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Most dangerous substance known to man

Plutonium is less toxic than vitamins and tobacco and AS toxic as lead and other heavy metals? Geez who wrote this? The precaution section needs a rewrite, please. The referenced links do not work and gamma rays aren't even considered in this article when attempting to explain the hazards of plutonium. We're led to believe that plutonium is less toxic than caffeine but just as toxic as heavy metals. There is no mention of the gamma radiation that passes through the human body at the speed of light, or the accumulation of radioactive particles that continue to poison the body long after exposure to the source (plutonium) has been discontinued.

Plutonium is not the most dangerous SUBSTANCE known to man, but is quite possibly the most dangerous ELEMENT known to man.


Furthermore, being that plutonium is largely manmade, it is no wonder that there lacks record of human deaths attributed to plutonium expsosure outside of accidents as it is handled only in a controlled, protected environments. This lack of record has to do with occurrence, not toxicity.

I propose either; 1. Rewrite this article with working references 2. Rewrite this article to reflect the truth about Plutonium toxicity issues 3. Let the conflicting statements stand. Simply deleting this is not going to resolve the issue as we will continue to debate such absurdities that plutonium is less toxic than caffeine but as toxic as lead and other heavy metals.


Plutonium is by no stretch of the imagination the most dangerous substance known to man. It will give you cancer if you inhale plutonium dust but that's true for all alpha emiters, and in any event that won't kill you for a few decades.

Also removed the stuff about radiological bombs, because plutonium isn't very radioactive (and because it is hard to get), it's not a particularly good material for a dirty bomb especially in comparison with radioactive iodine or cesium.

Well, what IS the most dangerous substance known to man, then, if it's not plutonium? Graft
Off hand, it's guess that maybe a nerve agent like sarin. Also, one could argue that refined plutonium *is* one of the most dangerous substances known to man, not because of its inherent lethality, but because you can build bombs with it and you don't want the stuff lying around where bad people can get it.
But by that logic so is hydrogen. - Omegatron 23:39, Mar 7, 2005 (UTC)
So, apparently VX has an LD-50 lower than sarin, of .008 mg/kg. Ricin does better at .001 mg/kg. By far the best is the famed botulinum toxin ('botox') at 200 pg/kg. Yow. I remember reading that one molecule of botulinum toxin is sufficient to kill a cell. Graft
Just on the logic above, about plutonium being the most dangerous substance because you can build bombs with it, that would probably make steel the most "dangerous" substance of all. You can build an a-bomb without plute, but you can't build one without steel. Nor can you build rifles, tanks or warships. Let's remember we're writing an encyclopedia article here. This sort of thing does not belong. Andrewa 11:46 Mar 8, 2003 (UTC)
Tetanus toxin is in the few tens of ng/kg, some nerve agents are IIRC in the hundreds of ug/kg, and ricin has an average lethal dose of 100 ug (so actually a tad over a/kg). One molecule of ricin can kill a cell, but it has trouble entering, and can meet the wrong structure (eg the lysosome). I don't know about botulinum toxin, but it's under an ng/kg, and lethal doses have been in the several ng. As such, Pu doesn't even come close.

Regardless of what the most dangerous substance is, it's certainly not Plutonium. Naturally-occuring Radium is about 200 times more radiotoxic. Andrewa 23:31 Mar 7, 2003 (UTC)

I don't remember specific LD-50 data, but plutonium salts are among the most toxic of all inorganic substances. N.B. that's chemical toxicity, not radiotoxicity. Mkweise 00:01 Mar 8, 2003 (UTC)
LD50 data can't by definition be used to separate chemical and radiological toxicity, it is a measure of the overall effect of the substance. So whatever the source of this information, I'd double-check that you understood them. The other strange thing about this claim is, why focus on inorganics? The organic compounds (which include of course organic salts) of heavy metals (eg lead) are normally the most deadly. Is there any reason for thinking plutonium won't be the same? It will be difficult to find out, as the radiotoxicity is high enough to mask these effects anyway. Plutonium is very nasty stuff. But not as nasty as some people want to make you think. Andrewa 11:46 Mar 8, 2003 (UTC)
My source on that is a nuclear war preparedness manual, ca. 1979, which was handed out to my class back in high school - so it is possible that it's exaggerated. It clearly states that unlike uranium, plutonium kills by (chemical) poisoning long before its radioactivity gets anywhere near dangerous levels.
Not wanting to be unkind, but this sounds like a political document. Do you remember who wrote and printed it?
As a further health warning on the above - one of the salient facts about uranium is that it kills by chemical poisoning long before its radioactivity gets anywhere near dangerous levels
The nasty thing about inorganic toxins is that they accumulate over a lifetime as well as up the food chain. (N.B. organic acid salts of heavy metals are considered inorganic toxins, since the toxic ions are inorganic.) Organic toxins, while dangerous in much lower doses, generally (with a few notable exceptions like dioxins) biodegrade very rapidly, often in a matter of days or even hours. Mkweise 03:08 Mar 11, 2003 (UTC)
Four problems here. One, the claim was about "inorganic substances", and these don't include organic salts regardless of what "inorganic toxins" might mean. So can we lay that one to rest? Two, some organic salts aren't "organic acid salts", as many metals such as plutonium, uranium and aluminium are amphoteric. Three, some salts (not many but some, and it depends a bit on the definition of a salt which is a bit controversial on this exact issue) don't ionise in food or in the body since they are not soluble in water. Four, it's not obvious what all of this is supposed to prove.
Obviously this is a complex and controversial subject, and there's a lot of misinformation and guesswork in existing literature. Beware! Andrewa 20:44 Mar 11, 2003 (UTC)
As regards Pu being one of the worst inorganics, how does it compare to dimethylmercury (organic, granted) or HCN (not sure if it's organic). For that matter, how does it compare to Cd or Hg salts? Pakaran. 00:02, 10 Aug 2004 (UTC)

I see the bit about radiological bombs has been put back in. I'm not going to remove it, for the moment at least. I think it would be good if someone a bit closer to politically neutral on the issue had a look at it.

