuff, and his POV is so anti-hormesis that I began to read the studies his way, which is that that the studies were dismissing hormesis as bunk. If it were true, this would mean that the conclusions were colored by politics, because the primary literature is so neutral on hormesis, if not somewhat supportive, that the only way the committee would have come to such a definitive dismissal of the effect is if they were all either politically motivated or total bozos.

Now hearing from Djma12, I find out that neither the commitee nor the report was at all anti-hormesis, and that this is only an interpretation colored by PDBailey's POV. So I now am sure that the right way to write this is as it is written, without using the report as an anti-hormesis peice, because it really isn't.Likebox (talk)

I can live with the version as it stands now. I actually think it is very good. I apologise for any hostility.Likebox (talk) 07:04, 3 January 2009 (UTC)

My goal is to get this page's evidence focused on secondary sources and consensus reports. I'll be the first to admit that the more I read from the consensus reports, the more I see that they argue this is an open question. However, a substantial amount of ink is spilled cautioning against the most obvious interpretation of the primary literature, and I think it is important for the primary litterature to be presented as such. i.e. even in the case of in vitro studies, BEIR writes

However, problems and possible artifacts of the assay system employed are also discussed. When radioresistance is observed after doses that cause some cell lethality—for example, after chronic doses that continually eliminate cells from the population—the radioresistance that emerges may be caused either (1) by some inductive phenomenon or (2) by selecting for cells that are intrinsically radioresistant. Either process 1 or process 2 could occur as the radiosensitive cells are selectively killed and thus eliminated from the population as the chronic irradiation is delivered. In the end, an adaptive or hormetic response in the population may appear to have occurred, but this would be at the expense of eliminating the sensitive or weak components in the population.[4]

I think when the in vitro section of the page has some more material in it, this is a good caution to add about interpreting these studies. At the point, however, it would weigh the section to much on the cautionary side.

They also caution that summing up the cell based evidence, "It is unclear whether such competing events would result in a net gain, net loss, or no change in health status."

Again, I am pursing these secondary sources because I think interpretation of the primary literature can be very difficult, and it is massively helpful to have the thoughtful writings of expert panels who have carefully considered the evidence. O¹⁸ (talk) 16:51, 3 January 2009 (UTC)

I just wanted to add that I think these quotes are not intended to say that there is not evidence of hormesis at the cell level, or that this evidence is useful for finding a potential mechanism. It just that that evidence is not as tight as one might believe from reading the pro-hormesis primary literature. I also think that this section of the report's primary thrust is that the jury is still out, not that the decision is against hormesis. O¹⁸ (talk) 19:32, 3 January 2009 (UTC)

My 2€ as a fourth party observations (and please be indulgent for my awkward English) ;o)

• As mentioned above, LNT is just an hypothesis used to compute dose-effects on large populations scales for low expositions. It is known to be theoretically false (which can be easely demonstrated, be it only through DNA repair studies), but deliberately maintained as reference to provide a safety margin - as long as the threshold where non-linear effects can be proven remains unknown.
• Now, this is supposed to be an encyclopedia " in which every single person on the planet is given free access to the sum of all human knowledge" - and in principle, "That's our commitment". In principle, but... I have been struck by the "LNT-militancy" conveyed by articles such as Radiation hormesis, Linear no-threshold model, Radon, ...and the like. Articles that state something like "LNT has been proven", or let the reader believe that it has been the case, or suggest that LNT is the "truth", or state that "it causes x-thousand deaths per year" without mentioning the hypothesis -etc- do not give access to knowledge but on the contrary mislead the readers into thinking something that is known to be false :( They have nothing to do in this encyclopedia. At this stage, I don't care about "undue weight" or the like: since "LNT-is-the-truth" does not stand to reason, there is no way an article can suggest that "LNT-is-the-truth" and pretend to give access to any kind of knowledge - this would be obscurantism. Or else, prove me wrong in showing how LNT has been demonstrated? no statistical study ever went that far...
• This means that all these articles have to be re-written and mitigated, keeping in mind that LNT is (indeed) the reference hypothesis but nothing more, and is likely to be rejected as soon as more precise data becomes sufficiently available. Publications that present LNT as a "proven truth" either are plainly wrong or convey a LNT-POV, and in both cases have nothing to do as reliable sources. They may of course be used to demonstrate that "some publications state that LNT is true", but the article should make it plain to the reader that such position is artificial and it cannot be inferred that "LNT is true" - since it is known to be false...
• To go back to hormesis, there seems to be another confusion in the debate, about the dose-effect relationship. LNT hypothesis just means that there is a linear relation between dose and effect (the most simple model). Hormesis specifically means that the dose-effect changes its sign for small doses (and thus, becomes beneficial for small doses). But the truth in the dose-effect curve can be anywhere in between: linear with threshold, or quadratic, or... who knows? but beware - not necessarily with a chance of sign. So "hormesis" is not the opposite of "LNT" ; both can be wrong, they are not an alternative where the Law of excluded middle could apply.

