Talk:Banana equivalent dose

Banana equivalent dose

It would be helpful if all the figures in this article were also given in "banana equivalent dose"s. And perhaps there could be a table of some common sources of radiation and their activities in BEDs? xnn (talk) 16:09, 16 June 2010 (UTC)

Brazil nuts

The article states, "The most naturally radioactive food known are brazil nuts, with activity levels as high as 6600 picocuries per kg (1.875 BED)." Since one banana typically has a mass much less than 1 kg, I believe the listed banana equivalent dose would be incorrect. Unless I'm misunderstanding, one kilogram of Brazil nuts has the radioactivity of 1.875 kg of bananas. That'd be on the order of 15-20 bananas, so Brazil nuts would be 15-20 BED per kg. (Which admittedly isn't the unit being discussed by the article. Now I'm wondering whether the "other foods" section is really pertinent to this article in the first place.) --dzhim (talk) 03:24, 21 June 2010 (UTC)

• While you have a valid point, it's important to remember that a BED is a concept, not a unit. Fell Gleaming^talk 18:16, 25 June 2010 (UTC)

The article states, "A banana equivalent dose is a concept occasionally used by nuclear proponents[1][2] to place in scale the dangers of radiation by comparing exposures to the radiation generated by a common banana. [...] The banana equivalent dose is the radiation exposure received by eating a single banana [...] roughly 520 picocuries."

BED is a concept used to place a physical quantity in scale, and a BED has a defined (if imprecise) magnitude: I believe this meets the definition for a unit of measurement.

Anyway, if 1 kg of brazil nuts emits 6600 pCi radiation, and one banana emits 520 pCi, and a BED is the amount of radiation emitted by a single banana (not a kilogram of bananas), then the kilogram of nuts is 6600/520 ~= 13 BED, nowhere near the 1.875 BED stated in the article.

--dzhim (talk) 23:14, 6 September 2010 (UTC)

My point was simply in response to the suggestion that other foods may not be relevant to the article; they are, as the BED concept is wider than bananas per se. You certainly have a point about the figure being wrong; I imagine whoever put that in meant to compare them to an equivalent weight of bananas. Fell Gleaming^talk 00:05, 7 September 2010 (UTC)

Gotcha. I removed the BED number and rearranged and slightly reworded that section to hopefully make it a bit clearer. I'm still not convinced that section is needed in this article, however (though I'm not outright opposed to it). Does anyone ever talk about a "brazil nut equivalent dose" or a "potato equivalent dose," etc, (whether using a catchy term like that or not)? If so, some such uses should be mentioned in the article, e.g.:

"Comparisons to radiation from other food sources are also common. For example, Bob Smith, arguing that a nuclear plant should be built in Podunk, East Dakota, claimed that the radiation to which Podunk residents would be exposed was 'no more than that from eating seven pounds of kidney beans per day.'[1]"

Or is it in practice overwhelmingly the banana equivalent dose, similarly to how economists talk about guns and butter but not chainsaws and cream cheese, even though, as an illustration of a model, the latter would work just as well? dzhim (talk) 03:38, 7 September 2010 (UTC)

Bananas are the one I commonly hear -- however, that usage is usually followed up with an explanation of radioactivity in other foods, to drive the concept home that it's not specific to bananas. Lima beans for instance are even more radioactive ... but there are quite a few people that simply refuse to eat them.  :) Fell Gleaming^talk 12:26, 7 September 2010 (UTC)

Additions to Iodine-K40 comparisons

This new text has several problems and inaccuracies:

• It is uncited and appears to be OR|original research
• K-40 is not just a beta emitter; it has a gamma mode as well.
• I-131 is not just a gamma emitter; it also emits beta.
• While I-131 does emit a higher ratio of gamma to beta than K-40, they are at a much lower energy level (364 kEV vs 1400 MEV)
• The greater penetrating power of gamma radiation is irrelevant when the materials are biologically absorbed; The Q factor of Beta and Gamma are both 1.
• Both Iodine and Potassium are biologically necessary elements.
• While Iodine does bio-accumulate in the thyroid, thyroid cancers are among the most treatable. K-40 can cause a much wider variety of more serious and less treatable cancers.

