Talk:Polonium/Archive 1
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Archive 1 |
I added a bit about the naming of Polonium in the history section. Both her biography of Pierre and her dauther's biography of her specifically mention the naming of Polonium to cause attention to the plight of Poland, which was dominated by Russia and not recognized as a country. I bring it up because of some political controverys in the naming of new elements have come up, and I want to make it clear this is not new. It also links back to French attitudes towards her when a scandal broke out. [69.0.127.128]
I editied out erronius data that was entered stating that PO is not dangerous to humans. I assume this was vandalization after the news of the death of Alexander Litvinenko, who was found with PO 210 in his body. 00:12, 25 November 2006 (KST)
Citation from main page: Of the 18 passed on to the HPA, three will now be checked for contamination by Polonium 210, the highly radioactive element believed to have killed the former agent who died at University College Hospital last week. end cit. Will we have to edit that every week, from now? Install a week counter? w.
Current event?
I removed the current event tag once, and it got re-added, and I can't find who did it to ask the user why. I don't think it should be there, since Polonium is NOT a current event. The poisoning is the event. Information on Polonium isn't going to 'change rapidly'. Maybe if the year was in the late 1800s that would make sense. Dancraggs 01:19, 28 November 2006 (UTC)
Disputed
The article states, "The great radioactivity of polonium and its immediate neighbors to the right on the periodic table, and its stark contrast with lead and bismuth, is due to the great instability of nuclei containing 84 or more protons, especially when they also contain 128 neutrons, which causes them to be extremely unstable and rapidly emit alpha particles." However, lead 210 is an isotope with 128 neutrons, and it is primarily a beta emmiter (with some alpha emmition) with a half life of 22.3 years (source). This contradicts the statement that nuclei with a neutron number of 128 are all very unstable alpha emmiters. Polonium 12:26, 2 April 2006 (UTC)
-- below: perhaps "proton rich isotopes" should be "neutron rich isotopes" since isotopes differ by number of Neutrons not Protons. -eb.
Synthesis by (p,n) and (p,2n) reactions It has been found that by proton bombardment of bismuth using a cyclotron that the longer lived isotopes of polonium can be formed. Other more proton rich isotopes can be formed by the irradation of platinium with carbon nuclei.[8]
Irksome
Po is very nasty, it has an ability to go through glovebox gloves and get into the air. As I understand it, it is worse even than Pu-238. For those who do not know it, if you put a lump of Pu-239 as the sintered dioxide in a glove box or even on your desk (then leave it for a week) then the alpha contamination near will be next to nothing. Do the same thing with Pu-238 and the whole of the inside of the box will be all be active. Po can do the same thing, but it has an even worse reputation than Pu-238.Cadmium
- I was not disputing that it is nasty stuff, simply that 'irksome' is a subjective word, and as such should be replaced with something else in an encyclopedia article which should be objective. StealthFox 23:04, 14 May 2006 (UTC)
Contradiction
The fatuous comment is made that "what is remarkable is that it poses no risk whatsoever to anyone", whereas a bit later the statement is made that it is highly toxic. Would someone please correct these statements with a proper reference?
Alexander Litvinenko
It has been announced that Alexander Litvinenko was killed by a "major dose" of Polonium 210. [1] --jmb 15:40, 24 November 2006 (UTC)
- The Metropolitan Police and Health Protection Agency appear to being careful not to say that he was poisoned, they say that they are looking for the source of the Polonium 210. [[2]] [[3]]--jmb 17:02, 24 November 2006 (UTC)
The article states the FSB poisoned Litvinenko. Either the author of that portion of the article broke a major conspiracy, forgot/failed to cite sources, or it does not belong in Wikipedia whatsoever. (Edit: now says Litvinenko blamed the FSB, which is proper, as a note dictated by Litvinenko directly implied that).
- To even things out, shouldn't it be stated that both Putin and FSB had officially denied any involvement?
Why is it even necessary to mention in this article, "Traces of polonium were found in several locations he had visited shortly before becoming ill. [2] Litvinenko on his deathbed blamed his death on deliberate poisoning by the FSB (the successor organization of the KGB) and ultimately Russian President Vladimir Putin. [3]" This paragraph is not about Polonium, but about the who poisoned Alexander Litvinenko and should be moved.Bladeofgrass 11:23, 25 November 2006 (UTC)
The added comment "Putin loves it." Cute comment. Good to have a little humour now and then, even though the link is only suspected to my understanding. Given the purpose of Wikipedia, in time it should go. In the longer term, my thought is a link re a famous suspected or confirmed case of poisoning by Po of Alexander Litvinenkoto be added to this article. I mean this with no disrespect to Alexander's death. Historically significant speculations and established facts can be recorded there.
Returning to humour. There is a role for humour in any serious endeavour! The right dash in my view helps quality outcomes. CofE001 00:14, 26 November 2006 (UTC)
- I am making the following change: The article says Litvinenko was "allegedly poisoned" by 210PO. This isn't factual. He was most certainly poisoned by 210PO, that is a fact. He was allegedly murdered by poisoning. 24.219.97.39 22:47, 27 November 2006 (UTC)
It was also found on more than one plane. Doubtful that more than one KBG guy was sent to nuke him. Likely a smuggling ring playing with some nasty stuff, anyone from Russia who met with Litvinenko is probably staring at some bright lights in a basement right now.
I really cant figure how traces of this substance might be left on a 'plane which has been used to carry it, unless the substance was in a very insecure comtainer, or someone was deliberately leaving traces. Laurel Bush 17:12, 30 November 2006 (UTC).
We should need to semi-protect the article about polonium, because unregistered users have given a "major dose" of vandalism and page blanking since Alexander Litvinenko was poisoned with Polonium 210. 86.101.211.226 19:54, 8 December 2006 (UTC)
- agree with above user, more of a intrest into why it killed him? —The preceding unsigned comment was added by Krishan sood (talk • contribs) 16:01, 10 December 2006 (UTC).
Polonium in Cigarettes
Polonium is studied in a few nuclear research laboratories where its high radioactivity as an alpha-emitter requires special handling techniques and precautions.
Polonium -210 is the only component of cigarette smoke that has produced cancers by itself in laboratory animals by inhalation - tumors appear at a level five times lower than the dose to a heavy smoker.
Lung cancer rates among men kept climbing from a rarity in 1930 (4/100,000 per year) to the No. 1 cancer killer in 1980 (72/100,000) in spite of an almost 20 percent reduction in smoking. But during the same period, the level of polonium -210 in American tobacco had tripled. This coincided with the increase in the use of phosphate fertilizers by tobacco growers - calcium phosphate ore accumulates uranium and slowly releases radon gas.
As radon decays, its electrically charged daughter products attach themselves to dust particles, which adhere to the sticky hairs on the underside of tobacco leaves. This leaves a deposit of radioactive polonium and lead on the leaves. Then, the intense localized heat in the burning tip of a cigarette volatilizes the radioactive metals. While cigarette filters can trap chemical carcinogens, they are ineffective against radioactive vapors.
The lungs of a chronic smoker end up with a radioactive lining in a concentration much higher than from residential radon. These particles emit radiation. Smoking two packs of cigarettes a day imparts a radiation dose by alpha particles of about 1,300 millirem per year. For comparison, the annual radiation dose to the average American from inhaled radon is 200 mrem. However, the radiation dose at the radon "action level" of 4 pCi/L is roughly equivalent to smoking 10 cigarettes a day.
In addition, polunium-210 is soluble and is circulated through the body to every tissue and cell in levels much higher than from residential radon. The proof is that it can be found in the blood and urine of smokers. The circulating polonium -210 causes genetic damage and early death from diseases reminiscent of early radiological pioneers: liver and bladder cancer, stomach ulcer, leukemia, cirrhosis of liver, and cardiovascular diseases.
The Surgeon General C. Everett Koop stated that radioactivity, rather than tar, accounts for at least 90% of all smoking-related lung cancers. The Center for Disease Control concluded "People are exposed to far more radiation from tobacco smoke than from any other source."
Cigarette smoking accounts for 30% of all cancer deaths. Only poor diet rivals tobacco smoke as a cause of cancer in the U.S., causing a comparable number of fatalities each year. However, the National Cancer Institute, with an annual budget of $500 million, has no active funding for research of radiation from smoking or residential radon as a cause of lung cancer, presumably, to protect the public from undue fears of radiation.
If the average American knew how many pCi's of polonium he/she/baby had in their system they would faint - nonsmokers have less but still a surprising amount. ( Carrots,etc are grown with the same fertilizer components as tobacco. ) Greatgranddady smoked and didn't get cancer, greatgrandma didn't smoke and didn't get cancer - now all bets are off ( only arguing whether you are less or more likely and which type would you rather get ). I hope someone is making good money off this - and I hope he smokes 4 packs a day.
Availability of Polonium
You can't just buy a milligram of Polonium on e-bay or repeat the Curies' experiment in your basement. Is Polonium availability restricted to governments, or is it also available in University research labs or hospitals? It seems like such a dangerous element should be strictly controlled. Also, is it possible to trace a particular sample of Polonium to its source based on trace amounts of contaminants?