Merging the articles that discuss the effect of low-level radiation exposition is probably a good idea (just click on the red link ;o). this is the real "subject", btw, and should be treated globally. Articles such as hormesis or LNT are just various hypothesis held on that subject.

Michelet-密是力-Me laisser un message 09:11, 3 January 2009 (UTC)

Taiwan yet again

The Taiwan study was identified by PDBailey as a fraud study with no scientific value, and I agree with him, and so do all the experts. It has been mentioned in some popular reports as a hormesis-supporting study, but it comes to its conclusions by comparing the young irradiated population to the much older general population of Taiwan. From this, it comes to the conclusion that the irradiation was beneficial to the health of the residents, reducing cancer rates by 95%! That kind of nonsense is what gives hormesis a bad name.

If I had to speculate, I would guess that the study was sponsored by somebody who has a legal liability for the irradiated steel. The flaw is so obvious, I can't imagine that it is an honest mistake--- it has to be out and out fraud. There is nothing that can be recovered from the study, because they don't publish any raw numbers. The reference provided is a debunking of the Taiwan study which amply justifies all the claims I am making here. To acknowledge human frailty, I was taken in by the study for a day or two also. Please don't be fooled.Likebox (talk) 22:58, 3 January 2009 (UTC)

Likebox, I agree with your assessment of the generalizability of the results, but I think the text has to reflect a claim made in the literature. Like I said in my edit, I can not access the debunking study you helpfully found, so I can not pull out some exact claim that they make, I will have to take your word for it. But can you assure me that their text says something to the effect that it has no value and not something softer? I am not sure the extent to which we can argue against it on Wikipedia without some support in the literature.

Another line of attack might be against the journal it was published in, here I think we could find good sources for its highly questionable nature. Look at the last to paragraphs on this link O¹⁸ (talk) 00:09, 4 January 2009 (UTC)

I can't assure you, because I can't read it either. Remember, not everything has to have a source, only material that is challenged. It is important that one challenges in good-faith, challenge stuff you believe is inaccurate, otherwise the whole exercise of writing an encyclopedia gets bogged down in verifying material that everybody knows is fine, in response to frivolous challenges.

I can only say, based on a previous comment, that the rebuttal reanalyzed the cancer data in the population, noted the earlier study had the obvious age flaw, and dismissed its conclusions entirely. I read the Taiwan study, and looked for data that could be used for analysis, but I couldn't find any. So I believe that the rebuttal plus the content of the original study justifies what I wrote there. These sources of course do not justify saying that the study is fraud.Likebox (talk) 01:02, 4 January 2009 (UTC)

I guess I had interpreted Djma12's (and previously your) complaints about how this article is treated as a challenge, but if we all agree... I think the claim "no scientific value" is extreme, but this paper's quality, in my opinion, makes it very difficult to argue against. O¹⁸ (talk) 03:19, 4 January 2009 (UTC)