I am thus removing it as unsalvageable. Fell Gleaming^talk 14:32, 25 June 2010 (UTC)

Synthesis

Invoking WP:SYNTH for section The homeostatic objection. There is no external source provided, that synthesises the arguments in the way given in that section. WP:SYNTH makes WP:OR and deviation from WP:NPOV. Not allowed in Wikipedia. Rursus dixit. (^mbork³!) 14:18, 6 September 2010 (UTC)

Synthesis is combining sources to reach a conclusion not expressed in any source. I think you have a point about the conclusion that the homeostatic object is false. The facts themselves should merely be presented in that section. I'm editing the section accordingly. Fell Gleaming^talk 15:33, 6 September 2010 (UTC)

"Risk of death"

According to the source, wouldn't the correct wording be "risk of death by cancer"? The way it is currently phrased does not make much sense without more concrete context, considering the risk of dying [without confining that risk to a certain time or cause] is already 100% for all living things. The section indirectly cited from the source (http://www.physics.isu.edu/radinf/risk.htm) reads as follows: "Another way of looking at risk, is to look at the Relative Risk of 1 in a million chances of dying of activities common to our society." Risk should maybe be better defined. --221.235.60.239 (talk) 11:52, 25 January 2011 (UTC)

clarify specifics of calculation

How does one calculate a banana equivalent dose specifically? Is it the radioactivity rate of an average mass of banana (perhaps adjusting for biological susceptibility), multiplied by the average amount of time for the material from an eaten banana to pass through a person's system (i.e., assuming that in the absence of any prior nutritional deficiency then the additional potassium will be excreted from the body in, what, about a day)? Or is it assuming that the potassium-40 from the banana will be entirely assimilated into the body and remain there until it all decays (or at least for many years)? It seems that there needs to be more discussion in the article of how we can estimate how much radiation dose is actually received into a person as a consequence of eating a banana (and not merely of how radioactive a fresh banana is while sitting in a crate).Cesiumfrog (talk) 00:02, 13 March 2011 (UTC)

This seemed a sensible place to put this. I just undid this Edit by [User:ClimateDragon]:

Because a normal, healthy person does not need any more potassium, most of it that is contained in a banana (radioactive or not) will be excreted after the usual transit of around 24 hours. During that time there will be some exposure but the dose will be orders of magnitude smaller than that given by the B.E.D idea.

The banana effective dose (BED) should not be taken too literally. It does not actually represent a dose you will get when eating a banana. It does show how much radiation occurs naturally.

Why? By definition, a BED is literally the radiation you will get by eating a banana. But yes, there is an issue with calculation when an actual value is attached. The assumptions made in the referenced articles are unstated and uncertain. The cited Wordpress article says:

Recall from my previous post that a banana contains about 10.92 Bq of radioactive K-40.

Run the numbers, and you find that the CEDE from eating one single banana is about 0.005 millirem.

I wish I knew exactly how he "ran the numbers"! The cited University of Nevada Environmental Health and Safety pdf, Radiation Safety says:

The amount of potassium-40 contained in a banana is 0.0528mg. This is equivalent to 14dps or 0.00037uCi. The dose equivalent, if a banana is eaten, is about 0.01 mrem.

And once again, there is a huge leap from a rate of decay events to a total biological dose per kg bodyweight. It's not that simple a calculation. You need to multiply the decay rate by the total energy per decay event (1332keV, if I'm reading this table correctly), then multiply by the total time of exposure in seconds, and (I think) divide by the mass of tissue exposed. You also have to multiply by a Quality factor, but since K40 radiation is all electrons and photons, that factor is 1. The time of exposure is pretty straightforward as ClimateDragon says. Most (almost all?) potassium ingested will be absorbed into the blood, but any excess will be excreted by the kidneys to maintain a very stable plasma concentration. I don't know about the mass of tissue exposed - is it just the whole body mass, or only the most exposed tissue? And if most radiation (beta decay) is in the gut and in the bladder, then should it be discounted for the radiation absorbed by the urine and gut contents? Anyway, using 8 hour exposure, 70kg body mass, and no discounting, I get a total exposure of about 10^-9 J/kg, or 1 nSv, or 0.01 mRem. 118.208.151.251 (talk) 12:44, 19 March 2011 (UTC)

Please state your full calculation. That seems to be what all the supposed sources of this idea are lacking. Also note that 1.3 Mev is the maximum beta energy, the average will be about half. Unlike gamma emissions, there is some billiard ball mechanics here and not all the available energy goes to the beta particle. —Preceding unsigned comment added by 95.176.126.166 (talk) 13:07, 19 March 2011 (UTC)

The wordpress article is blog content and should be removed. It is not a acceptable source and more to the point does not explain how he "runs the numbers" or what is the basis of his calculation.