More serious I think is the claim about first aid on the Manhatten project. It sounds like an urban myth to me, and I think it's put there to scare people. But it may be true, funny and horrible things happen in wartime. I have no evidence either way, so again I have not touched it. But maybe someone should. Andrewa 23:51 Mar 7, 2003 (UTC)

In the late 1940s a secret project was initiated to evaluate the toxicity of Plutonium and where it concentrated by injecting "Terminally Ill" patients with various amounts of Plutonium salts solutions. Usually the injected limb was amputated within a few weeks and analyzed for distribution of the Plutonium. As these were "Terminally Ill" patients, none were expected to survive more than a few years at most. However a small number of these patients did recover from their original illness, and with no significant obvious problems due to the Plutonium. At least one of these patients was still alive in the late 1980s!!! -- RTC 00:05 Mar 8, 2003 (UTC)
That would give a possible source of this myth, if myth it be. But it doesn't answer the basic question of whether there is some truth in it. I doubt it belongs in the article, myself. Andrewa 11:46 Mar 8, 2003 (UTC)
I know I'm replying to a comment made almost a year ago, but it is worth saying that the plutonium experiments undertaken by Stafford Warren were largely to assess the medical benefits of injecting plutonium (as a form of primative, direct chemotherapy), at least that was the gist of what I read about what was apparently titled Operation Sunshine (which was the not-fantastic "Plutonium Files" book which focused almost solely on the 'human story' -- important, sure, but not everything). Also, the closest thing to 'plutonium exposure' during the Manhattan Project that I've heard of is the death of a technician by radiation poisoning during experiments on the critical mass of a plutonium sphere (it was (poorly) dramatized by John Cusak in the movie Fat Man and Little Boy), after which said sad technician's body was of course put through extensive autopsy and his head, of all things, got shipped into storage or something along those lines. But I can't seem to remember offhand which book I saw that in... arggg. --Fastfission 05:48, 10 Feb 2004 (UTC)
I agree, true or false, the part about "amputation" does not belong and the proper context of the toxicity data should be made. -- RTC 00:39 Mar 11, 2003 (UTC)
Quoting from http://www.oism.org/cdp/V10_05.htm:

The most toxic substances known to man are made by bacteria. Contrary to allegations by PSR, et al., plutonium is ``not a world-class toxicant, writes T. Don Luckey in a June 20 letter to Chemical and Engineering News. When injected intraperitoneally into mice, the LD50 (the dose that causes 50% deaths in 30 days) is about the same as that of the vitamin pantothenic acid.

On a scale in which plutonium has a toxicity = 1, the toxicities of other materials are:

  • mercury chloride 100
  • strychnine 1,000
  • actinomycin D 10,000
  • tetrodotoxin 100,000
  • perfringens A toxin 1,000,000
  • pestis toxin 10,000,000
  • shigella toxin 100,000,000
  • botulinal E toxin 1,000,000,000
  • tetanus toxin 100,000,000,000
  • botulinal B toxin 1,000,000,000,000
  • botulinal D toxin 10,000,000,000,000

The EPA is more concerned about carcinogens than toxins, but plutonium doesn't make the grade there either. Plutonium-contaminated workers have a lower total cancer mortality: 88% that of unexposed workers.

End quotation -- RTC 00:40 Mar 8, 2003 (UTC)
Is that right? That's surely the result of poor statistics... otherwise you're saying that working with plutonium can help -prevent- dying of cancer. Graft
I suspect the reason for the reduction in mortality is that their employers monitor their health much more closely, so cancers in these workers are usually caught at much earlier and more treatable stages. However that is only a guess. -- RTC 22:32 Mar 11, 2003 (UTC)
Check out the article on radiation, and the new section on radiation hormesis. This is just a hypothesis, but exposure to small amounts of ionizing radiation may actually reduce the risk of cancer. RK
I read it, and it's bullshit. The argument against linear no-threshold dose-response completely misunderstands the two-hit model for cancer generation and doesn't even begin to challenge it. Graft
Have you any reasons for thinking hormesis and the two-hit model (I assume you mean Knudson’s work here) aren't compatible? They answer quite different questions. Perhaps this discussion should go to Talk:Radiation. Andrewa 18:33 Mar 14, 2003 (UTC)

I think what is important is that we try to come to a consensus as to what the key facts are, and what they key opinions are, and try to describe all of these in a readable and approachable way that makes it clear which is which.

I've had go! I'm not completely happy with the results but I'm sure they won't last too long! And I think we are making real progress.

The key question I think is what is "danger" and what is "toxicity". "Toxicity" can be measured and is a matter of fact. "Danger" is felt and is a matter of opinion. Does this help? I have not been consistent in this usage myself I realise. Andrewa 00:24 Mar 12, 2003 (UTC)


This set off my BS meter. Moving to talk until/unless someone can list a citation for this.