- You can buy it right here (if you are in the US). --startaq 23:33, 24 November 2006 (UTC)
- That website seems a little questionable...so anyone can buy radioactive substances without any license? Jumping cheese
Cont@ct 11:49, 26 November 2006 (UTC)
- That outfit, United Nuclear Scientific Supplies, is a real reagent supplier for backyard experimenters. They are occasionally in a bit of hot water, but mainly about the pyrotechnics, not the radioactivity. Note that their polonium-210 product is 0.1 microcuries, less than 1/5000 of the 525 microcurie lethal dose discussed in the article. Even United Nuclear (or their "NRC licenced isotope manufacturer") would probably ask some questions if someone told them they'd like 10,000 of those, please... --mglg(talk) 23:00, 26 November 2006 (UTC)
- Staticmaster brushes have hundreds of microcuries of Po [4]. Thanks for the info re Po decay. 67.117.130.181 01:39, 27 November 2006 (UTC)
- Looks like General Electric is the original source of the Po-210 "Static Eliminators". The picture shows it to be similar to the "Staticmaster" device. This part is available by mail order. See details below:
- Staticmaster brushes have hundreds of microcuries of Po [4]. Thanks for the info re Po decay. 67.117.130.181 01:39, 27 November 2006 (UTC)
- That outfit, United Nuclear Scientific Supplies, is a real reagent supplier for backyard experimenters. They are occasionally in a bit of hot water, but mainly about the pyrotechnics, not the radioactivity. Note that their polonium-210 product is 0.1 microcuries, less than 1/5000 of the 525 microcurie lethal dose discussed in the article. Even United Nuclear (or their "NRC licenced isotope manufacturer") would probably ask some questions if someone told them they'd like 10,000 of those, please... --mglg(talk) 23:00, 26 November 2006 (UTC)
- That website seems a little questionable...so anyone can buy radioactive substances without any license? Jumping cheese
GE Static Eliminator for PCTE (99080)
- Polonium 210 encased in stainless steel housings
- 500 microcuries
- Part # 1215174
- Model # STATIC0001
- Price: US $71.00 [5]
Who ever got ahold of the isotope would probably get it from a nuclear reactor or a nuclear accelerator.
Forget about industrial use of Polonium in antistatic agents.
Judging from my reading of some Internet open sources it looks like, that Polonium is particularly interesting for the military.
http://en.wiki.x.io/wiki/Nuclear_waste mentions Po in connection of dismantling nuclear weapons - either as a trigger substance or as a source of energy for nuclear rockets (to generate heat and electricity - the same way as it was used by Russian Lunochod).
I am not an expert chemist or nuclear chemist, but can anyone write more about it?
Plagiarism in section Precautions
The following two paragraphs under the section Polonium#Precautions are lifted from a listed external link almost word for word:
Polonium is a highly radioactive and toxic element and is dangerous to handle. Even in milligram or microgram amounts, handling polonium-210 is very dangerous and requires special equipment used with strict procedures. Direct damage occurs from energy absorption into tissues from alpha particles.
The maximum allowable body burden for ingested polonium is only 1100 becquerels (0.03 microcurie), which is equivalent to a particle weighing only 6.8 × 10-12 gram. Weight for weight polonium is approximately 2.5 × 1011 times as toxic as hydrogen cyanide. The maximum permissible concentration for airborne soluble polonium compounds is about 7,500 Bq/m3 (2 × 10-11 µCi/cm3).
--Liulk 03:50, 25 November 2006 (UTC)
- Might be a bit of a problem given that this doesn't appear to be in the public domain [6]. Nil Einne 16:31, 25 November 2006 (UTC)
BTW, today's NY Times article gives the figure for toxicity as 250 million times more toxic than cyanide. I assume the LANL figure is correct, and the NYT reporter just made a mistake in converting.--24.52.254.62 16:49, 25 November 2006 (UTC)
Dose due to internal Po
The commited dose due to intermal Po, is that a dose commitment over many years or over a shorter time. I think that the editor who made that addition should make it more clear.Cadmium
Typo
the successor oranization of the KGB -> organization
Solid State Form
The current page states:
The alpha form of the Po solid is cubic (Po-Po distance is 3.352 Å), it is a simple cubic solid which is not interpenetrated. A myth has grown up from a single sentence in one of the original papers on the crystal structure as determined by X-ray powder diffraction. Below is a diagram of a triple interpenetrated cubic solid, while for Po this is not the structure a reasonable number of real examples of such an interlocking network have been found.
This is very confusing. First, what is the myth? It sounds as if the myth were that Polonium's crystal structure is interpenetrated, but that's not at all clear. Second, the third sentence's structure is very convoluted.
Assuming I understand the myth, I'd suggest changing this to the following:
The alpha form of Po is a simple cubic solid (Po-Po distance is 3.352 Å). There is a myth that Polonium's crystal structure is interpenetrated, arising from a single sentence in one of the original papers on the crystal structure as determined by X-ray powder diffraction. Below is a diagram of a triple interpenetrated cubic solid; while this is not the crystal structure of Po, real examples of such an interlocking network have been found.
If I'm right, would someone who can confirm this make this change? Dtgriscom
- Yes you have got it right.Cadmium
Power output of Polonium 210
Until a few days ago the article stated that the power output of 1g of Po 210 was 140W. This was changed to 150W by 84.190.155.226 with no explanation (AFAIK). Other references (excluding news sites which may well have taken their figure from wikipedia) state 140W nuenergy.org, jlab.org, while globalsecurity.org states that the power output is 120W/g.
My rough and ready calculation came to 138W, so I am wondering why it was changed and what data is being referenced to support this change? Gloop 15:12, 25 November 2006 (UTC)
- Probably either a mistake or sneaky vandalism. I suggest you change it back given the evidence to the contrary Nil Einne 16:33, 25 November 2006 (UTC)
I get 144 watts, so maybe there was just some rounding issue based on slightly different approximations. My calculation (please check it) went: the half-life H is 138.376 days or 138.376*86400 seconds. The amount remaining in a sample after T seconds is 2**-(T/H) so the amount that's decayed after 1 second is 1-2**(1/H) = 5.797e-8 of the starting sample. For 1 gram, since the atomic weight is 210, the number of atoms is 6.022e23/210 = 2.8676e21. So the number of decays per second is 5.797e-8*2.8676e21 = 1.6625e14. The energy per decay is 5.407 MeV or 8.663e-13 joules. Multiply by the number of decays per second and you get power in watts, 144.025 watts.
Wrong year of discovery
The article states that Polonium was discovered in 1897, while Encyclopædia Britannica and numerous other sources state it was discovered in 1898. Please fix this. 85.157.76.171 18:01, 25 November 2006 (UTC)
- Is there a cite other than EB?
- Pfützner M. (1999). "Borders of the Nuclear World --- 100 Years After Discovery of Polonium". Acta Physica Polonica B. 30: 1197.
{{cite journal}}
: Text "issue 5" ignored (help) schould state the date for the discovery --Stone 10:16, 28 November 2006 (UTC)- Kabzinska K. (1998). "Chemical and Polish aspects of polonium and radium discovery". Przemysl Chemiczy. 77: 104–107.
{{cite journal}}
: Text "issue 3" ignored (help)
- Kabzinska K. (1998). "Chemical and Polish aspects of polonium and radium discovery". Przemysl Chemiczy. 77: 104–107.
- Pfützner M. (1999). "Borders of the Nuclear World --- 100 Years After Discovery of Polonium". Acta Physica Polonica B. 30: 1197.
- Adloff J. P. (681–688). "The centennial of the 1903 Nobel Prize for physics". Radichimica Acta. 91: 2003.
{{cite journal}}
: Text "issue 12" ignored (help)CS1 maint: date format (link) or even better here.
--Stone 10:26, 28 November 2006 (UTC)
One of the articles above states: P. and M. Curie announced the discovery of polonium in July 1898. Curie P., Curie M. (1898). Comptes Rendus. 126: 1101. {{cite journal}}
: Missing or empty |title=
(help)
Polonium in Fiction
Is this really wikipedia-worthy?
- A precedence for such entries has been established under the wiki entry "Radiation Poisoning".
- Then maybe it should be moved to that article. Bladeofgrass 19:07, 25 November 2006 (UTC)
- Moved to fictional applications of real materials. Femto 19:16, 25 November 2006 (UTC)
- As the originator of the "Polonium in Fiction" modification, I think the above change is an improvement. Thanks.
- Moved to fictional applications of real materials. Femto 19:16, 25 November 2006 (UTC)
- Then maybe it should be moved to that article. Bladeofgrass 19:07, 25 November 2006 (UTC)
Why the protect?
