This is interesting stuff. For one thing, it does a good job of showing the extreme lengths that you must go to to obtain even tiny amounts of plutonium.
There’s a story Richard Feynman told about the spare plutonium core they had at Los Alamos. It sat in a room by itself, unguarded because nobody who knew anything about it would dream of trying to steal it. Mostly, it was for “show and tell” to VIPs – you could walk over and touch it and it was slightly warm to the touch. Enough plutonium to wipe out a city, if it was merely compressed enough around an initiator of Beryllium-9 and Polonium-210.[wik] Feynman said that the door-stop to the room was appropriate: it was a 3″ hemisphere of yellow metal heavier than lead: solid gold. Nobody would steal the gold, either because it was worthless compared to the plutonium. Feyman was a great story-teller and I suspect the tale is embellished, though the Manhattan Project did requisition huge amounts of precious metals including tons of metallic silver to use for something or other to do with separation of uranium isotopes using the early “calutron” electro-magnetic separators that were invented before gas centrifuging came along. (Little birds say that nowadays all the cool kids sort their fissionable molecules using lasers) Anyhow, it is not outside the realm of possibility that some of the Los Alamos eggheads would do something like that, thinking it funny.
It’s kind of sad to see the folks in the video keep emphasizing how great it would be if the plutonium they are making finds its way onto a spacecraft for NASA. Instead of, you know, into the core pit of a city-killer, which is what most of it is destined for. Notice the size of their production line: you don’t need that kind of production line if you’re just making the occasional battery for a satellite.
And: fuck those assholes for trying to pretend that Oak Ridge National Labs is a bunch of scientists that love spacecraft and NASA. Those people know exactly what they are making, and what it means.
I read somewhere that a tiny particle of plutonium in a lung is a death sentence unless you catch the cancer soon enough. They probably hadn’t really figured that stuff out during the Manhattan Project days. There was a lot that was not understood. Feynman also told some stories about doing safety-checks on the plant at Hanford – which, apparently, was not anywhere near as safe as it needed to be. Nowadays that would all be considered very primitive stuff.
During the heyday of the nuclear arms race, the US devoted something like 3% of its economic output to nuclear weapons. Huge programs were put in place for the nukes, and buried under other reasoning. For example the Tennessee Valley Authority and all its massive hydro-electric dams: that was to power Y-12 at Oak Ridge, Tennessee. When I was a teenager, still impressed by nuclear weapons and their awesome power, I did not realize that they represented a decision on the part of the government to produce tools of death and to spend vast resources on something that – in theory – they never wanted to use. Exactly the opposite of what most people think government is supposed to do.
That is one of the calutrons at Y-12. These were electromagnetic separators that worked by taking uranium and spinning it using current like a particle accelerator does. By carefully tuning the speed at which the isotopes spun, the 235- isotope could be made to go through one slit into a collector, or another. That’s one calutron from a bank of, I believe, 32. There was another bank that was tuned differently for other stuff.
American Scientist has some stuff about the government silver that was used in the calutrons: [as] It turns out I was slightly wrong about how it was used: they used 6,000 tons of silver so that it would not interfere with the necessary war-material supply of copper. It was believed at the time that the enemy might figure “something was up” if thousands of tons of the copper supply were diverted, but the silver supply was already diverted and secured and the public had no idea how much was where.
Construction of Y-12 was an enormous undertaking, requiring 67 million hours of labor by a workforce that peaked at about 20,000. The complex included more than 200 support buildings and required some 5,000 operating and maintenance personnel.
*Cough* new deal.