According to some accounts, the accepted first aid technique for tissue exposure to plutonium during the Manhattan Project was immediate high amputation of the exposed limb. This is unlikely, as the focus of the Manhatten Project was the wartime development of an important weapon and industrial safety was not a high priority. The dangers of other key materials, such as beryllium, were not researched and documented until many years afterwards.
Should probably be filed in the paper shredder right alongside scram being an acronym for safety control rod axe man. Pakaran. 00:02, 10 Aug 2004 (UTC)
I guess "according to some accounts" sounds more reputable than "I read it in a science fiction story"...
Plutonium taken into the body moves quickly to bone marrow. Nothing can be done; the victim is finished. Neutrons from it smash through the body, ionizing tissue, transmuting atoms into radioactive isotopes, destroying and killing. The fatal dose is unbelievably small; a mass a tenth the size of a grain of table salt is more than enough-a dose small enough to enter through the tiniest scratch. During the historic "Manhattan Project" immediate high amputation was considered the only possible first-aid measure.
- Robert Heinlein's short (fiction) story The Long Watch (full text here, this story begins around p. 163.) The same story also describes plutonium as the most poisonous, and most deadly metal in the known world. --Calair 23:25, 7 Mar 2005 (UTC)

---

Rewrote. The toxicity of plutonium really isn't a "controversial topic." I don't know of anyone knowledgeable either in the anti-nuclear movement or outside that will seriously defend a statement that plutonium is magically toxic.

Good rewrite. I'm still concerned that we've gone back to saying the plutonium is a "particularly deadly poison" when the evidence is that nobody ever has or ever will suffer such a fate, and that we've gone back to calling plute weapons a "category" when in fact non-plute weapons have always been rare exceptions, and that we're back to suggesting that plute might be useful as a radiological weapon, when if you blew up some spent nuclear fuel for example the fission products would be a much bigger problem than the plute. But we've made great progress on what the article said just a little while ago. Andrewa 02:27 Mar 12, 2003 (UTC)
However, you should search for HREX site:.gov on the web - there USED to be a website at Argonne/Brookhaven covering human injection experiments of Pu, and they were all primary sources. (I'm not arguing that it's magically dangerous.) Worth putting in the article? But they're gone now, you know, that whole security thing. Kind of a bummer, they were really interesting to read. Maybe someday we won't have an asshat as POTUS. Maybe someone has an archive of them. Sword 03:25, 8 Dec 2004 (UTC)

Because of its low half-life, there are only extremely tiny trace amounts of plutonium naturally.

Someone more knowledgable than I - I've been given to understand that transuranium elements simply don't occur at all naturally. Is this just a convenient oversimplification for the layperson? Is the above statement accurate? Graft

It does occur in uranium ores, due to occasional neutron capture by U-238 followed by decay to Np-239 and Pu-239. But as these events are VERY infrequent (they depend on spontanious fission rate of U-235 as well as neutron capture cross section of U-238) compared to the half-life of Pu-239, the levels can be practically ignored. I don't remember exact figures, but as I understand it the total amount of "naturally occuring" Plutonium in the entire earth is measureable in micro-gram quantities. The amount mankind has manufactured in reactors is many tons. -- RTC 02:30 Mar 14, 2003 (UTC)
The explanation is that as analytical techniques improve, previously undetectable quantities become detectable. I don't think there's any proposal to change the status of plutonium to "natural" rather than "artificial", but that's only one of several reasons that this distinction has now blurred a little. Two others are the recognition that plutonium was once more common on earth than it is now, and the discovery of natural "fossil reactor" sites in Gabon. Andrewa 17:20 Mar 14, 2003 (UTC)
Actually, any plutonium detected by "analytical techniques" is almost certainly contamination from unfissioned plutonium in the fallout from the 1940s through 1960s bomb tests. Even in modern uranium ores (as far as I know) the "naturally occuring" levels are estimates based on spontanious fission rates, capture cross sections, and decay rates. -- RTC 19:09 Mar 17, 2003 (UTC)
Webelements says "Plutonium is found in trace quantities in uranium ores but, in practice, normally it is synthesised by the transmutation of uranium. However, it is now found in very small quantities in some areas as a result of fallout from atomic bombs and from radiation leaks from nuclear facilities." I thought that mass spectrometers were now sensitive enough to detect the plutonium in uranium ores, but I could be wrong. This would not be contamination if so, as there hasn't yet been time for man-made plute to invade the geology to this extent. Andrewa 21:25 Mar 17, 2003 (UTC)

Uhm, where do we get botulin toxin (lethal dose in the ng/kg range) as being "billions of times more toxic than plutonium?" That would imply that one can survive several g/kg of plutonium, making it safer than caffeine? A gram of plutonium is probably a lethal dose I'd say, especially in soluble form. Pakaran. 04:29, 1 Mar 2004 (UTC)

According to this page, the author challenged Ralph Nader to consume as much caffeine as the author would plutonium. --NeuronExMachina 07:38, 6 Aug 2004 (UTC)
See my last edit to the article. I put the toxicity issues in context. Let me know what you think. Pakaran. 23:55, 9 Aug 2004 (UTC)
I personally think it's a lot clearer now. It may need some slight NPOV tweaking, though. --NeuronExMachina 01:48, 10 Aug 2004 (UTC)

I've converted this over to the Elements WikiProject format. Unfortunately, I've been interrupted and will have to leave it for now having made the table and folded the old text into the standardised headings format (with a few minor modifications to alter the flow -- I hope they haven't upset anybody with a strong view on the toxicity issue, but you may want to check through). Still to do:

  • Make the custom Plutonium image
  • Expand the text with the various bits and bobs that are usually put into elements.
  • Try and chase down alternate sources of data for some of the stuff that I couldn't find for the table.