Why has this article been semi-protected? It wouldn't seem like a high-risk article for vandalism. Alethiophile123 23:16, 25 November 2006 (UTC)
- Almost certainly because of the Litinvenko incident, which is current. Bryson430 19:16, 26 November 2006 (UTC)
lethal dose calculation
The lethal dose calculation has gotten messed up since last night. The errors in the current version should be pretty obvious to anyone up to the task of fixing them. 67.117.130.181 22:15, 26 November 2006 (UTC)
- -- I've now attempted a fix, could someone please check it. 67.117.130.181 02:10, 27 November 2006 (UTC)
- --Is it valid to use committed effective dose equivalent (CEDE) to calculate the dose required for death from acute radiation syndrome? I thought the CEDE was used to estimate long-term cancer risk with relatively low doses, not acute effects from high doses. Acute radiation syndrome typically requires a whole-body dose (or close to whole body). It is presumably harder to achieve a whole-body dose with an alpha emitter like polonium-210 because the alpha particles don't penetrate far.
radiation question
Can someone explain how this radiation thing works in terms of where the particles go? I.e. suppose you have a 1 foot diameter Po-210 sphere. The polonium in the interior of the sphere decays into helium nuclei and some other decay products (lead?). I gather that through some kind of nuclear process, the lead left over after a Po atom has ejected two protons in the alpha particle, somehow creates two new electrons to stay electrically neutral. But where do the helium nuclei go? They don't penetrate to the outside of the sphere. Do they stay inside, like a dissolved gas or something? Does the sphere take on a net positive charge? Also, where does polonium-210 come from in nature (i.e. in uranium ore)? Some kind of decay product from the uranium? That should be mentioned in the article. The po-210 half-life is far too short for any to be left from when the uranium itself was first made in some zillion year old supernova. 67.117.130.181 22:38, 26 November 2006 (UTC)
- Questions like that should really be directed to the Science Reference Desk, but here goes: Yes, the decay product from alpha-decay of polonium is lead. No, the post-decay nucleaus doesn't create two new electrons, to the contrary it ejects two of those it had (it lost positive charge in the alphaparticle, so it needs to lose negative charge to compensate). Yes, the alpha-particles (helium nuclei) emitted in the interior of the sphere would get trapped there, or at most be able to diffuse around slowly. Since solid polonium is electrically conducting, the ejected electrons would be able to travel freely through the sphere, and would be attracted to the positively charged helium nuclei and combine with them into neutral helium atoms. (Alpha-decay, by the way, is the process by which all the helium we use in balloons and MRI magnets was formed, deep in the Earth - a very slow process, which is why we won't get any more helium once we've wasted what we have.) The sphere would thus not take on any net charge of either sign. As you point out, polonium (all isotopes of it) has far too short half life for any significant amount to be still around from the formation of the Earth. That polonium is still present on Earth, in minute amounts, is only because it is continally being produced by radioactive decay of more long-lived radioisotopes. In particular, polonium-210 is the second-to-last step in a 14-step decay series by which uranium-238 turns into lead-206. U-238 itself has a half-life of 4.5 billion years, and is therefore still around from that "zillion year old supernova" of yours. --mglg(talk) 00:36, 27 November 2006 (UTC)
- I would agree with mglg, if you were to consider a uranium dioxide nuclear fuel the you should be aware of the fact that some of the fission products are gases. It is normal in used fuel to find that some of the xenon has moved around and has then formed microscopic bubbles which remain in the fuel. Even while the fuel is very hot the gas remains in the solid, on heating up to a temperture far in excess of the operating temperture the gas is released. So I would assume that the helium in a small lump of Po might form some small bubbles if it migrates to where a defect in the solid is, the helium in the bubbles would remain there for a long time unless the solid was crushed and heated. You should be aware that a large lump of Po is likely to heat up a lot so the helium would be lost more quickly, I think that a 30 cm diamater Po-210 sphere would melt due to the self heating. The longer lived Po isotopes would heat up less however.Cadmium
Sources
Most of the article references in the body of the text should be moved to footnotes. Furthermore, many of the facts presented lack any sort of credible reference. --209.189.245.112 13:55, 27 November 2006 (UTC)
References
- Radford Jr. E. P., Hunt V. R. (1964). "Polonium-210: A Volatile Radioelement in Cigarettes". Science. 143 (3603): 247–249. doi:10.1126/science.143.3603.247.
- Bangnall K. W. (1962). "The Chemistry of Polonium". Advances in Inorganic Chemistry. 4: 197–229.--Stone 09:55, 28 November 2006 (UTC)
- Rencováa J., Svoboda V., Holuša R., Volf V., Jones M. M., Singh P. K. (1997). "Reduction of subacute lethal radiotoxicity of polonium-210 in rats by chelating agents". International Journal of Radiation Biology. 72 (3): 247–249. doi:10.1080/095530097143338.
{{cite journal}}
: CS1 maint: multiple names: authors list (link) - Rencová J., Vlková A., Čuřík R., Holuša R., Veselá G. (2004). "Influence of heavy metals upon the retention and mobilization of polonium-210 in rats". International Journal of Radiation Biology. 80 (10): 769–776. doi:10.1080/09553000400017911.
{{cite journal}}
: CS1 maint: multiple names: authors list (link)
superscripts
Can we retain the proper superscripts for isotope references? The entire reason why 210Po exists is to prevent the tedious re-re-re-use of things like "Polonium-210" in (for example) encyclopedia articles on the subject. mdf 14:16, 28 November 2006 (UTC)
I have flipped a few isotope references back to the 238U (etc) forms to be consistent with the rest of the article. mdf 23:33, 29 November 2006 (UTC)
Nevermind. Life is simpler when you just stop caring... mdf 00:06, 30 November 2006 (UTC)
Litvinenko
Do we really need to reference this subject here? Why not directly reference polonium at the article on Litvinenko, leaving this article to describe the physical substance? At best, an entry in "See also" is all that is needed here. mdf 14:19, 28 November 2006 (UTC)
page protection
Is the page protection really needed? There was repeated vandalism from just one IP, which is now blocked. The person came back under another IP and made just one edit. I think it's better to block that IP if the person comes back, than protect the page. There are several IP's trying to edit the article legitimately and the protection is in the way. 67.117.130.181 08:32, 29 November 2006 (UTC)
- Whilst this is connected to a current news item, it may be best to keep that semi-protection. -- Beardo 06:45, 30 November 2006 (UTC)
- I don't think that's sufficient reason for semi-protection, which is supposed to be reserved for situations where reverting and blocking vandals is too big a pain, or for certain obscure biographies (not applicable to this article). See WP:SEMI. This page shouldn't really be protected, there seems to have been just one recent vandal, who has been blocked. 67.117.130.181 11:44, 30 November 2006 (UTC)
fatal rat dose
I calculate that the fatal rat dose is 8.72e-9 grams per kg of body weight, based on the 1.45e6 Bq/gm figure in the article. Can someone check the figure and then add it to the article? I can't add through the current article protection. Could also note that for a 100 kg human that would be 145e6 Bq or 0.039 curies, about 8e-7 grams of po210.
"See also Poisons" useful ?
Since 1) Polonium has a section on "Toxicity", 2) the WP article on Poisons does not mention polonium, and 3) the specific poisoning of Alexander Litvinenko has its own WP entry, I am wondering if the section "See also Poisons" is useful for polonium. Lklundin 12:27, 29 November 2006 (UTC)
- Arguably not, which is why I just removed it. mdf 12:44, 29 November 2006 (UTC)
Minor Edit
In section 210Polonium, "measureing" (sic) corrected to read "measuring". Joegee 18:41, 29 November 2006 (UTC)
Tests
Wouldn't that material be better in the gamma/alpha spectroscopy articles? mdf 23:37, 29 November 2006 (UTC)
Minor Edit
Someone, please fix the misspelled word "platinium" in the middle of the article. I'd do it but the article is in NaziMode(tm) right now and won't let me do my community part. Please delete this afterwards. Thanks ^_^
Could someone please add a few simple lines to the Polonium "Toxic" area, "repacking" the scientific data into a form that everyone else can understand ? Does it take a teaspoon of Polonium to kill a person ? A grain-of-sand sized piece ?
What if terrorists dumped a gallon of it into a City Water resevoir ? The science is nice and all, but it has a purpose other than itself and those that understand it. This stuff is scary and what people really want to know is can we be killed by small amounts of stuff that can be manufactured by any 3rd-world country with a nuclear reactor and a pack of kooks for a government.
Thanks, 64.148.244.230 05:02, 30 November 2006 (UTC)Johnny Faster
Figures are inconsistent
"The maximum allowable body burden for ingested polonium is only 1,100 becquerels (0.03 microcurie), which is equivalent to a particle weighing only gram"
half-life: 138.376 days
The 4.59 picogram contradicts the 6.8 picogram figure from the article. I'm not sure what figure is wrong, so I haven't corrected this. A1kmm 06:34, 30 November 2006 (UTC)
Spectra
I think if we're going to have THREE plots illustrating the attenuated alpha particle spectra from some radioisotopes we should at least make them accurate. The alpha emission energy of an isotope is narrow, as correctly shown by the one graph with sharp peaks, but the broadening of the peaks due to the passage of some of the alphas through a material is not a perfect gaussian around the original peak (like doppler broadening for instance)! The passage of the alphas through a material can not INCREASE their energy, only decrease. So what we SHOULD see is an exponentially decreasing curve toward the lower range of the spectrum with a sharp cutoff at the original emission energy. a cutoff peak. just like beta decays. --Deglr6328 07:44, 30 November 2006 (UTC)
- Having three plots seems to be excessive – I've been bold and removed the two broader ones. The text explains that the sharp peaks (as shown) will be broadened (in some fashion) in real lab conditions. Also rearranged the graphics, hopefully, to avoid splitting up the titles too much. -- MightyWarrior 10:54, 30 November 2006 (UTC)
- Dear Deglr6328, you are right about the passage of alphas through solid films. I have added the text to explain the broadening that can be seen in liquid sintillation where random events cause a variation in the number of photons detected per decay. Do you know some maths which would give a better approxiation to the shape of the spectra than the gaussian function ?Cadmium
- I'm afraid I do not know the function that would describe the shape of the spectrum we are looking for.--Deglr6328 09:03, 1 December 2006 (UTC)
Weighted words?