When I worked at Trusted Information Systems in 1992, one of my co-workers, Keith K., mentioned that he had worked at Oak Ridge. I immediately asked him what he could tell me about his experiences there and he thought for a while and then said, “basically – nothing.” Then “oh, wait! I got sent home in a paper suit twice. That’s why I am here. I was not allowed to get any more radiation for the rest of my life.” It turned out that if you got a bad dose of radiation they’d give you the various rad-washes and send you home in a disposable suit made of cellulose fiber – basically gray kraft paper. Your clothes wound up in a concrete coffin somewhere. He said that his accident happened when there was “a bucket of something” on a chain-fall with a motor to move it from one room to another, because the bucket was solid lead, and it jammed. So Keith clambered up onto the gantry and pried the jam with a pry-bar, when a supervisor came running into the room and started shrieking at him to get down from there right this minute! He was directly over the open end of the bucket, and could see down into it; it was full of grey stuff, nothing interesting. Uh, yeah. Keith was an older guy; this would have happened in the late 1950s. When they closed Y-12 the new plants are entirely robotic and – well, if you watch the video you can see what they look like.
Aw, that’s just mean. It’s perfectly possible and reasonable to assume the batch in the video is actually earmarked for NASA.* Maybe the military stockpiles are already full. Maybe NASA begged and whined until they were reluctantly slotted into a busy production schedule. Maybe it’s budget review time and the lab wanted to do a little PR project they could actually talk about. “Last month we made spaceship reactor fuel. Because exploration, science, US greatness and all good stuff.” – “Cool! And what did you do the rest of the year?” – “Uh… renovations?”
*All those maybes and hopefullies are also reasonable: Missions are cancelled all the time. So what’s reserved for today’s mission of tomorrow is tomorrow’s unused leftovers from the budget cut of today.
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From what you tell us, Keith’s bucket incident sounds like a classic case of “need to know”-thinking gone too far. You don’t need to know what you’re working on, what you’re working with or which of materials in this process are actually dangerous.
The video is about production of Pu-238 (the Einstein-lookalike says so in the second or third take he’s appearing in), which isn’t fissile.
Sorry for the double quote. Should’ve checked better before posting.
I recently visited a national lab with a tree in its name. While there my tour group encountered some extremely tactical security guards. The most mind-blowing part to me was who names their ammo clips?
…”who names their ammo clips?”
Name them? None that I know of. OTOH I understand that many professional shooters, snipers and certain people in jobs where firearms reliability is vital mark their magazines to identify them so they can be tracked. I’ve known a few of them. If a failure to load occurs they record which magazine was in use. This allows them to examine it closely to determine the issue. Dirt or dust, oil, dents or bent feed lips can cause reliability issues. If the problem can’t be corrected the magazine is pensioned off, used only in non-critical jobs, or discarded.
Little known fact: Japan was developing an atomic bomb in occupied Korea at the end of the war and may have detonated a working atomic bomb a couple of days after the US atomic bomb was dropped on Nagasaki. A lot of evidence, materiel, and documentation was lost to Russian as it occupied what was to become North Korea.
Hitler also had an atomic bomb program, albeit one that was progressing toward a dead end if the intent was manufacturing a workable weapon.
It is easy to forget that E=MC^2 , conversion of mass into energy, was demonstrated much earlier as a result of studying radioactive decay. The understanding that if a single atom could release easily measurable amounts of energy as it decayed implied possible weapons releasing huge amounts of energy simply because Avogadro’s number (~6.022 x 10^23) is bloody huge number. Any significant weight of matter converted to energy would release a huge amount of energy.
Research directed at potential atomic weapons were clearly not something only the US was pursuing. Many physicists knew it was a possibility. Getting there first was the challenge. We didn’t know how far along anyone was.
… it was slightly warm to the touch.
IOW, radioisotopic breakdown. IOW, even if it started as such, it was no longer pure plutonium.
Pure plutonium emits alpha radiation: you can handle it safely, because alpha particles can’t penetrate skin, and are safe unless in-gested/-haled.
But those daughter isotopes emit beta and gamma. You really want something tougher than epidermis between those and your living cells.
No doubt the medical histories of those carefree Los Alamos workers contributed significantly to that belated understanding.
wereatheist@#2:
The video is about production of Pu-238 (the Einstein-lookalike says so in the second or third take he’s appearing in), which isn’t fissile.