Sources of data used in the table were webelements.com and environmentalchemistry.com. I will try and come back to this in the next few days if no one else sorts it out first. -- Bth 14:02, 6 Mar 2004 (UTC)

OK, the image still needs doing, but it's not the only one of the elements to need that ... --Bth 16:10, 9 Mar 2004 (UTC)



Recent added paragraph: "Orally, plutonium is less toxic than several common substances, including caffeine, acetominopnen, some vitamins, (pseudo)ephedrine, all narcotic pain killers (including codeine) and any number of plants and fungi. It is perhaps somewhat more toxic than absolute alcohol, but less so than tobacco and most illegal drugs (some such as LSD and marijuana are not or barely toxic). As such, it is debatable whether plutonium should even be classified as a poison."

This seems almost ridiculously exaggerated. Supporting quantitative evidence should be provided or it should be deleted if none can be cited.

I think the above statement is self-evident, especially with respect to aspirin, a dangerous substance that would be a precription drug if it were not grandfathered in. What is happening is that there is conflation with plutonium's use in bombs. Now radium, that is dangerous. Fred Bauder 11:59, Aug 10, 2004 (UTC)

It is great so much effort has gone into creating a fine treatment of plutonium toxicity, but does it belong on the plutonium page anymore? 5 paragraphs seems out of proportion to the rest of the article, which ought to be a mundane element page talking about melting points and isotopes.

Any reason I shouldn't say "plutonium is toxic, but no especially so." and cut and paste the rest into Plutonium Toxicity?

I think that's an excellent idea. There's still a lot of weasel-talk in the current article. Basically, some people still don't want to admit that the plute toxicity myth was and is both deliberate propaganda and a whopping big lie. The problem here is, the facts make this painfully obvious, but some significant public figures have attached their names to the myth just the same.
Criticality and proliferation issues aren't connected to toxicity except in a political sense. Ideally, we'd move all the politics into another article, perhaps Plutonium and politics, and battle out an NPOV presentation of these issues there. Andrewa 00:37, 5 Oct 2004 (UTC)
I wonder if the name has any bearing on the image of Plutonium. It does sound vaguely similar to Pollution ( "Pollute-tonium"). Just a thought.

Maybe this entire controversy should be its own page? This question of the health effects of plutonium takes up much of the article, crowding out any information about the properties of the element itself (of which there is surpringly little ...) Much of the data below could be merged in as supporting evidence, if the controversy had its own page ... —The preceding unsigned comment was added by 208.179.232.50 (talkcontribs) .

See also above. Two years after, Main article: toxicity of plutonium still sounds good. Femto 10:26, 9 October 2006 (UTC)


Vandalism - a suggestion

This talk page was vandalised by a couple of anons, who deleted sections out of some of my posts to render them nonsensical. I guess they didn't like what I said, and I think I can understand that. Telling lies about plutonium is something of an industry all of its own, and accurate Wikipedia articles threaten it.

Not that this article is perfect by any means! Lots of weasel-words in there still. That's why I think this talk page is important (and so do others, obviously).

I think I've got it back to rights. It wasn't a simple revert as there had been good-faith contributions in the meantime which I didn't want to lose, or even complicate their histories as at least one is unsigned. And I guess it will happen again, so I suggest anyone updating this page check for recent vandalism, and make your update to the last unvandalised version, which will painlessly revert the corruption. Andrewa 10:50, 18 Jan 2005 (UTC)


"complete"

What does "Complete" mean in the sentence: "Complete detonation of plutonium will produce an explosion of 20 kiloton per kilogram."?

It could be taken to mean total fission of the Pu into daugher nuclei. This would release a phenomenally huge amount of energy. Much more than 20kt/kg wouldn't it? I understand this is partially done with tritium boosting.--Deglr6328 00:46, 19 Jan 2005 (UTC)

I took it to mean fissioning of all the Pu nuclei. To check its reasonableness empirically, we could try to find figures as to the efficiency, yield and pit mass of a pure plutonium detonation, such as little boy or the trinity test. Or theoretically, I guess the figure given is just the energy release per fission (there's about 220 mev of binding energy release, which doesn't count subsequent radioactive decay which is significant in a reactor but probably not here) multiplied by the number of atoms per kilogram, so we could reperform this calculation. Can you take it from there? What leads you to believe the figure given is not reasonable?
Uh, I seem to remember reading somewhere that only 1% of available U was fissioned by the Hiroshima explosion. Of course - the energy inside an A-bomb builds up very very quickly and it explodes (and hence the mass becomes sub-critical) long before all the fissile material is consumed. So measurements from test detonations are not reliable to base this computation upon. I'm aware that the "I seem to remember reading somewhere" part is not helpful, but nonetheless this eminently theoretical figure should really be computed from quantum physics data only. DomQ 2005-08-03 19:07:53
Tritium is used for two purposes: It's a fuel for the easiest (lowest temperature and pressure) fusion reaction, and it's used as a neutron source to boost the efficiency of predominantly fission bombs. It's the second role you are describing here, and as you imply, it doesn't result in perfect efficiency by any means. Andrewa 19:56, 19 Jan 2005 (UTC)
hm. one Kg Pu239 = 4.184 mol = 2,519,665,271,966,527,196,652,720 atoms * 220MeV= 5.543263598X10^32 eV= 88,812,864,488,134 J= 21.22 Kt TNT...........huh...whadda know...just seemed too low I guess.
Anyway, the previous sentence "The critical mass for an unreflected sphere of plutonium is 16 kg, but through the use of a neutron reflecting tamper the pit of plutonium in a fission bomb is reduced to 10 kg, which is a sphere with a diameter of 10 cm." should specify the isotope that this is true for....I don't know it but prolly 239, yes?--Deglr6328 07:56, 20 Jan 2005 (UTC)