The original source of BED seems to be the pdf you cite above. Sadly this also just makes an unqualified claim and gives no account of the basis of the calculation.

regards, ClimateDragon —Preceding unsigned comment added by 95.176.126.166 (talk) 13:04, 19 March 2011 (UTC)

14 Bq x 1.3/2 Mev/Bq x 1.6e-13 J/Mev / 70kg = 0.21e-13 J/kg/s Rad/s (=rem/s for beta)

8h=28800s

Dose = 6.048e-10 rem !!

Apart from the factor of two it seems we agree in principal, why is your result different? Please post you calcs. Climatedragon (talk) 13:36, 19 March 2011 (UTC)

I may have miscalculated, and will check. But regardless, your edit is inappropriate. You may disagree with the calculation of the value of a BED, but the specific concept of BED is indeed supposed to be taken literally. And unless you can cite a specific source for your claim as it stands, then it's original research. 118.208.151.251 (talk) 14:45, 19 March 2011 (UTC)

I did make a mistake in the previous post (a typo rather than a miscalc) - 1nSv is right, but that is 0.01 microrem, not millirem. I hadn't intended to give the impression that I agreed with the article's estimate of the value of a BED. Sorry about that. 118.208.151.251 (talk) 15:04, 19 March 2011 (UTC)

So when you have checked, we can see if we agree on numbers. The hps.org ref I provided in 6 states why this sort of approach to K-40 dose is wrong. Posing a request for figures and then deleting my content is wrong, especially when you don't even provide your own. Just the unsubstantiated result. Reverting my edits because of a claimed mid air collision is wrong.

The only solid ref for this whole topic is dubious because it does not state the basis or assumptions of the calculation.

You asked me to provide my figures and when I do you accuse me of WP-OR. Very funny.

Please stop your edit warring until you have established a point. — Preceding unsigned comment added by Climatedragon (talk • contribs) 15:13, 19 March 2011 (UTC)

PS Climatedragon (talk) 15:15, 19 March 2011 (UTC)

You also probably should consider how your position relates to the comparisons in the following section. Are you maintaining the K-40 in 200 bananas is equvialent of the ceasium-137 in Chernobyl muchrooms ?!

Think about it. Really. Climatedragon (talk) 15:23, 19 March 2011 (UTC)

My "position" (which you seem to have completely misunderstood) is not presented, because that's not what Wikipedia is for. It's not for presenting your "position", either. It's for presenting duly supported facts. I'll continue to remove your edit until you can present it in the appropriate way. 118.208.151.251 (talk) 15:32, 19 March 2011 (UTC)

So who put you in charge. This is sadly rather typical on WP and what makes of limited use as a reference.

I have provided a ref that shows this is inappropriate for K-40, you seem to skip over that fact. If you think it can be presented in a better way , I'm all ears. Climatedragon (talk) 15:44, 19 March 2011 (UTC)

Look, I agree with your point. You seem to skip over that fact! I don't agree with the way you're presenting it. I think that we should add a section in that goes through the specifics of calculations, or lack of them, rather than simply saying that a BED isn't supposed to be taken literally - clearly, it is intended to be taken literally. The problem is in the attributed value. 118.208.151.251 (talk) 15:49, 19 March 2011 (UTC)

Glad we basically agree. If you think such a section would be better go for it. I don't see that as a bad thing. What is a bad thing is presenting the only referenced value that is available in way that ignores that it is not applicable to potassium. I fact I have already provided a ref for.

I don't know whether the original author was being provocative or was simply totally ignorant of the biology. The ref'd paper is so trivial on its treatment it's hard to tell.

But this issue seems catch the imagination of a lot of people with a political stance on nuclear power so it seems important to put it in some factual biological context. If you can find better material with a well reasoned treatise I think what would be good and more productive than tit for tat editing.

I don't have anything better than showing the importance of the regulation of kalemie in the body why this BED idea is flawed. Climatedragon (talk) 16:50, 19 March 2011 (UTC)

Lead rewrite to improve sourcing and clarity.

This article said, "The equivalent dose for 365 bananas is 36 μSv (3.6 mrems)." This source was cited for support. The cited source quoted an earlier version of this article in support of that assertion, which is not a reliable source.