Yes, but the production line for various isotopes depends mostly (solely?) on deciding where to scoop them out of the centrifuge or (I do not understand how this is done:) where to tune the laser. It’s mind-boggling to me but that’s how it’s done – an isotope with one more electron than another weighs just that tiny bit more and can be made to position itself in a slightly different place than the other isotopes.
Since I’m on that topic: Hillis and Rhodes separately describe the science of nuclear forensics in their books [references upon request] – because the process of isotopic separation and “breeding” plutonium are not completely ‘clean’ it’s possible to tell what breeder reactor made which batch of plutonium and what run it was from – there are distinctive fingerprints. Ditto the output from a centrifuge cascade. The US used to fly aircraft through test explosion plumes to sample the byproducts, early in the days of developing the techniques. So, it’s kind of cool to know that, though (obviously) the security state does not make a big deal of the capability: it is impossible to produce an “unknown” nuke. Though the Israelis have come close. (I do not buy that the Vela Incident was an “unknown” nuke – I think it was a perfectly well-known nuke and it came from Dimona)
Ok, as both a nuclear physicist who subcontracts to ORNL and someone who worked as a postdoc in the physics division of ORNL worked with HFIR and to a small extent REDC, I feel the need to pipe up and correct some misconceptions that have been shown here. I am no nuclear weapons apologist, the things are abhorrent to use, but you are painting those facilities with an outdated and, I think, misinformed brush. In no particular order:
First of all, it is much easier to extract 239Pu (used in weapons) from the spent fuel of reactors that have been short cycled (to prevent the buildup of too much 240/241Pu.) 239Pu is produced copiously from 238U in reactor fuel capturing a neutron and then undergoing beta decay twice, which converts it to 239Pu by way of 239Np. If you want plutonium for a weapon, *that* is how you get it, using HFIR to produce weapon plutonium is a gross misuse of resources. There are much better things you can use HFIR / REDC for, they don’t have anything close the throughput required for producing 239Pu for weapons
Marcus Ranum @7
That is not even slightly true for this stuff. You don’t use enrichment methods to separate these isotopes separation of these things is accomplished chemically. Absolutely, uranium isotopes are enriched via calutrons, gaseous diffusion, gas centrifuges, or, more modernly, atomic vapor laser ionization separation (AVLIS). However, separating 235U from 238U is much easier than 238Pu from 239Pu, the percent mass difference is more than a factor of 3 higher for the uranium case than it is for the plutonium case. The factor of 3 in percent mass difference makes separation substantially more than a factor of 3 easier.
To make 238Pu you do the following: First they know that essentially all the neptunium in spent nuclear fuel is 237 neptunium (because the various processes occurring in “burning” nuclear are known and processes that produce neptunium in general are rare and well know). So, we can use purely chemical processes to separate it out. First you dissolve the spent fuel pellets in something nasty like fuming nitric acid. Then you precipitate out the neptunium (I do not know the particular reagent to do this but it is like dissolving silver nitrate in water and then adding table salt to make the silver precipitate out as silver chloride which is insoluble.) Once you do this you have basically pure 237Np which you can then subject to another reaction to get it into solution again, which they start with in the video. Once you have that in pellet you put them in the target to put in a nuclear reactor (in their case the High Flux Isotope Reactor (HFIR)) to absorb neutrons becoming 238Np which quickly beta-decays into 238Pu. I should reiterate, those targets are *not* fuel, the fuel is in annular rings around the targets (you see the fuel being removed in a brief clip at 5:20. This design produces the largest possible neutron flux in the center of the ring, improving the production yield.