Under applications of polonium it says, "Killling (former) spies." This seems a bit emotionally charged. If that is to be listed as an application of polonium (which seems reasonable enough) I think it would be better listed under the more neutral wording "assassination."
minor edit 210Po
"A few curies (1 curie equals 37 gigabecquerels) of 210Po emit a blue glow which is caused by excitation of surrounding air." Not necessary to specify an amount. "excitation of electrons of surrounding air" may sound better than what is written. "A single gram of 210Po generates 140 watts of power." I would specify "thermic power" otherwise someone dumb will think it is electricity. Make wiki brackets around "microcuries" "The majority of the time 210Po decays only by emission of an alpha particle, not by emission of an alpha particle and a gamma ray." which means that the nucleus that results from the decay is not excited. I don't know, if that should be mentioned. 80.109.194.224 18:11, 30 November 2006 (UTC)
(It should be noted, that there no such word as "sintillation" in English - the proper term is "Scintillation". Dr. M. Kharatishcili.)
Trivia : Exam
Our professor included an exerpt from this article. Was a fun test. We had to work out the mass it would take to kill 1 st russian ex-spies. PoorLeno 20:17, 2 December 2006 (UTC)
Decays to ...
84-2=82 Thallium, presumably. The Litvinenko article seems bogged down in 210Po becoming Lead, which presumably Thallium eventually does, but not soon. Worth adding that to the article? Midgley 00:42, 4 December 2006 (UTC)
- Not worth adding, because it is incorrect. Atomic number 82 is lead. Thallium is 81. --mglg(talk) 02:29, 4 December 2006 (UTC)
Inaccuracy?
"A milligram of 210Po emits as many alpha particles per second as 5 grams of 226Ra." When I do a little math, I get about 4.215 grams of radium-226 for every milligram of polonium-210. I'm not an expert in radiation, since that unit was awhile ago in chemistry, so if somebody wants to check my work, go right ahead.
Half life is 1602 years, 584730 days for radium 226. Half life is 138.376 days for polonium 210.
for radium, 584730 = ln(2)/k
k = ln(2)/584730 = 1.18541409*10^-6
for polonium, 138.376 = ln(2)/k
k = ln(2)/138.376 = .0050091575
for radium, ln(A) = -k*1 + ln(1) after one day, starting at 1 gram
e^(-(1.18541409*10^-6)*1 + ln(1))
A = .9999988146 grams left after one day
for polonium,
e^(-.0050091575)*1 + ln(1))
A = .9950033674 grams left after one day
Out of one gram at the beginning,
in one day, 1.18541336*10^-6 g reacts in radium
in one day, .0049966326 g reacts in polonium
(.0049966326 grams polonium per day/ 1.18541336*10^.6 grams radium per day) = (x grams polonium per day/ 1 gram radium per day)
x = 4215.097263 grams Po per day for every 1 gram Ra per day react, units cancel, Po is 4215.097263 times more radioactive.
For the same level of radioactivity, 4215.097263 grams of radium must react for every 1 gram of polonium.
(1 gram Po / 4215.097263 gram Ra) = (.001 grams Po / x grams Ra)
To have equivalent levels of radiation, 4.215097263 (4.215 when rounded to significant figures) grams of radium must react for every one milligram of polonium. BirdValiant 05:45, 31 March 2007 (UTC)
- Your calculations look correct, but I think you are forgetting something. From the half-life numbers, it is true that, in one second, 4215 times as many nuclei of Po-210 decay as of Ra-226. However, you also need to account for the fact that Ra-226 nuclei are heavier than Po-210 ones by a factor of approximately 226/210. Thus, the activity from one milligram of polonium corresponds to that of 4215 * 226/210 mg = 4.536 g of radium. Rounded to one significant digit (as seems appropriate for illustration purposes), that does indeed come to 5 g. I'm changing the article back, unless someone finds a further flaw in the above. Hqb 11:25, 19 August 2007 (UTC)
LD50
The toxicity information seems inconsistent to me. LD50 doses are normally in mg per kg body weight, as is the Sv unit (equivalent absorbed energy per kg of tissue). But the article currently reads:
The fatal dose (LD50...) for acute radiation exposure is generally about 4 Sv [21]. One Bq of 210Po ... causes a radiation dose of 0.51 µSv if ingested, and 2.5 µSv if inhaled [22]. ...a fatal 4-Sv dose can be caused by ingesting 8 MBq (200 microcurie), about 50 nanograms (ng), or inhaling 1.6 MBq (40 microcurie), about 10 ng.
I can't make sense of this. An absolute amount of radiation (I mean radioactive substance) in Bq is translated into a dose per unit of body weight (Sv), which is then translated into an absolute toxic amount (50 ng). I'm not changing the article since I might be misunderstanding something here and I suppose there are plenty of knowledgeable people reading this article these days. Han-Kwang 23:01, 1 December 2006 (UTC)
- Here's the logic: (a) One Bq is not an amount of radiation, it is a quantity of a radioactive material that produces on average one decay per second. For any particular substance, activity in Bq is directly convertible to mass in grams; for 210Po the conversion constant is 166 TBq per gram, according to ref 22. (b) Activity in Bq is related to dose in Sv through an empirical number called the the "committed effective dose eqivalent" (CEDE), which is the amount of damaging radiation exposure in Sv that would be caused to a typical human by ingesting/inhaling one Bq of the substance. As I understand it, the CEDE takes into account how long it takes for human kidneys to expel the substance, how it distributes among organs, and how sensitive each of these organs is, as well as the type and energy of radiation. For ingestion of 210Po, the CEDE is 5.14E-7 Sv/Bq, according to the same ref. I tried to avoid introducing the concept of CEDE, to keep the text simple; was this a mistake?
- Anyway, this calculation was my own, and I'll readily volunteer that it should be criticized as original research because it combines information from different sources to draw conclusions. Thus it would be preferable to find a single source, of comparable reliability to the original sources here, that already contains the acute human LD50 in grams etc. That may be hard to come by, however (any volunteers for human LD50 experiments?), and rats/mice may get a lower radiation dose per ingested amount by excreting it much faster than humans, so using only rat/mouse data is not necessarily an improvement. Here is a place to look up the mouse LD50, though: "The toxicity of polonium 210 in mice. I. The thirty day LD50, retention, and distribution." FINKEL MP, NORRIS WP, KISIELESKI WE, HIRSCH GM. (1953), Am J Roentgenol Radium Ther Nucl Med. 70(3):477-85. PMID: 13080529. (Note that the same calculation as I did has since popped up in several places on the web, including an expert media advisory so don't use web sources younger than Nov 29 - they may have read it on Wikipedia...)
- By the way, I'm removing the existing rat toxicity reference (Rencováa et al.): the dose taken from that reference (8.7 ng/kg) was fatal to all 44 rats in that experiment, thus it does not represent the LD50 at all, but a much higher and more fatal dose. It is only an upper bound on the LD50, and thus not informative enough to quote here. --mglg(talk) 03:47, 4 December 2006 (UTC)
- Ah, with the CEDE it makes much more sense. I'm personally not very picky regarding original research, as long as the reasoning is verifiable. Han-Kwang 21:25, 5 December 2006 (UTC
I am only a radiation biologist and not a specialist in radiation toxicology, but I am pretty sure that the calculation of the amount of polonium which you need to cause a fatal dose leads you to a figure of mass in gram or nanogram and NOT in nanogram "per kg body weight". This "per kg body weight" is only used for chemicals. See also, http://www.mathed.tw/wd2/schoolwiki/wp/p/Polonium.htm, where they calculate 0.12 microgram for a lethal dose of 10 Sv. The mean lethal dose of 4.5 Sv (and that should perhaps also be said in your article) is a dose which causes 50% lethality, i.e. of 100 people exposed to 4.5 Sv, 50 will die. Further, you need to clarify the "minimal lethal dose" at the end of the paragraph. I suspect it is a mean lethal dose for non-instantaneous exposure, but then it should be 0.089 microgram (NOT 0.89), about 1.7 times more than the 50 nanogram in the instantaneous case. I do not know where your reference 29 has it from, and I cannot find anything like it in your reference 30. Tsp110 (talk) 12:56, 10 January 2008 (UTC)
Industrial alternatives
The article does a great job of explaining that industrial alternatives are readily available, to avoid using this dangerous substance merely to supress static electricity. Too good! The reader would tend to not notice that nonetheless Po-210 is in wide use for such trivial purposes, with no current measures to restrict/phase out. Can someone come up with some real facts and figures about annual industrial use? See The Smoky Bomb Threat by Peter D. Zimmerman NYT December 19, 2006 http://www.nytimes.com/2006/12/19/opinion/19zimmerman.html 69.87.193.121 15:00, 19 December 2006 (UTC)
tobaccodocuments.org has several documents on the occurence of polonium in the food & tobacco pipeline. The industrial alternative for polonium rich fertilizer - used a few decades before lung cancer was first seen by our family doctors ( it was so rare that med students used to travel to neighboring hospitals to see what was probably going to be the only case they would ever see ) - of course is polonium free fertilizer ( took a million PHDs and $billion to figure this out ).159.105.80.141 (talk) 20:27, 22 February 2008 (UTC)
Commercial sources of Polonium
Text says "Potentially lethal amounts of polonium are present in anti-static brushes sold to photographers.[55] Many of the devices are available by mail order. General Electric markets a static eliminator module with 500 microcuries (20 MBq), roughly 2.5 times the lethal dose of 210Po if 100%-ingested, for US $71;[56] Staticmaster sells replacement units with the same amount (500 mCi) of 210Po for $36.[57] In USA, the devices with no more than 500 mCi of (sealed) 210Po per unit can be bought in any amount under a "general license" [4] which means that a buyer needn't be registered by any authorities: the general license "is effective without the filing of an application with the Commission or the issuance of a licensing document to a particular person."