--- occurrence Dalrymble in book The Age of the Earth,1991, lists many isotopes as evidence of old earth. All isotopes t1/2>80 Myr are found in nature. Pu-244 is among them. Clearly originate from supernovae and stars just like other permanent elements (uranium, iron etc) on earth. Isotopes t1/2 <80 million yrs not found unless result of some continuing nuclear process (like short live Radon-222 from uranium etc). --MrKAT ,6 Feb 2005.

One of the problems faced by the Manhattan Project was constraining the fissile material for as long as possible before it blew itself apart. Unfortunately, that is still a constraint on obtaining anywhere near the theoritical maximum available energy.

And, in discussing critical mass, I've seen reports where the critical mass of Pu-239 was as low as 200 grams using an ideal Beryllium reflector. The Beryllium aids by adding large numbers of photo neutrons to the process.

Why reactor-grade plutonium is unsuitable for making a bomb

I thought appropriate to point out that small contents of 240Pu make the material proliferation-resistant, and why.

--Philipum 12:01, 24 May 2005 (UTC)

Reason for including mention of breaking news article?

What is the reason for including the following line about a recent "breaking" news article about a future prospect for the manufacture of Pu-238 in an encyclopedia of fact?

On June 27, 2005 a story broke in the New York Times that a reactor at INL would be used to manufacture 238Pu.

If there is actually substantial development in this area worthy of mention in an encyclopedia, then no mention of "breaking" news with the date of the article and the periodical of publication (the New York Times, with its poor science reporting anyhow) is warranted. - Centrx 21:17, 22 August 2005 (UTC)

Table obscures text

The table of various oxidation states obscures some of the text and another table - true for both IE and Firefox - could someone please fix it? Thx. 66.215.44.176 04:59, 15 November 2005 (UTC)

Moved it below the infobox. I'm yet to hear of any technical guidelines that solve these flowaround problems. Femto 13:34, 15 November 2005 (UTC)

This article is part of Wikipedia:WikiProject Elements. Elementbox converted 11:20, 17 July 2005 by Femto (previous revision was that of 01:43, 13 July 2005).

Information Sources

Some of the text in this entry was rewritten from Los Alamos National Laboratory - Plutonium. Additional text was taken from the Elements database 20001107 (via dict.org). Data for the table was obtained from the sources listed on the subject page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units.

Inhaling toxic particles

This would need to be properly sourced — my source is a Los Alamos scientist speaking informally many years ago, but it makes sense. His point was that our respiratory systems are evolved to handle all sorts of airborne hazards. Anything that actually stays in the lungs has to be of a particular combination of size and density. Too large and it gets caught in the upper respiratory system and coughed back up. Too small, and you breathe it right back out. This applies to anything, but in this case it would apply to the extremely finely powdered Pu mentioned in the text. It's not impossible for powdered Pu (or other substance) to stay in the lungs for significant amounts of time, but it's much less likely than one would guess. I've seen the same argument in discussions of why weaponizing anthrax is harder than it might seem based on the minimum amount needed to infect someone. -Dmh 16:07, 16 January 2006 (UTC)

I note that the external links on Pu toxicity take this into account in much more detail than I just gave. It would be good to move more of this into the main article. I don't have the bandwidth at the moment. -Dmh 15:28, 17 January 2006 (UTC)

Keep text and pictures together...

The text that talks about the ionic oxidation states and the pictures of the colorful test tubes are far apart. Is there something we can do to get them together? -- Pinktulip 05:23, 20 January 2006 (UTC)

No dice on moving the picture. It squashed itself and the adjacent text into the infobox, it's been shuffled around until we gave up trying. Perhaps though someone could relocate the whole oxidation state topic into the compounds section? Femto 20:37, 20 January 2006 (UTC)

Added sentence in precautions section about Fat Man and Little Boy

I added a short sentence in the Precautions section about Fat Man and Little Boy fairly accurately portraying the Louis Slotin/Harry Daghlian criticality deaths. The movie is generally derided as not very good, but in this one scene they fairly accurately portrayed a combination of the two incidents. I reviewed all documentation and photographs I could find for the Slotin/Daghlian incidents, and compared to movie scene. It seems relatively accurate and greatly helps to visualize the situation and aftermath. I've discussed the accidents with physicists and they universally comment how amazing Slotin, Daghlian, etc. worked under such primitive conditions and attempted such dangerous things. By current radiation health standards, what they did is just fantastically dangerous, but that's typical for the early immature phase of many technologies. The movie helps visualize that from the standpoint of how the test cell was configured and how the accident could happen. If anybody doesn't think the sentence belongs, feel free to remove it. Joema 19:52, 2 February 2006 (UTC)