36 μSv for 365 bananas is about 0.1 μSv for each banana. At 100 rem per Sv, that is equivalent to 10 μrem, or 0.01 mrem, per banana. Explaining it this way, though, seems unnecessarily complicated.

Also, article said, "The average radioactivity is 130 Bq/kg (3 520 pCi/kg), or roughly 19.2 Bq (520 pCi) per 150 g banana.", citing a CRC handbook for support. I don't have the CRC handbook cited, but I see that this paper on Radiation Safety cited elsewhere in the article gives a figure of 370 pCi for a "medium sized" banana. That Radiation Safety paper goes on to say quite clearly that if a banana is eaten, the dose equivalent is 0.01 mrem, which it calls the "banana equivalent dose". I've changed the article to rely on the Radiation Safety paper for support of that figure.

I've removed mention of the CRC handbook. I don't think that WP:DUE requires its citation to be preserved in order to preserve mention of the different numbers of pCi per banana given by the two sources, as I think that difference is explainable by presuming that the two sources were discussing different sized bananas (i.e., a 150g banana vs. a "medium sized" banana). The 150 g banana is three bananas per pound, which seems to me more like a "large banana" size. The "medium size" banana would be about a quarter-pounder (2.2 lb/kg * 0.15 kg * 370/520 = 0.235 lb).

I googled around and found this source, which says, "12 bananas produces about 1 microsievert of radiation." That's 0.1 mrem from 12 bananas, or a bit less than .01 mrem from each banana.

I've rewritten the lead section to improve the sourcing and to clarify the explanation a bit (at least it is clearer to me than it used to be; hopefully I've improved it). I'm not a topic expert, though. If I've screwed this up, someone please correct it. Wtmitchell (talk) (earlier Boracay Bill) 05:46, 17 March 2011 (UTC)

450 g of potassium in ONE BANANA?

Uhm, guys, I'm not as wiki-savvy as I want to be, so I can't really change this myself, but 450g is about a pound. There most certainly is not a pound of potassium in an average banana. The figure you are looking for is 450mg, I believe, which requires a revision of the math. Could somebody please change this? 68.193.6.210 (talk) 06:10, 17 March 2011 (UTC)

Units

Unless the intent of this article is an ironic commentary on the plethora of units used in describing radiation doses (in which case it should sport a smilie, even though it is not very funny), it would be really helpful to have one unit (Sv?) used and put alongside each of the other uses.

Please ... quota (talk) 14:00, 17 March 2011 (UTC)

I just made this edit to the article in which, after an edit conflict, I effectively reverted some edits by User:Climatedragon. I've explained that somewhat on Climatedragon's talk page, and will expand on that here as it relates here.

Part of what Climatedragon's edits did was to try to clarify some of the differences between units of radiation and units of radiation dose equivalent, which is a problem with this article as it currently stands. There's a WP:hatnote in the Sievert article which appears to express concern over the same issue there (that article contains a link to this source, which supplies some clarification there). The hatnote there suggests a separate article which would explain this, suggesting Radiation levels as a name. I'll mention this discussion here on the talk page there (see Talk:Sievert#Should benchmark sections be split to their own page?).

I agree that explanation and clarification is needed, and that the topic is messy enough that a separate article should be devoted to the explanation. I also opine that it is a Bad Thing™ for several articles (this one, Sievert, probably others as well) to attempt separate explanations of this. I'm looking here for some expression of consensus that creating such a separate article is a good idea. The content I would envision for it would pretty much present information drawn from the two outside sourced I've linked above, and/or perhaps similar information from other sources.

Specifically regarding units of Radiation (e.g., Ci, Bq) and this article, I think that this article can and should avoid use of units other than ref and Sv (and subunits thereof, e.g., mrem, mSv).

Comments? Wtmitchell (talk) (earlier Boracay Bill) 04:24, 19 March 2011 (UTC)

Well, except that rem and sieverts aren't units of radiation I suppose that'd be fine. Charlie (Colorado) (talk) 06:18, 19 March 2011 (UTC)

Phrasing

This:

Because a normal, healthy person does not need any more potassium, most of it that is contained in a banana (radioactive or not) will be excreted after the usual transit of around 24 hours. During that time there will be some exposure but the dose will be orders of magnitude smaller than that given by the B.E.D idea.

isn't quite right. K equilibrates, but there's no guarantee -- in fact it's statistically very nearly the opposite -- that if you're full up on K you excrete the banana's potassium. Instead K atoms are exchanged throughout the body, and it's just chance whether a particular atom stays in the body or not.