- I question whether it is responsible for wikipedia to provide this information- it reads like instructions on how to poison someone with polonium. This information could be found by someone with some background knowledge doing a thorough search, but I don't think it should be listed in wikipedia. What use does recording/displaying this information have, other than to someone interested in poisoning people?
--Dr V Jones —Preceding unsigned comment added by 84.110.168.43 (talk) 23:54, 28 August 2008 (UTC)
- I think mentioning that polonium is used in anti-static brushes and such is fine, but the way it is currently written is excessive. It does read like a how-to obtain polonium for poisoning, which goes against Wikipedia policies (WP:NOTHOWTO). --Itub (talk) 09:27, 1 September 2008 (UTC)
Production, purification and other chemical, physical and biological characteristic
Polonium
Harvey V.Moyer Ohio State University;
Lloyd B.Gnagey Mound Laboratory, Monsanto Chemical Company;
Adrian J.Rogers Mound Laboratory, Monsanto Chemical Company;
July 1956
This report was prepared as an account of work sponsored by an agency of the United States Government.
http://www.osti.gov/bridge/product.biblio.jsp?query_id=0&page=0&osti_id=4367751
26.241 KB, 401 pag. —Preceding unsigned comment added by 82.52.35.137 (talk) 20:10, 14 September 2008 (UTC)
crystal structure
the text says 'cubic' but the picture looks rhombohedral. compare with oxygen, bismuth. 99.231.208.23 (talk) 13:39, 1 May 2008 (UTC) It is definitely simple cubic. The only element with this crystal structure, oddly. The graphic is wrong. —Preceding unsigned comment added by 70.108.20.173 (talk) 03:47, 18 July 2009 (UTC)
- Could you explain why the File:Alpha po lattice.jpg (which is the picture in the article) looks rhombohedral? Materialscientist (talk) 04:05, 18 July 2009 (UTC)
Maybe it's just an optical illusion, but File:Alpha po lattice.jpg does appear to be taller than it is wide or deep – i.e. tetragonal. Ben (talk) 12:21, 18 July 2009 (UTC)
- True (vertical elongation). Squashed the image, but the balls now look squashed too. Materialscientist (talk) 23:14, 18 July 2009 (UTC)
Category Science and technology in Poland
Is the word IN here implying that the science is done within the boarders? If yes the category is wrong.--Stone (talk) 19:10, 19 September 2009 (UTC)
Polonium Restaurant
The Polonium Restaurant (a Polish restaurant) I think has no place in the article, therfore Ideleted it.--Stone (talk) 18:38, 12 January 2009 (UTC)
I added it because it was newsworthy (international news), not as advertising. I have no connection with the restaurant and have never eaten there. AdamFunk (talk) 20:11, 24 November 2009 (UTC)
Tobacco smoke
On 3 January, 2008, anonymous editor 142.179.116.145 changed the sentence "Polonium has been found in tobacco smoke from tobacco leaves grown with phosphate fertilizers." to "Polonium has been found in tobacco smoke from tobacco leaves grown with phosphate fertilizers, though similar amounts occur in everything from cherries to human tissue." [7] No additional sources were cited, and I haven't found any confirmation of this elsewhere. I find the "human tissues" claim hard to believe without a specific citation. The "cherries" claim is irrelevant because people don't inhale cherries into their lungs. Finally, the phrase "everything from cherries to human tissue" is meaningless and inherently POV. Cherries and human tissue are completely disparate and it isn't possible to talk about the range of "everything" between them. Without a source to tell us what, exactly, is in this supposed range, I don't see a way that the claim can be rephrased besides "although cherries and human tissue contain comparable amounts", which seems to give undue weight to the significance of cherries and human tissue as standards for comparison. I am therefore removing the claim. mistercow (talk) 16:16, 17 March 2008 (UTC)
I looked at the talk page because I saw that the source of polonium was fertilizers, and thought to myself: "Doesn't that mean it's also in food?" Seeing as polonium is also toxic when ingested and most of us eat more than we smoke, the cherries reference is definitely relevant, and the source is a scientific journal so it's not fluff. As for 'human tissue' being given undue weight, WTF? Isn't that what we're most concerned about? (There's also antimatter and gamma-rays in your body and all around you, BTW, as far as that believability thing goes.) There was no reason to take the line out other than your personal POV, so I'm putting a modified form back in. —Preceding unsigned comment added by 82.136.242.43 (talk) 02:26, 17 February 2010 (UTC)
Polonium Volatility
While there exist polonium-containing compounds that are volatile at low temperatures,<ref>"Mabuchi, H. J. Inorg. Nucl. Chem. 1963, 25, 657-660".</ref> polonium metal itself is not, to my knowledge, volatile (do you have a reference?). Since there are many volatile metal complexes (e.g. Nickel tetracarbonyl is one of many), I would be hesitant to consider this unique enough to merit mention in the introductory paragraph.
131.215.55.240 (talk) 21:44, 16 March 2010 (UTC) AG, Graduate Student, Department of Chemistry, Caltech.
Actually ... it´s difficult. Polonium has indeed a high boiling point which leads to the assumption, it should not be a volatile element. But it is radioactive; long-lived polonium isotopes decay by alpha emission causing an effect known as sputtering. Due to momentum conservation, decaying recoil atoms (Pb) have energies of about 100 keV, an energy high enough to break several thousand of bonds in the Po crystal lattice. On the surface of such a crystal heavy "eruptions" would cause Po atoms to be released (in atomic or cluster form) into the surrounding. This effect was first observed some 90 years ago by R.W. Lawson. There are some articles claiming highly active polonium samples do spread over the laboratory if not shielded properly. Po may even creep against gas counter-flows as Po-clusters are transported due to a "kick" of a decaying Po atom within this cluster.
The volatility would thus depend on the half-life of the alpha decaying Po isotope. —Preceding unsigned comment added by 84.75.189.10 (talk) 17:19, 20 March 2010 (UTC)
a similar effect is observed for the Pu-238 isotope. Gd-148 and Cm-242/244 should exhibit similar behaviour. —Preceding unsigned comment added by 84.75.189.10 (talk) 23:07, 27 October 2010 (UTC)
Metal or Metalloid
I've heard conflicting sources from different areas on whether polonium is a metal or a metalloid. I've actually heard from some places that the prevailing scientific belief now is that it is a metal, recently (although this doesn't matter much) my science teacher said the same thing. So what is it? A metal or a metalloid? —Preceding unsigned comment added by 67.86.150.191 (talk) 15:09, 6 September 2010 (UTC)
- It is more a metal than a metalloid. The next element astatine is more a non metal than a metalkoid so this would make the period metalloid free. This has to be disused for some time and than it is ripe to be incorporated into wikipedia.--Stone (talk) 20:55, 2 November 2010 (UTC)
go sc/periodic/Po At Metalloids.pdf says that polonium is a metal. —Preceding unsigned comment added by 71.217.85.118 (talk) 21:07, 22 December 2010 (UTC)
Contradiction over polonium quantity?
In the section “Po-210 concentration in the body of Litvinenko” it says “The symptoms seen in Litvinenko appeared consistent with an administered activity of approximately 2 GBq (50 mCi) which corresponds to about 10 micrograms of 210Po”. While in the section “Sources and production of polonium” it says “A freelance killer would not be able to obtain polonium legally from commercially available products in the amounts used for Litvinenko poisoning, because more than microscopic amounts of polonium can only be produced in state-controlled nuclear reactors”
This sounds like a contradiction to me. I have not checked the density of Polonium but I suspect that 10 micrograms would be a microscopic amount and therefore there is an implied contradiction in the article.2.219.126.222 (talk) 14:13, 29 August 2011 (UTC)
Residential Radon and Po
Can the article indicate that radon emitted from granite lurks in the basements of houses in granite areas. It is dangerous because Po, as the breakdown product of radon, attaches to dust particles and is inhaled and lurks in the lungs? This is mentioned in the Po Talk page but not in the article. === Vernon White (talk) 22:02, 25 December 2006 (UTC)
- Actually, the "Chronic effects" section already states that The general population is exposed to small amounts of polonium as a radon daughter in indoor air; the isotopes 214Po and 218Po are thought to cause the majority[1] of the estimated 15,000-22,000 lung cancer deaths in the US every year that have been attributed to indoor radon.[2] Feel free to add a little more (sourced) detail if you think it is called for. --mglg(talk) 19:24, 3 January 2007 (UTC)
- So if 214Po and 218Po are the natural isotopes of Polonium shouldn't they be in the info box with their natural abundance rather than the synthetic isotopes. --Henrygb 10:50, 9 March 2007 (UTC)
I think it's OK as it is. Po-214 and Po-218 are the short-lived decay products of Rn-222, which decay into longer-lived Po-210. So the three polonium isotopes would contribute most of the internal radiation dose of someone breathing air in a high-radon environment. Being solids, these polonium isotopes stay in the body until they decay, unlike radon itself, most of which would be exhaled before it decayed. However, for someone remaining in a high radon environment for several days or more, equilibrium conditions would be reached (since each breath's exhaled radon is replaced by fresh radon in the next breath) so radon and each of its radioactive daughters would contribute approximately equally to the total exposure.CharlesHBennett (talk) 15:51, 26 January 2012 (UTC)
polonium in the biosphere
I replaced the sentence about "natural radioactive fallout" by an explanation of how polonium is generated in the atmosphere from radon gas, then falls to the earth and gets incorporated into the biosphere. The process is somewhat analogous to fallout in the usual sense of the word (radioactive contamination from atmospheric nuclear explosions falling or raining down to the earth), but the word fallout is likely to be confusing because it is almost always used in the context of anthropogenic contamination, so a casual reader might think that polonium is a significant component of fallout from weapons tests, which it isn't, not being a fission product. CharlesHBennett (talk) 16:14, 26 January 2012 (UTC)
Chemically toxic?