They built a production line like that for several reasons, none of them to do with the fact that they want to also use it for making plutonium for weapons. First of all, if a human is doing the steps, that means that the human needs to be in contact with these things, and even in glove boxes, you want to minimize that, while radiation and radioactivity are nowhere near as bad as the public perceives them, they certainly are not harmless, especially for given that actinides are pretty damn poisonous on their own before you factor in their radioactivity. Building a *small* production line (I assure you a production line for weapons related material would need to be much larger and much faster) fits in well with ALARA (as low as reasonably achievable) a guiding principle in design of processes and experiments that will cause radiation exposure above background. Second of all, humans can make mistakes, they have made mistakes, even at REDC / HFIR. These mistakes costly on a lot of levels, radiation dose, paperwork, credibility, etc. If it is something you expect to do a lot and you can get a machine to do it, then, if you have verified the machine’s operation, that is the most sensible option.
Yes they do know what they are making and what it means; but, I am pretty sure that you do not. Almost none of the stuff they produce at HFIR/REDC has anything to do with nuclear weapons. The only thing they produce in any quantity that might be used for nuclear weapons is 252Cf which is sometimes used in the initiator as a neutron source from spontaneous fission. To achieve the extremely high neutron fluxes used in HFIR (which was built as a factory for heavy transuranics, not plutonium or even americium which are easily obtained from spent nuclear fuel, but the hard to get things like curium, berkelium, californium, even einsteinium and fermium.) they use uranium fuel that is already basically weapons grade and have a tiny core shaped like a hollow cylinder. They cannot produce hundreds of kilos of anything per year, and they do not have the facilities to do so. Mostly they produce californium and berkelium for research and medicinal use, although I am told that some of the californium production sometimes goes to the NNSA.
I am very curious to know what you mean by this. They closed K-25, Y-12 is still open and working as a maintenance, storage, and possibly production depot operated by the NNSA. Robotic plants to make uranium might very well look like that, but they would be found at Savanah River and other sites, not ORNL. REDC is the companion facility to HFIR, there to produce targets to place into HFIR and to chemically extract the things produced in those targets for research and commercial use.
I would like to repeat, I am not trying to be an apologist for nuclear weapons, either their creation or production. But I can say with certainty that REDC and HFIR have very little to do with them. Some of the 252 they make might be used in them but they do not produce “fuel” for the weapons nor do them make significant amounts of anything for them.
“That is one of the calutrons at Y-12. These were electromagnetic separators that worked by taking uranium and spinning it using current like a particle accelerator does. By carefully tuning the speed at which the isotopes spun, the 235- isotope could be made to go through one slit into a collector, or another. That’s one calutron from a bank of, I believe, 32. There was another bank that was tuned differently for other stuff”
Here you make it sound, as if the whole circle was one particle accelerator. In fact, the horn like things on the bottom left are the separators, basically sector mass spectrometers. They were build in banks (“racetracks”) and could be removed independently to get the uranium out. The oval shape is a result from handling the magnets that are needed to defleckt the ion beam, a closed loop is was more efficient (whatever that means). There were linear Calutrons as well.
Also thanks to James for the detailed description, I thought there was something “off”. (For example, that they pretty surely would not let someone with a camera in a weapon-grade-Pu-facility.) Pu-Thermal sources are quite a far away from weapons grade Pu, as far as I remembered transuranic chemistry and physics.
Apart from that, Periodic videos is well worth a watch!
To lorn
Minor pet peeve of mine. This is technically incorrect. If you said “conversion of matter into another form of energy” instead of “conversion of mass into energy”, then you would have been correct. The error is a fundamental misunderstanding of general relativity and what “mass” and “energy” are. In short, “mass” is a property that all energy has, and barring unusual circumstances, the law of conservation of energy holds, which means that a law of conservation of mass also holds. When you explode an atomic bomb, if you had it in a big enough box that contained the explosion, and the box was on a perfectly accurate scale, the scale would not move – the mass of the system remains the same before and after the nuclear bomb explosion. During a nuclear bomb explosion, some of the energy stored in the atoms is simply converted to another kind of energy, i.e. high energy neutrons, gamma rays, etc., and because the energy remains constant, therefore the mass remains constant too.
