I’m curious about the use of depleted uranium in weapons, which now is raising concerns about causing leukaemia in troops exposed to it: NATO urged to probe ‘Balkan Sickness’.
My personal reaction to the idea of carrying around uranium bullets, firing uranium shells, etc., is [Homer voice]Uranium … bad![/Homer voice], but apparently military munitions folk think otherwise.
Even if it is “depleted” isn’t there always some radiation associated with uranium?
It’s not just a good idea, it’s a great idea. DU ammunition slices through enemy armor like nothing else can.
DU ammo isn’t dangerously radioactive until it strikes a surface hard enough to cause it to burn - like tank armor - then it coats the dead tank with radioactive dust. How harmful this radioactive dust is, is a matter of some debate but many believe that one time exposure caused by climbing on to a dead tank would not be harmful to an individual. Repeated exposure, such as that which would be encountered by salvage crews, could have serious long term effects and thus such crews are required to wear protective clothing when working with vehicles destroyed by DU ammo.
Of recent concern has been how far this radioactive powder can spread through the air or by water systems and what type of concentrations can result.
For the record, DU is used only in cannon, specifically tank guns and aircraft-mounted anti-tank guns. There aren’t any soldiers walking around with a pocket full of uranium bullets. (The smallest such rounds are about the size of an old milk bottle.)
Boy, that would change grouse-hunting just a bit, eh?
DU is also used in tank armor, as it can stop everything else. But when it does explode, boy howdy. I wouldn’t want to inhale that stuff.
I’m not familiar with the conventions vs. using nukes/radioactive materials. Is it legal to use radioactive weapons against people? Could we just spray uranium dust over our enemies, or would the rest of the world frown at that? And if that’s bad, isn’t DU skirting a fine line?
DU is indeed DEPLETED Uranium, meaning it’s “out of gas” radiocativity-wise. One of the physicists out there can tell us to what degree any radioactive “fumes” remain in the “gas tank”, but as far as I know there are little to none.
But… I had the dubious privelige of working with DU at one time in the form of counterweights on aircraft control surfaces (S-3, if you must know). They used it in that application and in ammunition because of its density. I was always amazed about how heavy apparently small pieces of DU were. A piece about the size of the lid of a coffee can weighed about like the whole can when it was full. I believe it’s at least as dense as lead, but is definitely harder and is machineable. Because it doesn’t “squash” like lead does, it is preferrable for shooting through things like steel armor on tanks. When working with DU in the aircraft industry, there were OSHA type precautions one had to observe that had to do with handling and disposing of the material. But these were because it is toxic if ingested or taken into the blood, and not because radioactive. However, the precautions against its toxicity were nowhere at all as extensive as that for the beryllium brakes discs on the same aircraft. Basically, the DU precautions were: don’t eat it (like that was remotely feasible!), wear gloves when you handle it, don’t cut yourself with it, and dispose of any scraps in speccial containers. On the other hand, you had to work with the beryllium brakes in a specially sealed environment and bunny-suit, etc.
I am not an industrial hygenist, but it seemed to me then and still seems now that the hazards from DU were not all that great. Given the other precautions observed for other materials, I beleive it is NOT a case of government denial and cover-up of some huge hazard; the hazard simply is not that great.
One could TRY to make the case that DU rounds constitute “poison” ammunition and as such are banned by the various Geneva Conventions, but said conventions only ban poison small arms bullets and not anti-tank rounds. No one ever thought in terms of “poisoning” a non-living object such as a tank. In any case, the intention of the laws are to ban ammunition that intentionally cause toxic effects as a major goal. Clearly, this is not the case with DU rounds. The “proof” that DU rounds have caused any toxic effects —direct or indirect— still is dubious at best. Trying to make a case against DU as a “poisoned bullet” is thus way more remote than making a case for lead in bullets as poison (and of course lead bullets have been used since day one in guns of all types).
Well, it’s not exactly “out of gas radioactivity-wise”, but it’s a lot less radioactive than natural uranium.
Depleted uranium is what’s left over after the natural uranium has gone through the enrichment stages to concentrate U235 and U234 for weapon or reactor use. Since U235 constitutes less than 1% of natural uranium, concentrating this to 80% for weapons grade uranium leaves ENORMOUS amounts of “depleted” uranium behind, meaning that it’s 1% of U235 has mostly been stripped out.
Depleted uranium is simply U238, which is an alpha particle emitter with a half-life of 4.51 billion years. Also, with the removal of the 1% of U234 and U235, depleted uranium becomes about half as radioactive as natural uranium.
From what I gather, the real danger from depleted uranium isn’t due to the minor radioactivity, but due to it’s chemical toxicity, which is similar to other heavy metals.
so it’s not that they’ve found a way to turn off the radioactivity (which I thought would be impossible with uranium), as that what’s called DU is really the U-238 isotope, which is less radioactive? do I understand that right? [have pity on my ignorance - physics 101 was a long time ago)
ALL KNOWN isotopes of Uranium are radioactive. For an equal mass and density of material (and I’m sure I may be making a slight assumption here), the difference in the level of radioactivity lies in both the half-life of the particular isotope (how often radiation is emitted), and the method of radiation emission (alpha, beta, or gamma).
Una, who has a piece of Uranium mineral sitting on her desk at home.
Yes, AFAIK when one speaks of “depleted Uranium” they are speaking of U-238. Typically, four different materials are suitable for fission by thermal neutrons - U233, U235, Pu239, and Pu241. U238 is fissionable by fast neutrons, and has a half-life of 4.51 billion years. When it decays, it does so via emission of alpha particles, which are pretty weak and harmless unless inhaled or ingested.