How could anybody possibly know (or care) whether polonium is chemically toxic "with poisoning effects analogous with tellurium", given that the LD50 of tellurium is 20 mg/kg, meaning that a fatal dose for an adult human would be more than a gram, whereas nanogram quantities of polonium will kill you by its radiation? Unless somebody provides a source, I suggest we drop the statement about chemical toxicity. --mglg(talk) 19:27, 12 December 2006 (UTC)
- It is still a matter of speed, radiation can/could take way longer than the chemical, so I still believe it is important. --Dirk Beetstra T C 19:30, 12 December 2006 (UTC)
- Certainly needs a good reference, since it seems absurd on its face. I would expect that a dose that is sufficient to be damaging chemically would kill you by radiation extremely rapidly. In general, an acute radiation dose of a few Sv causes bleeding from the gut within minutes[8]. A one-gram dose (approximately the LD50 of tellurium metal) of 210Po would cause 40 million times more radiation exposure than that. --mglg(talk) 21:41, 12 December 2006 (UTC)
- I think that you are right in the case of polonium, but still chemical poisoning is also one of the properties of the metal (but then, most of the metals in that corner of the periodic table are toxic, if I am correct. I don't know enough about toxicology to know if one could get administered 1.6 grams of polonium and die from that dose (calculation does not hold perfectly, it is an LD50, and not tested on humans), instead of the radiation. Maybe other isotopes than 210? But in all cases, a reference would be nice.
- Oh, I am thinking now .. how do they know the LD50 is 20 mg/kg (they measured it, right?). So one must be able to survive significant amounts without being killed by radiation (or at least a rat or a rabbit must have survived many milligrams of it). Time to call in an expert. --Dirk Beetstra T C 22:02, 12 December 2006 (UTC)
- The LD50 of 20 mg/kg was for tellurium, not Polonium. --mglg(talk) 22:32, 12 December 2006 (UTC)
- OK, since no convincing argument to the contrary has been voiced, I am dropping the statement about chemical toxicity. --mglg(talk) 19:24, 3 January 2007 (UTC)
- The LD50 of 20 mg/kg was for tellurium, not Polonium. --mglg(talk) 22:32, 12 December 2006 (UTC)
- Certainly needs a good reference, since it seems absurd on its face. I would expect that a dose that is sufficient to be damaging chemically would kill you by radiation extremely rapidly. In general, an acute radiation dose of a few Sv causes bleeding from the gut within minutes[8]. A one-gram dose (approximately the LD50 of tellurium metal) of 210Po would cause 40 million times more radiation exposure than that. --mglg(talk) 21:41, 12 December 2006 (UTC)
- While the relevance of Polonium being chemically toxic might be up for debate, there shouldn't be any link to the Litvinenko poisoning since that was a death of radiation poisoning only. — Preceding unsigned comment added by 128.61.156.90 (talk) 14:51, 17 May 2012 (UTC)
Edit request on 4 July 2012
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"clothes" is misspelled in the famous poisoning cases
207.139.237.114 (talk) 12:15, 4 July 2012 (UTC)
- Fixed, thanks. Materialscientist (talk) 12:21, 4 July 2012 (UTC)
Possible stable isotopes
The Isotope OE83Bi209 is given as the last (Stable) atomic isotope. However it only has 43 extra neutrons whereas EE82Pb208 is stable with 44 extra neutrons. This brings up the question of why a naturally occurring isotope of either EE84Po210 (42 extra neutrons) or EE84Po212 (44 extra neutrons) shouldn't be be more stable than the OE83Bi209.Has anybody examined old samples of EE84Po210 to see if there is any residual indicationa of a stable Po210 isotope. WFPM68.89.1.0 (talk) 12:13, 9 April 2008 (UTC)
- I'm not sure I understand your question. Po-210 and Po-212 don't have isotopes, they are isotopes of polonium. Do you mean whether any of them might have nearly-stable nuclear isomers? I suppose that's possible in principle, but it would seem highly unlikely that they hadn't been discovered yet. In any case, I don't think you can infer anything about potential stability of polonium isotopes by simple comparisons to proton/neutron counts in isotopes of neighboring elements. Hqb (talk) 15:05, 9 April 2008 (UTC)
I am building real physical models of atomic nuclei and note that whereas EE nuclei can be built to appear dynamically balanced and thus appearing to be stable, the EOs and both OOs and OEs cannot. Thus EE82Pb208 appears stable as does 206 and 204. The additional proton of OE83Bi209 makes it appear unstable but is balanced by an additional proton to make EE84Po210. Since natures production process would undoubtedly pruduce some of everything I wonder if our 83Bi209 plus neutron flux process is capable of producing all the possible structures of EE84Po210 that is possible, and that some of these EE type possibilities might be stable.WFPM 65.65.224.94 (talk) 17:03, 9 April 2008 (UTC)See Talk:Nuclear model WFPMWFPM (talk) 03:49, 29 May 2008 (UTC) The interesting thing about 84Polonium is that it was discovered by the Curies who were not looking for stable isotopes of anything, but were looking for the source of the intense radiation in pitchblend (Uranium Oxide ore] using an electroscope. They isolated the most radioactive material and chemically analyzed it and came up with a radioactive isotope of polonium (and of 88Radium) which was their goal. But in the meantime 84Polonium remains an even Z element just beyond 83Bismuth in the periodic table and is the most logical candidate for the occurrence of some stable EE isotopes. And the Curies definitely wouldn't have found them with their process. And so the search for stable EE isotopes of both 84Polonium and 86 Radon remains a desirable goal.WFPMWFPM (talk) 21:02, 6 September 2008 (UTC)
- Bagnall states that although stable Po isotopes have frequently been searched for, George de Hevesy failed to find one, although Hulubei claimed one from X-ray study evidence. Meitner hypothesized a stable isotope around 218Po, but this seems unlikely. Bagnall states that Hulubei's isotope, if it is Po, might simply be a nuclear isomer of an already known Po isotope. Double sharp (talk) 04:46, 22 June 2012 (UTC)
- EE84Po218 would consist of 84 deuterons plus 50 extra neutrons and have a stability trend number of A = 3Z - 34, which is above the dominant stability trend in this area. If we use the stability trend line through EE82Pb208, which is A = 3Z - 38, we get for 84Po a value of A = 3x82 - 38 = 214, so the atomic numbers 210, 212, and 214 sound more reasonable. Also Extra neutron values of A = 3Z - An even number divisible by 4 is preferable which would indicate a preference for either A = 210 or 214.WFPM (talk) 01:36, 29 November 2012 (UTC)
- Most importantly, though, if it's stable it should occur naturally. It would be an outstanding claim to say that Po has a stable isotope that stars nevertheless did not synthesize.--Jasper Deng (talk) 05:01, 22 June 2012 (UTC)
- The situation is that, after the 7 stable isotopes of 80Hg and the 4 stable isotopes of 82Pb, a comparison of the stability trends of the 49In to 54Xe series with the 81Th to 86Rn series does not show a reason why the decline in the stability of the accumulated nucleus should be so abrupt. The Elements of the elements 52Te and 54Xe are noted to be able to continue to create stable EE isotopes with increased extra neutrons up to a maximum of 28 for EE54Xe136, and after that the number of stable of extra neutron stable isotopes falls through +26 for EE56Ba138 down to +23 for OE59Pr141. So from a structural standpoint the possibility of stable EE isotopes of 84Po and even 86Rn is apparent. By analogy, the advent of alpha particle emission instability might be suspected to begin with the accumulation of the next 2 deuterons of elements 87Fr and 88Ra due to the structural instability factors involved. It is reasonable to assume that the accumulation processes of the stars probably produced some of everything. That is why the residue (as well as our other nucleus creating activities),should be examined for particularly probable stable isotope possibilities.WFPM (talk) 18:18, 25 November 2012 (UTC)
end of article
I still find it a rather abrupt ending, ending on a one-sentence paragraph! Double sharp (talk) 15:47, 28 July 2013 (UTC)
polonium chemistry
To use to expand: [9].