This is also why the point about BAD not being realistic isn't quite right either -- the banana, once eaten, stays in the body and adds to K load until excreted by the kidneys, a period of several hours at least. This total dose does go up, by a quantity of dose-rate×that interval.

Charlie (Colorado) (talk) 06:17, 19 March 2011 (UTC)

BED assumes the K is assimilated by the body and remains there. This is grossly wrong and gives a dose several orders of magnitude greater than what you are suggesting, which seems close to the reality.

Even the original citation for BED gives NO explanation nor does it state the (false) assumptions on which it is based. —Preceding unsigned comment added by 95.176.126.166 (talk) 10:21, 19 March 2011 (UTC)

The Banana Equivalent is by definition the radiation absorbed by eating a banana, that would not have been absorbed if the banana were not eaten. Your objection seems to be one of how the actual dose is calculated - see the Clarifying Specifics of Calculation section above. 118.208.151.251 (talk) 11:53, 19 March 2011 (UTC)

Because the potassium in a banana does not emit all of its radiation the instant it is eaten, you have to measure the dose over the time period in which that extra potassium is in your body. You might note that radiation from Fukushima I has been measured in uSv/hour. There is no time period given in the University of Nevada Reno PDF, from which the 0.1 uSv value from the BED appears to come from. It seems that they mean that there is about 0.1uSv "in" the banana, but since that radiation doesn't come out all at once, we have to look at the period over which that radiation is emitted. In the case of potassium-40, its half-life is about 1.25 billion years, from which we can compute a mean lifetime of about 1.8 billion years. This value of 1.8 billion years is significantly longer than the value of 24 hours, suggested above, that the excess banana potassium remains in the body. - Afiler (talk) 23:29, 19 March 2011 (UTC)

See the Clarifying specifics of calculation section above. 0.1uSv would match up with about 1000 hours of all the K40 radiation from a banana being absorbed by 70kg of tissue. PeteSF (talk) 23:47, 19 March 2011 (UTC)

It may be that your calculations are correct, which would mean that there is an error in the University of Nevada Reno PDF, which is the only source for a value for a banana in Sieverts. If that PDF is wrong, then that means we have to rely on Wikipedia editors to do these fairly complex calculations accurately.

If we decide that we don't want to cite a particular value at all, then there is no "equivalence" in the "banana equivalent dose", then the statement of this article is basically "bananas have nonzero radiation, but we have nothing more specific to compare their radiation to". -- Afiler (talk) 00:30, 20 March 2011 (UTC)

Good grief, people. Grow up!

This was a concise and useful article a few days ago. Now it's been bastardized by a bunch of agenda-wielding wankers, and somebody got butthurt that they lost an edit war and made it a candidate for deletion. What good does that do for anybody???

This doesn't have to be a political struggle folks, it's juuuuust a little bit of pop science to help non-technical people get their heads wrapped around relative levels of danger and the wide ranging orders of magnitude involved in radiological measurements. There's nothing to argue about as long as the decimals are in about the right spot, because nobody EVER claimed it was some sort of precision measurement. It's juuuust like using a pea and a basketball three blocks apart to show the relative size of the earth and sun. That's allll it is. Calm down.

Indeed, this appears to be a much more useful version of the article. --Kvng (talk) 15:12, 20 March 2011 (UTC)

Yes, yes. It's absurd that the 'See also' section with links to different radiation units has been deleted. Davy p (talk) 18:28, 21 March 2011 (UTC)

I agree. Roll it back to the earlier version. The micromort being also the risk of driving 40km is the only useful addition since. — Preceding unsigned comment added by Innovan (talk • contribs) 03:58, 22 March 2011 (UTC)

Well trying to get any accurate information into WP is always a major political battle. Too many zealots with agendas who are not disturbed by a lack fact.

You say it was "concise and useful article a few days ago." Yes the misinformation was concise, the page layout may have been better. The big problem is this globalised urban myth is total crap.

" There's nothing to argue about as long as the decimals are in about the right spot " I totally agree. If they were I would not have been interested. The trouble is when you do calculate the BED it's about 350 times less than stated here. Since nowhere is there a link to how this is calculated or on what physics and biology it is based one can only guess at the source of the error. That in itself should negate all arguement. This is totally unsubstantiated.