I hope Nuke E’s will verify what I say - I’m not an expert in this area, but took my info from “Basic Nuclear Engineering”, Arthur R. Foster and Robert L. Wright.
[sup]238[/sup]U has a half-life of about 4.47 gigayears, and almost always (with a probability of about 99.99%) decays through emission of an alpha with an energy of 4.27 MeV. Alphas aren’t penetrating at all, although if my memory can be trusted (which it can’t), I believe that the “Q” factor of alpha radiation is about 30. Currently, about 99.274% of naturally occurig uranium nuclei are isotope 238.
[sup]235[/sup]U has a half-life of about 704 megayears, and almost always undergoes alpha decay; the emitted alpha has energy 4.679 MeV, close enough to that of its sister. Its natural abundance is 0.72% at the moment.
[sup]234[/sup]U has a half-life of 246 kiloyears, and decays by emiision of an alpha of energy 4.859 MeV. It can be formed by beta decay of [sup]234[/sup]Pa; its natural abundance is only 0.0055% of uranium nuclei, however.
Someone else can do the arithmetic to decide how much the radioactivity of uranium is decreased after the [sup]235[/sup]U fraction is separated by enrichment. My SWAG, however, is that the risk of death from having a chunk dropped on one’s head is several orders of magnitude higher than the risk of contacting leukemia from breathing the same weight of uranium ash.
What this means, in pratical terms, is that your skin is more than adequate shielding against the normal mode of U238 decay. However, should you ingest U238, your internal tissues are not suffcient shielding, and you are then exposed to ionizing radiation 30 times more dangerous than that of Co60 (the previously mentioned ‘Q’ factor). U238 is also, as are most heavy metals, toxic.
Thus, if your U238 comes in big, happy chunks, well cool, then. If your U238 comes in microscopic fragments (such as one might get from a Hyper-Velocity Depleted Uranium Monolithic Penetrator striking armor), you then have a high risk of ingesting/inhaling a killer. For this reason, spraying DU dust over enemy troops would be considered one the worst forms of War Crime, making the perpetrator an international pariah, at the least. Oh, and the dust would render large chunks of the landscape economically unusable.
Hi guys. Someone alerted me to this thread over on my message board for my comic strip, “Nukees.” What Tranquilis said above is essentially correct, although I wouldn’t call spraying DU dust “one of the worst forms of War Crime.” Spraying a heavy metal in dust form onto people is certainly not something I’d want to have happen to me, but I can think of a lot of other things sprayed during wartime that would be far worse. 
Also, injesting Uranium is not that big a deal. Only inhaling it is bad. Your body won’t absorb injested Uranium. Alpha rays will do damage while the DU is in the body, but it doesn’t stay in the body long if you eat it, and the half-life is so long, it’s not very radioactive at all. The toxicity as a heavy metal is much worse, which is only an issue if inhaled. Frankly, DU artillery rounds are the least of your troubles if you’re in the military.
It brings up an interesting story that happened a few years ago. Ralph Nader was going off on his crusade, saying that Plutonium was the “most toxic substance on the planet.” A Nuke E came forward (I forget which one) and publicly challenged Nader. The scientist said, “I’ll eat a gram of Plutonium if you’ll eat a gram of arsenic.”
I thought it was the funniest thing ever, as isn’t Nader typically the one to make these kinds of cute challenges? As far as I know, Nader completely ignored the challenge.
It was Bernard Cohen, from Pitt, who offered to eat as much plutonium as Nadar would eat pure caffeine.
I started a thread that’s pulling in people from other boards? I feel so proud, yet humble.
(Oh, wait - the same thing happened last year - with the Left Behind guys invading us when they found our location - and this guy seems friendly, but may have nuclear weapons - run, run!)
Remember, only the survivors of the conflict live to complain about the DU weapons. The ones who were killed by enemies who were “saved” by the conventional payloads aren’t around to complain.
And anyway, isn’t virtually everything in the military incredibly unsafe? How many paratroopers are expected to be paralyzed or dead in a given drop? How many rifle backfires are expected to be deadly? How much of the infantry is epxected to be physically run over by tanks? War isn’t safe.
Alpha particles? I laugh at alpha particles! I’ll inhale a lungful of ‘em and come out singin’ the Chipmunks.
Depleted uranium rocks because it does what it is designed to do: kill tanks. I’ve never had to mess with an angry tank, but I’ve read enough accounts and talked to enough people to say that if you can bust a tank with anything, there’s a grunt who will thank you for it now, and to hell with tomorrow. That’s another day of living.
Vermont SIRI has this toxicity data sheet on mixed tetravalent/hexavalent uranium oxides (my SWAG is that uranium ash produced by dU penetrators is almost entirely hexavalent, though).
Question frequently asked of Baby Nucs (Navy usage: Not yet qualified nuclear-trained personnel) by Qualification Boards:
Q) You’ve got four cookies, a nuetron cookie, an alpha cookie, a beta cookie, and a gamma cookie. You’ve gotta eat one, hold one, pocket one, and throw one. What do you do with each cookie?
A) Hold the alpha cookie in your hand, where it can’t hurt you, put the beta cookie in your pocket, where your clothes will protect you, eat the gamma cookie, as nothing you’re going to be able to do (practically) is going to protect you, and throw the nuetron cookie (far) away, as it’s the most dangerous.
Okay, call me a goofball, but what is a “nuetron cookie”? I’m assuming it’s a cookie made only of neutrons, which is suppose would be dangerous since, if I have my speculative physics worked out, that would make it neutronium … the substance neutron stars are made out of. Which would be too dense to lift, and too dense for the floor to support, and too dense for the crust and mantle of the earth too support, and would thus mostly likely penetrate to the core. So maybe that’s not what you mean. I prefer toll house anyway.