For more information, let me suggest the excellent episode on this topic from the excellent PBS Space Time Youtube series.
https://www.youtube.com/watch?v=Xo232kyTsO0
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To James
Thanks very much. Confusing the production of radiodecay battery plutonium vs the production of bomb plutonium pissed me off. Thanks for the correction.
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To Marcus
In particular for Marcus – I want to emphasize that when you use a conventional uranium pile, you’re going from U-238 to Pu-239. In order to get Pu-238, which is what they use for spacecraft radiodecay batteries, you need to do something completely different. The amount of Pu-238 in stuff from a uranium pile is miniscule, and the effort required to separate it via centrifuges would be heroic because of the small amounts and because of the very small mass difference (as compared to U-235 vs U-238). IIRC, all radiodecay battery plutonium is made an entirely separate way. It seems that James knows what he’s talking about, although I’m too ignorant to vouch for the correctness of the details provided by James.
Regarding the bit about a single “particle” of plutonium causing cancer, guaranteed, if you breathe it in. This claim is probably bullshit.
First, the vagueness of “particle” and the usage of ideas like “guaranteed to cause lung cancer” sounds like it came straight from the lying mouths of Ralph Nader, Helen Caldicott, Green Peace, Friends Of The Earth, and the like. The problem is that almost everything that you know about the dangers of radiation exposure on human health is wrong, and it’s wrong because of a 50 year misinformation campaign by the so-called environmentalists. See:
https://www.theguardian.com/commentisfree/2011/apr/05/anti-nuclear-lobby-misled-world
For particular evidence that this particular claim is incredibly wrong, see here:
https://en.wikipedia.org/wiki/Plutonium
I didn’t examine the source, (too lazy chasing down the many lies of the Greens), but it’s claimed that it comes from Bernard Cohen, whom I consider to be a reliable source.
I realized I mentioned that HFIR’s fuel annuli (sp?) are highly enriched without saying why. The reason that matters is that even reprocessing HFIR’s spend fuel will not produce a useful amount of 239Pu, because there is almost no 238U to capture neutrons.
So you can’t even use HFIR to produce stuff for weapons that way, either.
I strongly suspect that the super computers at ORNL have contributed more substantively to nuclear weapons related things than HFIR or REDC.
@James:
First off, let me thank you for schooling me so hard. It’s always great to hear from someone who is much higher up the knowledge-curve than oneself, even though it’s a bit painful sometimes.
My understanding about enrichment and processes is (as you can tell) pretty basic at best, and is a mixture of old Manhattan Project stuff and more modern sources. Even those sources aren’t exactly detailed. For example, I am pretty sure that I got the bit about the production lines being heavily automated from Richard Rhodes’ Twilight of The Bombs but I hope you’ll forgive me for not rummaging out citations. A lot of the obsolete information I carry is from various bits of Feynman, most notably his “Los Alamos From Below” talk, which I highly recommend if only because he was a hell of a story-teller. I also got a bit of information from a friend who worked at Idaho National Lab. It’s all bits and pieces.
I’m not aware of any book or source that goes into this stuff in any kind of detail. If you have a recommendation, I’d be on it like a starving dog.
Another note: there is a wonderful series of fine art photos that were taken at Oak Ridge. I’m not talking about Ed Westcott’s stuff; there was another guy who got in there with an 8×10 and some black and white film. For any of you who are interested in really cool photos of Oak Ridge back in the day, The Altantic had a good collection of Westcott’s work [atl]
Looking around for those, I see that I did, in fact, confuse K-25 with Y-12. I’m insanely envious of the folks who’ve managed to photograph in those facilities and not wind up in a great deal of trouble.
I’m not going to argue point-by-point about your comment because I’m sure I’m wrong about all the things you say I’ve got wrong. All I can say is “thank you.”
@GerrardofTitanServer:
I want to emphasize that when you use a conventional uranium pile, you’re going from U-238 to Pu-239. In order to get Pu-238, which is what they use for spacecraft radiodecay batteries, you need to do something completely different.