I have added two refs that explain that the body chemistry of K is very important in looking at the dose but that does not seem to be enough for some. In fact there is repeated sabotage to remove and edit these sources.

But we all know that's how WP works and that's why it is of little use as a reference. — Preceding unsigned comment added by Climatedragon (talk • contribs) 08:55, 22 March 2011 (UTC)

Really disputed?

If I read the cite correctly, the dispute on whether Banana Equivalent Dose is a valid measure or not is based on a citation of an article on Boing Boing by an author of a book self-published by Lulu.com? 78.80.1.112 (talk) 03:44, 20 March 2011 (UTC) ClimateDragon's choice for a reference is to a blog article that references this very Wikipedia entry is ITS source and quotes text that no longer exists. Circular references are not acceptable and frankly sloppy. —Preceding unsigned comment added by 98.127.14.116 (talk) 22:29, 21 March 2011 (UTC)

I think there is room to point out that there is disagreement about the concept, but I think there should be a Criticism section written for that. Putting the Boing Boing link in after the opening paragraph wrecks the article, and thusly I have removed it. The link still exists in External Links, which is where it probably belongs, if it belongs at all, and if it's not being used as a citation.74.61.32.25 (talk) 07:20, 22 March 2011 (UTC)

Disputing the relevance of the concept itself in the opening is not Standard Format. Standard Format requires criticism to be at the end, much later in the article, in its own Criticism section. Having an entire quote in a break away standalone paragraph is overemphasis. And then having the entire sentence linked instead of footnoted, again, not only breaks Standard Format, but looks sad and desperate. "Radioactive iodine is exceptionally dangerous to children as it concentrates in the thyroid." is non sequitur and instead should be in a Criticism section as well. The Criticism section also has to be constructive to be useful for readers. If this model is so flawed, what are alternative, better models that are still easy to grasp for the public because it's related to something they see and do in their day-to-day lives? Most everyone has the personal experience of peeling and eating a banana. They're common, everyday objects. Peanut Butter is something more restricted to only US households, and eating "40 teaspoons" is not as easy to grasp (particularly for metric countries) as "one banana". Brazil Nuts and mushrooms are even less common to the average household. I like the cross-comparisons, but just saying "the 40 teaspoons of Peanut Butter Equivalent Dose" already shows how awkward it is. We should also somewhere be specific that the banana variety is the http://en.wikipedia.org/wiki/Grand_Nain cultivator of http://en.wikipedia.org/wiki/Cavendish_banana. The Grand Nain is the fourth most cultivated crop in the world, so much more likely to be something the average public has handled and seen in their lives. And in a later section we should probably be specific as to the weight of "one banana" and how much K and K40 are in "one banana" since people are now coming here for the math.

It's interesting in critisising the boingboing ref that you omit the fact the person quoted is former UK Atomic Energy Authority. The part of the citation got removed by an earlier editor. Maybe he felt it was not appropriate .

As such she is the ONLY competent source for this article, and neither is she some eco-loon with an agenda. Some people with agendas seem to want to propagate this urban myth at all costs and don't give a damn that it is not factual. — Preceding unsigned comment added by Climatedragon (talk • contribs) 08:44, 22 March 2011 (UTC)

Maggie Koerth-Baker is a blogger/editor who did some research in contacting Geoff Meggitt, who she quoted indirectly in the cited BoingBoing article. Geoff Meggitt (http://tamingtherays.com/) is a retired health physicist that worked with the UK Atomic Energy Authority and its commercial spin-offs. His book on the subject, Taming the Rays, is published on lulu.com, which seems to carry a stigma of vanity publishing (merited or not). Regardless, his research has been published in 2006 in the Journal of Radiological Protection. I would have loved to have corrected this, but the Wikipedia instructions on how to cite correctly made me cry. Tinfoiled (talk) 13:29, 22 March 2011 (UTC)

Who is Maggie Koerth Baker? ... and Geoff Meggitt

According to her own website http://maggiekb.com/ she is a " writer, editor and all-around idea maven based in Minneapolis, Minn. Always a sucker for random, cool facts and great stories, she now makes her living spreading interesting information far and wide. This is every bit as awesome as it sounds. She's also a contributing editor to the award-winning blog, BoingBoing.net."