Also, does anyone have [10] or [11]? Double sharp (talk) 16:17, 17 August 2013 (UTC)
- From John S. Thayer's Chemistry of heavier main group elements: PoF6 has weakened bonding because of relativistic effects. Po(VI) could be more stable in polyfluoride and polyoxide anions. Po(IV) is similar to Te(IV) and forms diketonate complexes like Zr(IV), Hf(IV) and Rf(IV). It is stable in aqueous solution over a wide range of pH. Po(II) is readily oxidized to Po(IV), but also common, and Po2+ coprecipitates with many M2+ salts. Po(III) was claimed but never actually confirmed. Po(V) occurs in PoO+
2, but is unstable; electron transfer happened immediately after, forming PoO2. Gaseous polonium is in diatomic molecules. PoH2 could be Po(−II) instead of Po(II). The other Po(−II) compounds are all polonides. Double sharp (talk) 15:12, 18 August 2013 (UTC)
Arafat
Several attempts have been made by IP editors to add the breaking news today about Arafat and Polonium. Most have been reverted for lack of a reliable source. A Reuters news report can be found here (and repeated at Huffington Post here), but I am not advocating for the inclusion of this material at this time. I believe that NOTNEWS should apply until this has time to be further developed. Moreover, if that source is to be used, it must be carefully used not to say more than what it actually says, which is that Arafat's wife says that she has received such a report from the Swiss forensics team, and that an expert hired by Al Jazerra has examined the Swiss results and confirmed polonium poisoning. In short, it is a reliable source for what certain people say, not for the truth of what they say. Since this is breaking news and is certain to be more fully fleshed out in the future, that's a particularly important distinction for encyclopedic purposes and is, frankly, one of the reasons why NOTNEWS should probably prevent it from being included right away. Regards, TransporterMan (TALK) 18:14, 6 November 2013 (UTC)
If the report itself is sourced, is that adequate? The report is available here: http://www.aljazeera.com/investigations/killing-arafat/swiss-forensic-report-arafat-death-201311671255163780.html — Preceding unsigned comment added by 98.111.238.122 (talk) 02:28, 7 November 2013 (UTC) This report (dated 5 Nov 2013 is also available from http://s3.documentcloud.org/documents/815515/expert-forensics-report-concerning-the-late.pdf
- The Arafat content concludes he was not poisoned. Why is this in the poisoning cases section? Widefox; talk 01:56, 18 January 2014 (UTC)
"polonium is chemically similar to bismuth"
In the lead. I query this statement on 2 grounds. 1) it does not make any chemical sense. 2) it is not supported by any mention of Bi in the text body. Petergans (talk) 21:44, 3 May 2013 (UTC)
- It may be true to some extent, as Po was reported by the Curies to be similar to Bi in their first experiments. Double sharp (talk) 10:30, 21 September 2014 (UTC)
Reference
Source #1 doesn't works. DOI link returns: Error 404. Can anyone fix it? I've tried even with Google scholar, but nothing found.--C3r4 ((ask me)) 20:33, 24 March 2015 (UTC)
- Good catch. It's indeed broken, which is pretty bad since it seems to be cited in a bunch of other articles as well. With a bit of googling, I found the actual reference:
- Thayer, John S. (2010). "Relativistic Effects and the Chemistry of the Heavier Main Group Elements": 63–97. doi:10.1007/978-1-4020-9975-5_2.
{{cite journal}}
: Cite journal requires|journal=
(help) (adjust page numbers as appropriate) - The DOI was missing its hyphens (10.1007/9781402099755_2 vs 10.1007/978-1-4020-9975-5_2) and the title was off as well, so you couldn't just search for the title either. Fixing it now. Kolbasz (talk) 20:48, 24 March 2015 (UTC)
- I've fixed 10 or so of them. If someone wants to fix the remaining 75 or so, have at it... Kolbasz (talk) 21:12, 24 March 2015 (UTC)
- @Kolbasz, good job. That was fast. --C3r4 ((ask me)) 11:28, 25 March 2015 (UTC)
Phosphate fertilizer
"Some of the world's biggest tobacco firms researched ways to remove the substance – to no avail – over a 40-year period ... Radioactive polonium-210 contained in phosphate fertilizers is absorbed by the roots of plants (such as tobacco) and stored in its tissues"
So, umm.... If you really wanted to remove it, wouldn't you just use a different fertilizer? —Preceding unsigned comment added by 71.167.65.84 (talk) 00:44, 5 May 2009 (UTC)
Great section(tobacco) - to whoever wrote it. Do you have anymore info on the deaths from tobacco - what besides polonium is doing the dirty deed, if anyone knows? I suspect/ed and actually heard someone say ( but I forgot where unfortunately ) that polonium in tobacco gives you lung cancer and polonium in your meat and milk is just about as bad for your guts,etc. Maybe this is why people who can afford to do it are buying "organic food". One of the legal requirements of the federal defintion is that no artificial fertilizer can be used. I wonder if this is broadly know in the "can afford it crowd" or maybe they are reacting to a hip fad that just might save their hides - if they can avoid the hormones in the water. By the way - I believe the polonium can be extracted but it would cost too much for us "can't affords" to buy food. Without the polonium laced fertilizer the agricultural productivity would plummet - need more farmers, more land, more work, more cost, .... 159.105.80.141 (talk) 14:33, 5 February 2010 (UTC)
Both above are right - they tried to remove it at the factory ( nuts it wouldn't give up its grip once it is grown in the stuff.) And they could use other fertilizer but the polonium rich stuff is dirt cheap and cutting their profits just isn't viable for the rich and how could we afford our credit cards if we had to double our food budget and finally no politician ( Obama, Bush,Clinton, Bush, Carter, Ford, Nixon,...... wants to hear a word about this - along with our hipsters from VT like Bernie,Pat and what's his name).159.105.80.141 (talk) 14:38, 5 February 2010 (UTC)
- Polonium is also present in the soil as well as other radioactive isotopes such as 238U, 234U, ans 226Ra so it is probably not a just a fertilizer issue. It would be interesting to know how many sieverts per year we are talking about through ingestion and how it compares with radiation from other sources (tobacco smoke, background, air travel) but I haven't been able to find a comparison anywhere. 72.15.34.235 (talk)
Polonium is present in nature - but in tiny amounts(otherwise we would all be dead). Fertilizer must contribute most of the polonium exactly where you don't want it - at the plants roots ( not just tobacco). To fix this would take time - question( how long does polonium take to die out of the soil? Till then we are screwed since this stuff is used on almost all crops. Even raising food "organically" wont make much difference until the soil is "organic".
73.149.116.253 (talk) 15:23, 21 June 2015 (UTC)
Polonium glows
Article states: "A few curies (1 curie equals 37 gigabecquerels, 1 Ci = 37 GBq) of 210Po emit a blue glow which is caused by excitation of surrounding air." Since a curie is a measure of decays, not mass, this doesn't really say anything about Polonium. One could just as easily say "A few curies of any alpha-emitter emit a blue glow". It's not saying anything specific to Polonium, so I don't think it should be there. 76.254.25.91 (talk) 16:50, 29 August 2012 (UTC) --76.254.25.91 (talk) 16:50, 29 August 2012 (UTC)
GA Review
GA toolbox |
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Reviewing |
- This review is transcluded from Talk:Polonium/GA1. The edit link for this section can be used to add comments to the review.
Reviewer: Gilderien (talk · contribs) 21:49, 7 April 2013 (UTC)
I shall take a look at this over the next few days, though shall be unavailable for the period 10-13th of April.--Gilderien Chat|List of good deeds 21:49, 7 April 2013 (UTC)
First thoughts are:
- Some of the article needs references - for example, the whole detection section, the Manhatttan Project use paragraph, etc.
- Ref added for the latter. Double sharp (talk) 15:54, 8 April 2013 (UTC)
- I think I finished adding refs. There may be a few more. Double sharp (talk) 14:10, 27 April 2013 (UTC)
- Ref added for the latter. Double sharp (talk) 15:54, 8 April 2013 (UTC)
- "Death cases" - what does this mean? Deaths? Potential deaths? Please clarify.
- Could you tell me where it is? Double sharp (talk) 14:10, 27 April 2013 (UTC)
- The idea about Marie Curie naming it after her homeland for political means is controversial, please source.
Done (though apparently not by me). Double sharp (talk) 15:41, 8 April 2013 (UTC)
- "Results are expected April 2013". Wikipedia is not a crystal ball - either they have arrived or not, and should be added at the appropriate moment. I have seen numerous articles which say "so-and-so is expected by the fall of 2005" still - these sort of sentences may be potentially useful now but will become dated very quickly.
Done Changed to "results have not yet been released". Also added ref. Double sharp (talk) 15:45, 8 April 2013 (UTC)
- Infobox - no references for this data, presumably there should be.
- WP:Elements couldn't figure out an elegant way of sourcing their infoboxes without bringing too much clutter. As it stands, the button "r" at the bottom leads to a collection of datasets (actual sources), which in turn are all referenced and watched against unwarranted changes by new editors. Only data that are not present in those standard datasets are separately referenced in the infoboxes. Materialscientist (talk) 23:21, 7 April 2013 (UTC)
Apart from these the article is "Good" and should be fairly easy to improve to the required standard.--Gilderien Chat|List of good deeds 23:01, 7 April 2013 (UTC) GA review – see WP:WIAGA for criteria
- Is it reasonably well written?