Standardizing The Periodic Table Images

It would be nice to standardize all the periodic table images. If you look at some of the other elements (uranium for example), you'll notice the picture of the periodic table displayed on that elements page has been customized for the specific element. Aquadisco 01:53, 25 March 2006 (UTC)

The images are part of WikiProject Elements and admittedly haven't seen much work for a long time (some were never completed). If anybody wants to work on them, this would also be the place to bring in new suggestions. Femto 11:51, 25 March 2006 (UTC)

Pu 241

I believe the dominate mode of decay is beta. Am I smoking crack? The box states alpha/SF Give Peace A Chance 04:15, 6 May 2006 (UTC)

You are correct. According to the BNL website (http://www.nndc.bnl.gov/chart/reCenter.jsp?z=94&n=147) 100.00% of Pu241 is beta. Only 0.003% is alpha, and 10-14 is SF.

Metallurgy

We should probably discuss plutonium metallurgy. Every time I've read about it, it seemed fairly difficult, especially owing to the various possible crystalline phases for this metal, with significantly varying densities. Given the fact that this is fissile material, this is bound to cause delicate issues. David.Monniaux 09:18, 26 May 2006 (UTC)

Delicate issues? For posting info already in the public domain? You worry to much. Someone with sufficient means and ingenuity to obtain a critical mass of plutonium undoubtably can access more sophisticated technical info on plutonium than anything that will ever find its way into this article. Give Peace A Chance 00:31, 10 June 2006 (UTC)

I must be dense ...

Can someone explain to me (and preferably in the article, too) what the joke is in choosing Pu for Plutonium? Is it just the transposition of letters? Did someone call it Pultonium?

RandomP 21:22, 4 June 2006 (UTC)

Pinch your nose and say "peeyew". Then it will become apparent. Give Peace A Chance 22:24, 4 June 2006 (UTC)

Redirect

"Pu redirects here. Pu is also a name for Car Nicobar island in its local language."

Okay, what percentage of people will actually be searching for the other Pu? I can see a redirect on the Malaysian Wiki, but a redirect on the english one is silly. Unless anyone objects, I am removing it. Give Peace A Chance 00:20, 10 June 2006 (UTC)

Plutonium manufacture

"Since nearly all neptunium is produced in this way or consists of isotopes which decay quickly, one gets nearly pure Np-237 by chemical separation of neptunium. After this chemical separation,"

I'm not sure I understand this sentence. --Gbleem 08:03, 21 June 2006 (UTC)


This is basically just saying that Np-237 is really the only Np isotope produced. All isotopes of an element are chemically identical; hence, you cannot use chemical processes to separate different isotopes. Processes such as gaseous diffusion, centrifuges, etc. must be used to separate isotopes, and these processes are very complex and expensive. This sentence says that most of the Np created is Np-237 and that any other isotopes of Np that are created quickly decay away. Therefore, if you chemically separate Np from the reactor fuel, you will essentially have pure Np-237, whereas a chemical separation of, let's say, uranium will consist of U-235 and U-238.

Plutonium phase diagram

I have seen a three-dimensional version of the plutonium phase diagram that was even more striking that the two-dimensional one shown on this page. Check out figure 16 on page 23 in this PDF. The problem is that this particular version of the diagram seems to be owned by the Metallurgical Society. I wonder if someone would be able to get the data and recreate their own version of it? I don't know how to make 3-D charts of that nature and I don't know where to get the data. But it would be really neat to have one like it, since it really makes clear how different in size and volume the phases can be under different conditions. --Fastfission 22:52, 19 August 2006 (UTC)

Two problems with the article here: first the allotropes are quoted to have different density 'at the same volume' which makes no sense. Density is an intensive property which is a function of the pressure and temperature. Volume is an extensive propery which depends on how much plutonium you have. I think the correct statement, in line with the graph, is that the density difference between different allotropes is quoted at constant pressure. Also, the graph has an incorrect temperature axis - it should be just kelvin K rather than the incorrect 'degrees Kelvin' °K. I'm not sure how this could be corrected. --Tdent 16:48, 17 September 2006 (UTC)

"Plute"

'Nuclear materials workers sometimes call it "plute".' - does this really need to go in the very first paragraph? There are many interesting things to include in an encyclopedia article about plutonium, but a slang term used by workers doesn't really strike me as being one of them... Tpth 04:39, 31 August 2006 (UTC)

Agreed and removed. Femto 11:32, 31 August 2006 (UTC)
Cheers :) Tpth 23:49, 31 August 2006 (UTC)

Plutonium in fiction

Is that section appropriate? Man with two legs 15:36, 2 October 2006 (UTC)

Pu released in explosions

Is there any credible estimate of the amount of plutonium released sine 1945 in nuclear weapon tests? 10 tons is a convenient round number, and it would seem a bit too simple. Unless anyone has a link or a reference?Rolinator 06:34, 16 October 2006 (UTC)