Can someone give me a citation to this mythical Taiwanese study? I've read reviews referring to it, but never the actual article. If it's actually crap, I'm more than happy calling it such. Djma12 ^(talk) 01:09, 4 January 2009 (UTC)

I think this is it: CHEN WL, LUAN YC, SHIEH MC, et al. “Is Chronic Radiation an Effective Prophylaxis Against Cancer?” J Am Phys Surg 9(1):6-10 (2004). Available at: http://www.jpands.org/vol9no1/chen.pdfLikebox (talk) 01:15, 4 January 2009 (UTC)

possible clarifications

It would be nice for this article to more clearly step through several points:

1. "Radiation" is not a single entity. An external source of low level gamma rays is a much different creature than ingested alpha emitters that chemically concentrate in a tissue. Po-210 anyone?

2. The quantity and nature of evidence for, or against, hormesis at different levels might be presented for cellular level, organ level, animal data, and epidemilogical human data in a table with some reference links on each line?

3. Clear identification and discussion of the societal scale issue of genetic mutation and possible cumulative genetic effects separated, apart from the potential benefits for individuals. The societal question of subtle cumulative mutation becomes more pressing if hormesis is beneficial to individual lifespan or no immediate harm offered (shorter term) economic benefits from less costly nuclear power. —Preceding unsigned comment added by 76.202.141.162 (talk) 13:44, 3 April 2009 (UTC)

I agree that this would be a satisfying outline. Feel free to be bold and make these changes. O¹⁸ (talk) 14:46, 3 April 2009 (UTC)

How split is the scientific community?

Is this a "slightly minority" view (like 35%) or "fringe" view (like 1%)? It seems like it makes more *sense* - very, very, very few harmful things act in a linear no-threshold manner (in fact, I can't think of *any* - even the worst toxins usually have a level which is completely ineffectual, because the body has filtering systems.) What is the actual support for the LNT model? It seems like it's just a mistaken continuation of the excessively simplistic view of looking at damage and harm to the body in isolation, and not paying attention to how the body repairs and even improves its function (Hygiene hypothesis is a similar issue with regard to disease germs.) 128.194.250.115 (talk) 00:47, 23 March 2009 (UTC)

The reason LNT became dominant is because radiation exposure studies from the 1950s showed that molecular damage to cells is almost exactly linear in response to the dose. This extends to chromosomal damage too. So consensus was that if the damage was linear, gross effects like cancer would be linear too. This was confirmed by epidemological studies with big exposures, Hiroshima fallout data, but it was never fully confirmed for chronic low dose exposures.

The cancer studies on low levels of radiation are conflicting, but my personal reading is that overall they slightly support some small hormesis. Big experts in the radiation field have lined up against the hormesis idea, because it is derived from fringe thinking (self-correcting mechanisms in the body were a popular new-age idea). I think 70-30 is about the right split today between LNT/Hormesis, not 99%/1%. This will get sorted out fully with the next generation of large-scale studies, I hope.Likebox (talk) 01:10, 14 May 2009 (UTC)

archive

I propose archiving threads from this talk page after 180 days of inactivity. Any objections? O¹⁸ (talk) 22:11, 29 September 2009 (UTC)

Yes, I object. I would like to be able to read all the threads without going to an archive. (Corkscrew99 (talk) 22:34, 1 January 2010 (UTC))

Corkscrew99, that ship has sailed, there are already archives. The question is should we have a rule or should it happen in a haphazard fashion when someone things of it. 0¹⁸ (talk) 02:55, 2 January 2010 (UTC)

You should do it by kilobytes amassed, not days elapsed. Sometimes old material is good to keep around, especially when nothing is happening.Likebox (talk) 06:39, 1 February 2010 (UTC)

The bot allows you to specify a minimum number of days and a minimum number of threads to leave behind. I think the latter gets at what you are thinking. We could set it to 20 discussions left on the page or so. 0¹⁸ (talk) 13:42, 1 February 2010 (UTC)

Evolution?