- A. Prose quality: Yes. -
- B. MoS compliance:
- A. Prose quality: Yes. -
- Is it factually accurate and verifiable?
- A. References to sources: Yes, almost all sources online -
- B. Citation of reliable sources where necessary:
- C. No original research:
- A. References to sources: Yes, almost all sources online -
- Is it broad in its coverage?
- A. Major aspects:
- B. Focused:
- A. Major aspects:
- Is it neutral?
- Fair representation without bias:
- Fair representation without bias:
- Is it stable?
- No edit wars, etc:
- No edit wars, etc:
- Does it contain images to illustrate the topic?
- A. Images are copyright tagged, and non-free images have fair use rationales:ne well-justified fair use image, all others acceptable -
- B. Images are provided where possible and appropriate, with suitable captions:
- A. Images are copyright tagged, and non-free images have fair use rationales:ne well-justified fair use image, all others acceptable -
- Overall:
- Pass or Fail:
- Pass or Fail:
--Gilderien Chat|List of good deeds 10:06, 28 April 2013 (UTC)
I read recently that when polonium was first discovered people would go to parties( scientific events were popular at the time) and get to hold a glowing chunk of polonium. It was quite the rage. Then scientist who handled the stuff started dying and the rage cooled off.
73.149.116.253 (talk) 15:28, 21 June 2015 (UTC)
Tobacco is not an application
In the Applications section, the risk of inhaling Polonium through smoke is highlighted. However, this is not an intentional application. Should this text be moved to the health risks section? 83.84.34.28 (talk) 14:22, 23 June 2015 (UTC)
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Note (2005)
Article changed over to new Wikipedia:WikiProject Elements format by maveric149. Elementbox converted 12:28, 10 July 2005 by Femto (previous revision was that of 06:33, 9 July 2005).
Information Sources
Some of the text in this entry was rewritten from Los Alamos National Laboratory - Polonium. Additional text was taken directly from the Elements database 20001107 (via dict.org), Webster's Revised Unabridged Dictionary (1913) (via dict.org) and WordNet (r) 1.7 (via dict.org). Data for the table was obtained from the sources listed on the main page and Wikipedia:WikiProject Elements but was reformatted and converted into SI units.
Ok, and what about protactinium it eletroafinity is most higher than any lanthanide or actinide, and it decays to actinium both with half-life of around 30.000 years, they are very very dangerous, and who says it's a poison?, none, because it's scarce!
- old. -DePiep (talk) 14:29, 24 February 2017 (UTC)
How to make this article not suck
Polonium and technetium are the only two radioactive elements on the periodic table that Greenwood and Earnshaw tries to treat as normal, upright, stable citizens: they cover Po with Se and Te, and Tc with Mn and Re. (Admittedly they also try for Pm and At–Ac, but without much success: there just isn't enough known to say anything.) Technetium is already an FA, so I will instead write here about how to make my beloved polonium a wonderful article!
- History
- We should really talk more about the Curies. Yes, I know everyone knows the story, but that's not an excuse to avoid illustrating it beautifully.
- It is worth mentioning that polonium was the first element that was first identified and found solely by its radioactivity (though it was isolated by Marckwald, who assumed correctly that it would behave like tellurium). (Radium came later and was partially identified by its chemical similarity with barium.)
- BTW, the Curie's statement that polonium shows similarities with bismuth must be explained. I suspect this is more a reflection on metallic character. Like Tl, Pb, and Bi, Po is a metallic conductor with a medium-high density and low melting and boiling points.
- Detection
- This is more about how to find α- and γ-emitters in general than about 210Po. I would move this somewhere else and just note that polonium, like other α- and γ-emitters, can be detected in these ways in another section.
- Occurrence and production
- The focus of production should be 210Po, because, for better or worse, this is the polonium isotope that has told us the most about the personality of the element. This is because it is easy to produce by the reaction 209Bi(n,γ). (You have to use very high-purity bismuth, because 210Po has a short half-life and we don't want to waste time tediously separating it out from all manner of side products, many of which are metals that can form polonides.) And we should mention that (and explain why) this makes it difficult to investigate Po(VI) compounds...
- Application
- Tobacco smoke is not an application of polonium. It is a danger.
More later.
P.S. You can legally buy 0.1 μCi 210Po sources! They are exempt from the regulations! Double sharp (talk) 05:57, 16 July 2016 (UTC)
- P.P.S. The end of this article is kind of a "laundry list" that is uncertain of what its point is trying to be. What is the main thrust of the last section, which is currently just a list of things that happen to have polonium in them, deliberately or otherwise? (And should not the deliberate cases count as applications?) Double sharp (talk) 05:58, 16 July 2016 (UTC)
Te is the first in the group to show cationic properties that are firmly dominant by Po (and this is why it should really be considered a metal). A metal and a chalcogen! Perhaps we should also explain why this happens, why Po wants to lose electrons more readily than it wants to gain electrons when it only needs two more. (Yes, this is all basic stuff, but not everyone is going to read all the related articles.) In general, we should compare all the trends down the chalcogens from sulfur downwards. Sulfur catenates readily, selenium and tellurium do it more reluctantly, and polonium doesn't do it at all. (No polypolonides are known, though I have to wonder if this is something real about polonium's personality, or because no one's actually tried to make any.) Its hydride is really not very thermally stable (although it's cool to note that like water, it's a liquid, because the van der Waals forces are now strong enough.)
More details on structures of Po compounds please! (Together with references to the similar chalcogen compounds when possible, e.g. SeBr2−
6 and TeBr−
6 compared with PoI2−
6, all octahedral.)
It is also really funny that PoCl2 and PoBr2 are the most well-known chalcogen dihalides.
Greenwood as well as Bagnall call PoSO3 a sulfoxide rather than a sulfate. This is again something that needs explanation. Double sharp (talk) 06:07, 16 July 2016 (UTC)
- I wonder if this has anything to do with how metalloid "salts" have a tendency not to live up to their august reputation, like antimony sulfate? That would seem to suddenly make the case for calling Po a metalloid much sounder! Double sharp (talk) 16:51, 4 April 2017 (UTC)
Organopolonium compounds are a thing, although they are quite prone to charring and decomposition via radiolysis. Source. Po is metabolised in much the same way as Se and Te by bacteria, producing Me2Po. Looking at its vertical neighbours, it would be tough to decide if the stink would kill you first, or the radiation. Double sharp (talk) 06:13, 16 July 2016 (UTC)
Element Category
What is the element category for Polonium? The article says "post-transition metal, but this status is disputed". I always see polonium colored in the post-transition metal category on Wikipedia, but in many periodic tables, polonium is colored as part of the metalloids.
Why is polonium disputed? --RedLightningStrike (talk) 13:28, 9 December 2018 (UTC)
- @RedLightningStrike: Metalloid#Polonium gives some explanation. In any case, the boundaries of these categories are quite disputable; they are just a more or less artificial way of dividing up a real variation. Double sharp (talk) 05:35, 10 December 2018 (UTC)
Chemistry review
10.1524/ract.1983.32.13.153 Double sharp (talk) 16:24, 19 August 2019 (UTC)
- (Es through Db are 10.1524/ract.1983.32.13.7; Tc and Rn are in that issue too, see https://www.degruyter.com/view/j/ract.1983.32.issue-1-3/issue-files/ract.1983.32.issue-1-3.xml.) Double sharp (talk) 16:25, 19 August 2019 (UTC)
"Radio-tellurium" listed at Redirects for discussion
![](http://up.wiki.x.io/wikipedia/en/thumb/2/28/Information.svg/30px-Information.svg.png)
An editor has asked for a discussion to address the redirect Radio-tellurium. Please participate in the redirect discussion if you wish to do so. ComplexRational (talk) 15:00, 11 November 2019 (UTC)
Atomic radius
In February 202.142.183.148 added to article this discussion of some peculiarities of Polonium's atomic radius. Today it was partially removed by 116.71.4.85. I decided to remove the remainder of the text, as I could not find a source which confirms that Polonium is breaking radius trend in its period. Additionally I can't find the exact radiuses cited for lead and bismuth (154pm) and polonium (167pm) on elements' pages nor on Atomic radii of the elements (data page). On the other hand, this text really looks as if someone knew what they were writing, so maybe it could be verified and salvaged... – attomir (talk | contribs) 22:27, 9 June 2020 (UTC)
- @Attomir: Pb 6p is not half-filled, as the text claims. Actually the ordering here has a p-orbital split, so Tl and Pb fill one p1/2 orbital first, then electrons go in p3/2 for Bi through Rn. 6s16p3 for Pb as claimed is kind of unlikely, inert pair effect stabilises the 6s2 lone pair (Pb prefers the +2 state to the +4 state, even in organometallics like PbEt4 6s is mostly nonbonding MO). The covalent radius of Po does not look terribly trend-breaking (Tl 144 pm, Pb 144 pm, Bi 151 pm, Po 145 pm, At 147 pm, Rn 142 pm). Double sharp (talk) 04:39, 10 June 2020 (UTC)