7700kg, according to The Chemistry of Actinide and Transactinide Elements (page 1805). I changed the text but didn't add the reference. If you know how to do this, please do.
I am suspicious of that figure because it seems too precise. Several countries have carried out nuclear tests with yields not precisely known, so the amount of Pu released into the atmosphere can only be a guesstimate. Man with two legs 10:07, 30 November 2006 (UTC)
Sorry, the reference says, "[a] total of approximately 7700kg of plutonium has been released in atmospheric and underground nuclear explosions." It goes on to give an approximate breakdown by groups of countries (with citations). I ran across it while reading the book, and remembered that someone had asked the question, so I thought I'd add it since it comes from an authoritative but unclassified source. I added the word "approximately."
OK, now I am convinced! Man with two legs 17:11, 30 November 2006 (UTC)

change "Pu" from redirect to disambiguation

I would suggest that the entry "Pu" receives a "disambiguation site" rather than a simple redirect to this site. (Sorry, I don't know yet how to do that, otherwise I'd do it myself.) For "Pu" is the last name of the last ruling Chinese emperor--his name can either be spelt in one word (Puyi) or in two (Pu Yi). While there's already a redirect from "Pu Yi" to "Puyi", I'd suggest to add one from "Pu". --Ibn Battuta 06:02, 30 October 2006 (UTC)

References needed under the applications section

The following bit at the end of "applications" isn't sourced at all. Especially the LD50 ought to be properly sourced. Also the last sentence is quite loaded and uses weasel words and statements like "casts questions". 213.55.27.154 18:42, 31 March 2007 (UTC)

"The toxicity of plutonium is in dispute; nuclear industry advocates point to the low chemical toxicity of plutonium and ability of a worker to hold a kilogram brick of the material without protection; if inhaled or digested, however, plutonium's effects due to radioactivity overwhelm the effects of plutonium's chemical interactions with the body, and the LD50 dose drops to the order of 5ug/kg. The insistence on both sides of the issue of plutonium's safety/deadliness casts questions on the current habitability of areas that have been exposed to nuclear warfare and on the health of the current residents."

COST

Does anyone know the cost of Plutonium? (If you can buy it).. Just wondering for a science project. THANKS!

I'm pretty sure you can't buy it without some kind of academic credentials. It'd be pretty expensive in any case.--Elmorell 13:09, 21 April 2007 (UTC)

Esperium

Esperium redirects here. What is esperium named after? --Error 23:24, 3 February 2007 (UTC)

  • My bet is the thing is a hoax, now spreading across Wikipedia like Kudzu. I'm going to tag the redirect for deletion. I don't believe "esperium" has ever been a name for plutonium. SBHarris 01:56, 4 February 2007 (UTC)
In response to the original question, see first [1] under "Esperium, Hesperium"—apparently the element went by both of these names, though it carried the symbol Es. Then, for more history, see [2], under "Ausonium & Hesperium"—the element was named after Hesperius ("Italy, seen from Greece"). But it turned out that he hadn't discovered the element with atomic number 94; rather, it was a combination of other things. So the name didn't stand. --Spangineerws (háblame)

Heat given off

Here is a sentence from the article, "The heat given off by alpha particle emission makes plutonium warm to the touch in reasonable quantities; larger amounts can boil water." What isotope is the article referring to (more than one isotope decays by alpha particle emission)? There is a wide variation in the decay rate between isotopes, which suggests that the heat they generate would vary widely, as well. Also, if the article is referring to plutonium-239, boiling water seems unlikely because I have seen people handling plutonium pits with their bare hands. Finally, how much of the heat would come from the Pu-240 that Pu-239 is always somewhat contaminated with? Does anyone have a reference for the claim? -- Kjkolb 11:38, 24 February 2007 (UTC)

All good questions. All the isotopes decay by alpha emission. Ordinary weapons-grade Pu-239 in 6 kg size pits is (by accounts) 10 or 20 C warmer than ambient, and feels like a live animal to handle (so said the Manhattan people, and they weren't even handling super weapons grade stuff which is available today). The more Pu-240 it has in it, the thermally hotter it is, to the point that reactor-grade Pu pits (if you reprocess used fuel rods to try to make weapons) are VERY hot to the touch and hot enough to cause thermal problems in bombs and so on (they'd have to be actively cooled). But apparently a bomb can still be made from them. It might have to be a bomb with a lot of muffin fans in it, like your P4 computer <grin>. But do-able SBHarris 23:26, 5 March 2007 (UTC)
I'm not too sure about that. Heat isn't the only problem you know. Setting off the chain reaction too early causing a "fissle" is a greater problem. Seeing that this is sufficiently troublesome to make even weapons grade plutonium require the use of the implosion principle rather than a gun-triggered device would suggest that reactor grade plutonium, containing more than twice the amount of Pu-240 at the very least, would be very difficult to make a functional weapon out of, even ignoring the thermal problems. In any case it would probably be easier to make weapons grade Pu from scratch than trying to use reactor grade material. 213.55.27.154 18:36, 31 March 2007 (UTC)
Sorry, but Sbharris is wrong. Not all the isotopes decay by alpha emission. 238, 239, 240 and 242 do. 241 and 243 do not. As far as boiling water, a small 238 heat source containing PUO2 sits at approx 800C, plenty hot enough to boil water. Amounts of Pu in pits are classified, and the temperature will depend on what, if anything, is surrounding the pit. Bare Pu metal is corroded very quickly by water.

Plutonium-238 is the big one from a decay-heat point of view. It's used as the basis for the vast majority of modern Radioisotope Thermoelectric Generators. Boiling water with a large enough quantity of the material would certainly be a reality. AWeishaupt 11:26, 16 June 2007 (UTC)

Good article review

Hello. I've performed the Good Article Review, but must fail the article because it contains a large number of unreferenced facts.