Accrediting her as "former UK Atomic Energy Authority" appears to be a serious error. — Preceding unsigned comment added by Innovan (talk • contribs) 12:41, 22 March 2011 (UTC)

The original attib explaining why potassium cannot be treated like this was incorrectly attributed to Maggie, who is in fact an author and journalist (printed and web).

The UK Atomic Energy Authority source is Geoff Meggitt . 95.176.126.166 (talk) 16:23, 22 March 2011 (UTC)

More detail on his background. Sounds like a credible source on the subject

http://tamingtherays.com/

Geoff worked as a health physicist for the United Kingdom Atomic Energy Authority and its later commercial offshoots for 25 years with particular interests in risk assessment, internal dosimetry, waste management, nuclear criticality and accident response. For five years in the 1990s he was Honorary Editor of the Journal of Radiological Protection.

Since retiring in 2002 he has spent some of his time researching the history of nuclear technology and radiation protection. The results so far are a short history of nuclear criticality safety (Fission, critical mass and safety - a historical review, J Radiol Prot 26 (2006) 141-159) and this book.

Tidying Up Criticism Section

OK, so obviously we needed a Criticism Section, both to present an opposing point of view, and also to give anti-nuke zealots a place to have their say without ruining the article's purpose of explaining the idea of BED. Fair enough. But let's keep it factual, shall we?

First thing we see today: "The radioactive risk from accumulation of potassium in the thyroid gland also has to take in account how full of potassium the individual's gland already is."

Um, right. Potassium doesn't accumulate in the thyroid. That's Iodine. AFAIK, bananas are not even a source of Iodine. Thus... I'm changing references to "thyroid" to "the body".

The next sentence is also clearly related to an editor's confusion of Potassium and Iodine: "Children whose bodies are still developing have a greater risk from exposure to radiation, both because of their higher consumption of potassium while their body size increases, and from having more ongoing cell division during their growth cycle than an adult past developmental growth."

I'm removing that altogether, as this statement is unsupported by reference.

Next: "The BED can be misconstrued as implying bananas are dangerous to eat because it contrasts the commonly understood risk of eating a banana with many events considered much more risky by the uneducated public."

Huh? The whole purpose of BED is to convey the idea that very low doses of radiation are NOT dangerous. Removing this sentence because it is the editor's opinion, not supported by reference, and silly.

And finally: "So important that the thyroid gland stores potassium for later use."

There's that pesky thyroid again. Doesn't belong in this article, at least not until someone brings forward a source stating that Potassium accumulates in the thyroid. (Good luck with that).

I'm the one who suggested a Criticism Section in the first place, so obviously I should support its continued existence. But let's not make stuff up, eh?Belchfire (talk) —Preceding undated comment added 14:08, 22 March 2011 (UTC).

Thank you for the edits. :-) Don't like "whose body is already full" --it's sounds like someone is full from eating bananas, not a gland has reached max storage capacity.

The confusion on my part is I really should have written Potassium-Iodine, which I familiar with being used to saturate the thyroid during nuclear medicine. Sources: http://www.health.state.ny.us/environmental/radiological/potassium_iodide/information_for_physicians.htm http://www.anbex.com/nrc_profile_doc.php http://ki4u.com/

Eating elemental iodine by itself is poisonous. Orally, you only should take potassium-iodine. In a pinch you can use skin absorption of a painted strip of Povidone-Iodine (10%) http://www.ki4u.com/plan_b.htm but never take iodine orally by itself.

Iodine is what's stored in the thyroid, including radioactive iodine. Potassium 40 is what's radioactive in bananas. The storage of Potassium by itself, unlinked to iodine, by the thyroid is beyond my personal knowledge. Innovan (talk) 14:53, 22 March 2011 (UTC)

I guess it's not so much making stuff up but someone's failure to notice when they don't understand something. I think there is a technical point to be made and a psychological one.

The technical point is that even the equivalent dose is not a good measure for radioactive food because it doesn't tell us anything about what happens when we eat it. While the BED has probably been coined as a particularly harmless example for external exposure, the fact that a banana is food automatically makes people think of the BED as a measure for effects from radioactive food. But when seen in that context it is not appropriate.