(posted also to hormesis discussion by accident)

Why wouldn't evolution tune the organism to the natural background level of radiation? If there is an universally beneficial mechanism which is activated by 'low doses' of radiation - which are in excess of background - why would evolution not tune this 'response' to be always on? Similar tuning didn't seem to take long for tan, for example (a very similar case; the tan is 'always on' for blacks, UV-dose-dependent for whites, and absent in albino). I think those are very valid unanswered questions, which radiation hormesis proponents must answer before radiation hormesis could be accepted as scientific hypothesis.

Ahh, by the way. I do not have references for those questions. It's just what I see as the most dubious about hormesis hypothesis. I'd say that from evolutionary-biological point of view, hormesis is not a scientific theory until it explains why peak of hormesis curve would not be at natural background level.

To summarize: Hormesis hypothesis requires some 'reserve' which is not used in absence of radiation (or other harmful agent), despite being massively beneficial to the organism - to the point that it more than counters the direct damage caused by ionizing radiation or other harmful agent. Without any explanation how such suboptimal organism would evolve, and why it wouldn't evolve to the optimum, which hormesis proponents argue is to have this "defense response" turned on.

I dunno how can such questions be added without references? I'm sure if i add such a powerful statement it'll be deleted. Maybe someone can find reference to back it up? 78.56.104.90 (talk) 10:13, 28 September 2009 (UTC)

78.56.104.90, this page is for referenced facts or claims. If you would like to find someone who makes these claims in a credible journal article, please include them. I somehow doubt someone else will do the dirty work for you (if it even can be done), but you never know. O¹⁸ (talk) 19:34, 28 September 2009 (UTC)

It is not necessary to explain the why of anything in science to prove it exists. All that is necessary is an observation that it does indeed exist. Paul Studier (talk) 20:23, 28 September 2009 (UTC)

Observation like Taiwan study? Come on, how worse can it get than this. A radiation accident in fairly corrupt country, followed by fairly corrupt study showing that the accident was not at all bad. 78.56.104.90 (talk) 11:26, 29 September 2009 (UTC)

also, by the way. Radiation hormesis is a theory or hypothesis, not observation. There is huge difference between observation and theory. You can make an observation that population A has higher exposure to ionizing radiation than population B, and observation that population A has lower or higher cancer incidence than population B. From there you observe an negative correlation. The correlation does not itself imply causation, as it may be that the population A has higher rate of smoking, or age, or is poorer, than population B. Radiation hormesis is a theory/hypothesis that there is causal link between radiation and incidence of cancer; even more than that, it is a theory that there is a health benefit. This is scientifically unfounded at all. All we know about evolution tells that a particular defensive mechanism is kept in reserve and switched off unless necessary ONLY if there is a significant 'cost' associated with operation of this mechanism - significant enough that in usual circumstances having this mechanism activated results in lower reproductive fitness. Radiation hormesis proponents are too quick to jump to conclusions. They jump from correlation to causation - without properly examining other possible causes such as age difference - and worse than that they act as if there was no difference between correlation and causation at all. Then they make even worse jump from 'lower incidence of cancer' to general health benefit. That's very dubious. There is no experimental basis for concluding that there would be general health benefit, and there is no scientific basis to this conclusion. Every other defense mechanism that is switched off in absence of threat has high associated cost. Every. Immune system can kill you; autoimmune disorders are a huge problem. Permanent tan, normally a defense from ultraviolet, can maim you, at high latitudes, by blocking vitamin D production. Adrenaline and flight or fight response in general can lead to a heart attack. I can continue all day listing defense responses, each one that has an 'off' switch has significant cost. 78.56.104.90 (talk) 11:26, 29 September 2009 (UTC)