The sections near the bottom - notably "Toxicity" - are not supported by references. Also, there are one or two "citation needed" tags which should be sorted, and the citations for the "Flammability" section no longer work

One or two other minor thoughts

  • The introduction says "The most important isotope of plutonium is 239Pu", but does not say how it is the most important.
  • The "External links" section needs to be improved and recuced.

If the references issue is sorted, I see no reason for it not to become a GA, and would support it for good or featured article status. --h2g2bob 19:08, 5 March 2007 (UTC)

I plan to work on the ref issue as well as a general expansion. When I'm done, I will submit directly to FAC. --mav 23:10, 5 March 2007 (UTC)

Important Vs Significant

I have always understood that something was 'important' because it had value as an intrinsic characteristic and that something was 'significant' if it had value assigned to it by an outside observer. Although the words are commonly used interchangably. In the sentance "The most important isotope of plutonium is 239Pu, with a half-life of 24,110 years." I think significant works better, as it only has value as we humans use it, not because of it's existance. Significant makes more senese to me for that reason. Starkrm 15:09, 22 March 2007 (UTC)

Both these are words relating to human judgement, so what's the difference? You're talking about popularity. Neither one is objective, as are attributes such as "common" or "stable".SBHarris 00:36, 23 March 2007 (UTC)
Both versions make sense to me, so I wouldn't have a problem with it being changed. --h2g2bob 23:10, 22 March 2007 (UTC)

Actually, I think both terms ARE objective, but I was thinking in terms of other isotopes of Pu. A scientist would hesitate to say the other isotopes are less-important, but would say they are less-significant. It's a subtle point and it doesn't really matter to me much, but I was trying to express why I changed the word, rather than just change it back. Starkrm 03:15, 23 March 2007 (UTC)

Went ahead and changed it. Starkrm 01:51, 5 May 2007 (UTC)

Toxicity Inconsistency

The two sections on toxicity seem to be inconsistent. Early in the article is a reference to 5 micrograms per kilogram causing an LD-50 dose of radiation, but later it says that plutonium is less toxic than caffeine, which is routinely taken in mg/kg doses. Is the latter the chemical toxicity and the former the physical / radiation toxicity? If so, these two should be better distinguished in the article. --Zack Subin (student at UC-Berkeley) 24.23.138.158 08:47, 19 April 2007 (UTC)

Professor Bernard Cohen, University of Pittsburgh, offered to test this (provided Ralph Nader took the caffeine!) because he believes that the Pu would pass through the alimentary tract and not be taken up. I realize I'm not really addressing your point, that this should be clearer in the article; it is there, but it could certainly be brought out more. --Old Moonraker 09:05, 19 April 2007 (UTC)


I removed the bit about using Plutonium in a radiological "dirty bomb" weapon.

Plutonium is not something that would normally be considered of relevance to a radiological bomb, compared to highly active beta and gamma emitters which are commonly used in industrial and technological applications. See the dirty bomb article for more information. Perhaps this idea stems from the myth of Plutonium's fantastically high radiotoxicity?AWeishaupt 11:24, 5 July 2007 (UTC)

Thanks for your efforts to remove nonsense. I think the myth of Pu's toxicity needs to be discussed in the article, but the article should not contribute to perpetuating the myth. However, regarding the "dirty bomb," I believe (this is WP:OR, mind you) that Pu-238 could be material for a dirty bomb. --orlady 14:27, 5 July 2007 (UTC)
Truth be told - a dirty bomb only needs to contain the possibility of any radiological material to cause the sort of panic necessary in order for it to be effective. The radiological consequence of a dirty bomb is much less significant than the psychological consequences. Starkrm 21:31, 5 July 2007 (UTC)

Heptavalent or octavalent?

PuO52- looks octavalent to me. It's eight elements from the noble gas radon so Pu(VIII) would be plausible, if maybe difficult to achieve in practice. I'll let someone else do the experimental verification! Dajwilkinson 00:11, 2 August 2007 (UTC)

Equals sign?

In the applications section we find

"The isotope plutonium-238 (238Pu) has a = half-life of 88 years"

Is the equals sign here a typo or a notation involved in half life that I haven't seen before? Molinari 00:22, 28 August 2007 (UTC)

It's a typo. --JWB 10:13, 28 August 2007 (UTC)

I propose that the "Plutonium in popular culture" be removed. It is simply a list of trivia, giving the appearances that plutonium has made in television shows, movies, books and videogames. Also, it is essentially impossible to reference. You just have to take the word of whoever adds an entry, as the appearances of plutonium in television shows do not usually generate books or articles in newspapers or magazines. To make matters worse, the people who add entries are often anonymous. This might be okay when references are used, but it is very questionable when they are not ("might" because a person can give fake references that cannot easily be found out, which is a problem with all contributions). In addition, the section offers no insights into the subject whatsoever. For these reasons, I do not think that such content is appropriate for an encyclopedia. If we were a popular culture or television site, then it might be appropriate. However, we are not such a site. -- Kjkolb 14:45, 30 August 2007 (UTC)

  • It is not inherently impossible to reference, although this particular section is currently unrefererenced.
  • There is a huge amount of popular culture and television material on Wikipedia. I would guess it is one of the most heavily covered subjects on Wikipedia.

--JWB 19:36, 30 August 2007 (UTC)