Obviously, I did not knowthat. Thank you.
I remember Feynman said “there was not a lot of theory, it was all engineering” and that has stuck in my mind. The theoretical stuff is probably not too complicated for a nuclear physicist; it’s the ins and outs of making robotic remote-controlled hands and stuff like that.
First, the vagueness of “particle” and the usage of ideas like “guaranteed to cause lung cancer” sounds like it came straight from the lying mouths of Ralph Nader, Helen Caldicott, Green Peace, Friends Of The Earth, and the like. The problem is that almost everything that you know about the dangers of radiation exposure on human health is wrong, and it’s wrong because of a 50 year misinformation campaign by the so-called environmentalists.
Interesting! And now that you mention it, it does sound pretty sound-bitey. This is the sort of thing I was going by:
livescience] Come to think of it “getting plutonium inside a cell” does sound sketchy. I believe that what I first heard was that you get it in your lungs and if it doesn’t come out somehow, it just sits there emitting alpha particles and gives you cancers. Sounds legit.
Again, thank you for your comments; I’m going to try to update my knowledge and won’t argue about details about what I’ve gotten wrong.
Perhaps this is why atheists stick to refuting the Kalam Cosmological argument and stay safe within the bounds of the dictionary. ;)
avalus@#9:
(For example, that they pretty surely would not let someone with a camera in a weapon-grade-Pu-facility.)
Interesting that you assume that; and you may be right. I’d been thinking that the mechanical parts of the process had a great deal of overlap; it appears that was one of my bigger mistakes.
Are you guys trying to tell me that this may contain misinformation?
@Marcus Ranum
Unfortunately, the knowledge doesn’t really come from one source, honestly half the stuff you need to come to the same conclusions can be found just looking at the neutron capture and emit gamma-ray cross-sections, neutron capture and fission cross-sections, and half-lives which can be found at: NUDAT. Plus a basic book or two about introductory nuclear physics Krane’s book is pretty good.
In truth though a lot of this stuff is common knowledge in the nuclear physics / chemistry and health physics fields and comes from the synthesis of many things known to people in those fields plus some application of that synthesis to the unclassified bits and bobs.
Knowing something about the various enrichment processes that get the enriched isotopes needed for experiments tells you that whenever possible you let the nuclear physics do the work for you instead of doing the separation yourself. For instance, in the case of 238Pu you can put 237Np into a reactor for a given amount of time with a given neutron flux then extract all the plutonium from the target you know that you will get a mix of 238Pu with a tiny bit of 239Pu whose fraction will be determined by the various cross-sections and times in the flux (again, for these purposes 239Pu is not the objective because producing even a few hundred of grams of it at a time is pretty much useless).
Knowing that in nuclear power reactors that work on fuel that is not highly enriched (be it the natural uranium of a CANDU reactor or the 3-20% LEU of the more standard boiling water reactor designs) late in the “burning” cycle something like 30-40% of the power generated by the reactor can come from fissioning of the built up 239Pu from activation of the 238U will tell you that you can make a lot of 239Pu in a standard power reactor.
Looking at the cross-sections and solving the rate equations lets you know that 241Pu will build up more slowly in the same environment that is making 239Pu so it lets you know that if you run the reactors in shorter cycles you can minimize the production of the “too fissionable” isotopes so that when you use mere chemical extraction to leach all the plutonium from the used fuel the plutonium you will get is 239Pu with a low enough concentration of 241Pu.
Knowing that the reason that Argonne National Laboratory’s Argonne Tandem Linear Accelerator System (ATLAS) was able to afford their CARIBU upgrade (where they use a big 252Cf source to collect the fission fragments resulting from the spontaneous fission in 252Cf to make neutron rich beams for study) was because the NNSA was already paying for a ramp up in 252Cf production at HFIR tells you that the NNSA has a use for 252Cf. Given the purposes of the NNSA and the timing of that with Obama’s big nuclear weapons servicing you can think about what they might need neutron sources for (once again from the spontaneous fission) and you come to the possible uses of neutron tomography of various devices, or in the initiators to make sure their is already a neutron there. The neutron tomography idea is harder since it is difficult to detect the moment of the neutron’s emission and it’s initial direction (unlike in a D-T generator) so the initiator seems likely, though not guaranteed.