78.56.104.90, you may want to read the article associated with this talk page. Most of the evidence provided for hormesis regards little things like cells in lab experiments. there is one epidimiological study on the page, but cautions against trusting a single study are included, especially since other studies that are equally well conducted reached the opposite conclusion. O¹⁸ (talk) 14:13, 29 September 2009 (UTC)

I were talking of health effects and policy changing. A single cell evidence can not tell anything about response of the whole organism in real world to a dose which may be highly non-uniformly distributed over the cells (e.g. alpha active dust particles in lungs, those do not give low doses to any cells; those give high doses to a few cells). Furthermore, the whole body effect should, as default hypothesis, be assumed to be detrimental - for the reason that every single defense response that we know of, which activates only in presence of threat, is otherwise detrimental (which is the reason why detection mechanism would evolve in first place).

Speaking of which, there's something interesting for hormesis believers to chew on. Do the math for the minimal dose of alpha radiation which a cell could receive - a single alpha particle track. Math is very straightforward. Human cell size is about 10 micrometres, alpha particle stopping distance is about 100 micrometres, alpha particle energy about 5 MeV, and cell mass is about 1 nanogram. Q factor for alpha particles is 20. This works out to (quite roughly) about 1.6 sievert ("20*(0.5 MeV)/(1 nanogram) in sievert" for google calculator). Doesn't look like low dose to me. Suddenly, radon exposure hormesis appears much less credible. Dmtrlk (talk) 19:24, 29 September 2009 (UTC)

Your calculation is very dubious because you did not include the organ weighting factor, which for a single cell would be extremely small. In the same manner, I can calculate that the "concentration" of lysine at the active center of some enzyme is 600 mol/l, but this has very little physical meaning. --Tweenk (talk) 22:39, 16 March 2010 (UTC)

Yes, the Taiwan study is bad, and the article points this out. And yes, it is only a theory which is not the revealed truth from above. My point still stands. There is some evidence for it and it is not necessary to explain your questions in order for the theory to be accepted. For a long time the theory that the sun was bright was accepted long before the source of the heat was identified as nuclear fusion. Paul Studier (talk) 17:37, 29 September 2009 (UTC)

I'm a little wordless as of what to reply to such obvious nonsense. No, it is not necessary for a theory that sun is bright to explain why it is bright. However, a theory that sun is dark, when proposed as alternative to theory that sun is bright, would need to explain why days are brighter than nights. (by the way, I'm 78.56.104.90) Dmtrlk (talk) 19:25, 29 September 2009 (UTC)

Dmtrlk, I think we should focus on this article, what specifically about the text of this article you want to change? O¹⁸ (talk) 22:13, 29 September 2009 (UTC)

I happen to think the talk page is a good case to provide some possibly original information which would benefit readers of wikipedia. I, myself, always make sure to check talk page to the article if I am reading it, as the talk pages often contain very valuable insight (e.g. this talk page contained valuable insight regarding the fact that there are vastly different types of radiation). As for changes... for factual I'm trying to find more information as on how to calculate a dose that a cell could receive from scattering of single gamma photon, as well as single beta particle (for alpha I have it already), to go along with claims of the research of low dose effects on individual cells and cellular self repair mechanisms, as to show that this research could only be applicable to some types of radiation (or no types of radiation if the research is claiming cellular level beneficial effects from doses which cell could not possibly receive, which could very well be the case). For non factual, it would be IMO great to mention that whole-organism beneficial effects do not have to follow from activation of repair mechanisms. Dmtrlk (talk) 07:56, 30 September 2009 (UTC)

I don't understand your complaint when you write, "For non factual, it would be IMO great to mention that whole-organism beneficial effects do not have to follow from activation of repair mechanisms." What is wrong with the following claim from the article?