The psychological point is that the general public has no sense of dimensions. E.g. 1,400 microsievert per day sounds a lot more dangerous than 0.7 sievert per second. Most people either fall into inappropriate panic or become inappropriately careless. The BED concept is probably quite effective at moving the public towards carelessness. Hans Adler 15:08, 22 March 2011 (UTC)

It seems that most of the pedantic nitpicking here is based on disagreement about the precision and accuracy of BED, while managing to completely ignore that BED was never intended to be a precise thing. As I stated in another section, and as the article itself states, BED is only an illustration meant to put risks in context. Obviously there are numerous factors that will sway the exact dose one way or the other, but that is entirely irrelevant to the concept as a whole. Again, as long as the decimal is in the right place, the values expressed will be sufficiently accurate to convey the idea. Arguing about how much is consumed vs how much is absorbed may or may not yield a scientifically accurate article, but it is superfluous and overly wonkish to apply those standards here. Belchfire (talk) 15:21, 22 March 2011 (UTC)

According to this source, estimates for the ratios between effective dose and committed effective dose equivalent can vary significantly for some substances: up to five orders of magnitude! Unfortunately the only concrete numbers that I found are in this paper. If these numbers are correct, then it does in fact look as if bananas are representative even for ingestion. A priori I would have expected the values for potassium to be low to medium, so that some substances may well be several orders of magnitude more dangerous. This is all not excessive pedantry but very relevant: When people think of a banana, they think of eating it, not of sitting next to it.

I am not proposing to put my "original research" into the article. I am just explaining why the critical source cannot be dismissed so easily and should be taken seriously. Hans Adler 16:06, 22 March 2011 (UTC)

If the difference is indeed five orders of magnitude, that is very significant and worthy of mention. I see nothing wrong with including such information, so long as it is not done in a way that destroys the basic idea that BED attempts to convey. Perhaps a new section explaining the various dose modes is needed? Belchfire (talk) 16:15, 22 March 2011 (UTC)

The problem is we are getting rather far from what is published about the original topic. Wikipedia can be quite good for such "original research", but not when a topic is even slightly contentious.

I just realised that I apparently misunderstood the concept of committed effective dose: It is only about the fraction that is actually ingested, and says nothing about how much is ingested. This explains why most factors in the table I found are close to 1. Maybe the source that mentions extreme variation included sources that account for typical accumulation rates, but that's just speculation. Hans Adler 16:36, 22 March 2011 (UTC)

Thank you for work on some of that totally spurious and incorrect content. There is enough of that in this whole BED-wetting article.

"OK, so obviously we needed a Criticism Section, both to present an opposing point of view, and also to give anti-nuke zealots a place to have their say without ruining the article's purpose of explaining the idea of BED. Fair enough."

This is not a case of points of view so no-one needs a special section tucked away down the page to "have their say.

"But let's keep it factual, shall we?" That what I've been trying to do for the last four days but it's an uphill battle . It seems that someone who worked for the UK nuclear industry and actually knows how the body works, and why this whole idea is wrong is not good enough for you. I guess he must be one of those anti-nuke zealots you refer to.

Now take a deep breath READ what he explains and stop sabotaging factual content because it does not fit your ideology or that ever else you have going on.

"let's keep it factual, shall we?" 95.176.126.166 (talk) 16:32, 22 March 2011 (UTC)

May I ask everybody who needs it to calm down now. An escalation helps nobody. To make an article really good we often need opposing viewpoints. The latest instance of unhelpful language, by the way, was "vandalising", which has a precise technical definition that does not apply to anything that has happened at this article so far. Using the word loosely is very strongly discouraged. Hans Adler 16:44, 22 March 2011 (UTC)

XKCD article is relevant as an External link. Please stop deleting.

The Radiation Dose chart on xkcd.com is relevant. It compares the 0.1 μSv of eating a banana to the 1μS of x-raying one arm, the 1 μSv from using a CRT for 1 year, the 5 μSv of a dental x-ray, the 40 μSv of flying from New York to LA (one-way), the 70 μSv of living in a stone, brick or concrete building for one year, the 390 μSv yearly dose from natural potassium in the body, the 1000 μSv EPA limit on yearly exposure to 1 member of the public, the 3,000 μSv of a Mammogram, the 3,650 μSv that the average person is exposed to annually (mostly through background radiation), the 5,800 μSv of a chest X-ray, the 50,000 μSv limit from the EPA for yearly exposure for any radiation worker, the 100,000 μSv amount that is the lowest amount of exposure linked to cancer, and other data NOT included in this article. And it does it in a graphical form. People who are trying to understand radiation levels through the BED are also going to appreciate the XKCD chart. 63.204.130.177 (talk) 16:45, 22 March 2011 (UTC)