On an unrelated note, it is irksome that they allow the bold and italics tags but not the superscript tags.
Though given a choice between html tags and markdown with KaTeX I will take the latter.
I realize I need to say:
Yes radiation causes cancer. Lot of radiation is very likely to kill you, and greatly increase the chance of developing cancer later in life.
However, for low dose and low dose rates, the public’s understanding of the real cancer risk seems to be exaggerated by a thousand or a million times the real risk factor. This is not an accident. This is the result of 50 years of misinformation by people like Helen Caldicott, Ralph Nader, and various Green organizations like Friends Of The Earth, etc.
@GerrardOfTitanServer #16
Absolutely right. One year as a grad student at Dotre Dame I was making a source for the advanced lab I was a TA for and I got the highest dose of anyone at the university that quarter. It was tiny, 22 milliRem (220 micoSievert if you are using mks instead of cgs) I am as unconcerned about that dose to my hand as I am of my chances of being struck by a meteorite. Sure it could cause something / happen, but you should be infinitely more worried about a bajillion other things. For references XKCD’s radiation chart is a really good reference that has stood up to my random verification tests.
For some radioactive materials the radiation risk is so minimal that the stuff will cause more trouble from a heavy metal poisoning point of view than from a radiation point of view. One example is depleted uranium, that stuff is almost pure 238U whose halflife is so long (1/3 the age of the known universe) that it basically poses no threat radiologically speaking, that said it is a fairly potent poison as far as heavy metal poisoning goes… so don’t go eating it. Another example is 232Th (the only thorium isotope found in nature all the others are too short lived) you don’t want to eat that gas lantern mantel not because it will give you a significant radiation dose (the halflife is on the order of the age of the universe) but because it would be a little bit like eating lead… which is not recommended.
Plutonium is nasty, because it is both a potent radiological and chemical risk, but a particle in the lung shouldn’t be too bad. That said if instead of in metallic or oxide form the plutonium is in some highly soluble form, like plutonium nitrate and it is aresolized, then breathing it would be exceedingly bad.
To James
Speaking of which, one of my favorite things in the world about the absolute ridiculousness of modern radiation safety regs is the following. Modern nuclear power plants in the US use cryogenic equipment in order to capture and sequester Krypton gas – a product of nuclear fission, a radioactive gas. This sort of thing adds millions of dollars capital cost to several nuclear facilities. What’s the scale of the risk that warrants spending millions of dollars? An EPA estimate that should they simply vent it directly into the atmosphere, and nuclear power in the US substantially grew from current size, then everyone on Earth will receive an individual dose of 0.4 μSv/year. And there are no worries about accumulation of any kind, bioaccumulation or otherwise, because it’s a freaking noble gas, aka completely unreactive chemically.
Source:
https://atomicinsights.com/opportunity-use-science-establish-radiation-standards/
Words fail me in describing how ridiculous this is.
For reference for other people, the typical dose of a person from natural background radiation is about 3 mSv / year, aka 3000 μSv / year. We’re spending millions of dollars, billions even, to prevent extra radiation dose that is many orders of magnitude smaller than the background radiation that you already receive from natural sources, including cosmic rays, and the radioactive potassium and carbon in your body that naturally occurs. Remember this next time someone tells you that nuclear is too expensive.
James @ 17: Could you go into why a particle of plutonium in the lung shouldn’t be too bad?
The papers I was looking at suggested that particles of Pu-239 under 5um and especially under 0.8um are far more likely to be retained in the lungs for long periods of time.
To Maya
I don’t know. You may find this link interesting.
http://www.phyast.pitt.edu/~blc/book/chapter13.html
(Search for “lung”.)