However, As the BEIR-VII report points out, "the presence of a true dose threshold demands totally error-free DNA damage response and repair." The specific damage they worry about is double strand breaks and the continue, "error-prone nonhomologous end joining (NHEJ) repair in postirradiation cellular response, argues strongly against a DNA repair-mediated low-dose threshold for cancer initiation"

Have you read the article? or did you not like this for some reason? O¹⁸ (talk) 19:34, 30 September 2009 (UTC)

Of course I did read the article. The implicit point of hormesis theory is that "stimulating repair mechanisms" would be beneficial. It is still possible even if repair is not 100% efficient. Imagine an organism where defense mechanisms are perfectly shut down unless dose is at 2 times natural background (in this organism's primary habitat), at which dose the repair mechanisms activate and fix 90% of damage, so that the total radiation damage is five times smaller comparing to background. Assume that this organism keeps those repair mechanisms shut down for no good reason... and there's your hormesis. Except such organism would be better off to keep repair mechanisms always activated. Dmtrlk (talk) 14:02, 4 October 2009 (UTC)

Dmtrlk, I'd love for you to add this thought, please find a reference that says that and add it to the article! O¹⁸ (talk) 16:17, 4 October 2009 (UTC)

Cohen section

I just added a POV tag to the Cohen section. This study uses an out of the mainstream research design. Even the author writes, "This is quite different from epidemiologists usually study" (p 158), and finds a result that goes against most of the literature. The national research council writes of the design that the problems associated with it make, "such studies essentially meaningless” (as cited in [5]). The claim is very strong and the source is very weak (a journal that accepts about 90% of submissions). I recommend either (a) removing the subsection or (b) finding a secondary source for the claims. 0¹⁸ (talk) 16:05, 17 March 2010 (UTC)

Cohen's gone, Sanders has gone. Soon people reading this will wonder why this this theory ever flew. --Old Moonraker (talk) 08:12, 24 March 2010 (UTC)

I think the point is the primary literature should not be the sole source for a controversial section. I would say these authors should be cited as prominent adherents but I think the French government is more prominent. 0¹⁸ (talk) 13:29, 24 March 2010 (UTC)

You link to one of the few mainstream scientific sources (BEIR VII) that uncritically supports LNT, and it is simply wrong. All other sources I've read either say that hormesis or threshold response is more probable than LNT, or that LNT is known to be overly conservative but the alternative hypotheses are not adequately supported yet.

Saying that LNT cannot be disproven using ecological studies is bogus, because the ecological fallacy is the basic assumption of LNT. Confounders are also not the answer, because Cohen analyzed 320 different confounders and combinations of them, and none of them caused the discrepancy with LNT to go away. The removed text (and the article itself) made it clear that an ecological study cannot be used to determine the actual dose-response relationship, but *can* be used to disprove LNT, which is something entirely different. Screaming "confounders!!" and "ecological fallacy!!" at Cohen's papers is just ignorance. --Tweenk (talk) 19:47, 4 August 2010 (UTC)

Tweenk, you have correctly identified the argument uniquely advanced by Cohen. Have you read the NAS report? If so, what did you make of their response to studies of cells? 0¹⁸ (talk) 02:20, 6 August 2010 (UTC)

no such thing?

Here is an interesting point about tracks per cell [6]. Several papers on low dose response, including around 1 track per cell dose rates. 0¹⁸ (talk) 18:36, 23 November 2010 (UTC)

Journal of American Physicians and Surgeons

The Association_of_American_Physicians_and_Surgeons#Journal_of_American_Physicians_and_Surgeons is not a reliable source. Click the link. Because of this, I removed the link to it. 0¹⁸ (talk) 18:11, 17 July 2011 (UTC)

BIER too technical

I don't think the BIER report quotes are too technical. They are about as technical as the French study's results that are reported. If you can find less technical quotes that say the same thing, or want to summarize them, that might be okay, but outright removing them does not make sense. 0¹⁸ (talk) 18:14, 17 July 2011 (UTC)