# Is depleted uranium as radioactive as non-depleted?

**URL:** https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067
**Category:** Factual Questions
**Created:** [September 12, 2002, 1:56am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067 "2002-09-12T01:56:23Z")
**Posts on this page:** 20
**Page:** 1

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### Author: ![SmackFu](https://avatars.discourse-cdn.com/v4/letter/s/53a042/32.png) [@SmackFu](https://boards.straightdope.com/u/SmackFu)
#### Post date: [September 12, 2002, 1:56am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/1 "2002-09-12T01:56:23Z")

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I saw [this report](http://abcnews.go.com/sections/wnt/DailyNews/sept11_uranium020911.html) on ABC News about smuggling a depleted uranium sample out of Europe into the US. They made a big deal about this being very similar to an actual bad thing to smuggle: "In other words, to the to the human eye or to an X-ray scanner, the depleted uranium would look the same as an actual radioactive shipment. " But it seems to me that the primary way to detect this particular kind of thing would be by the radiation it gives off.

Which leads back to the original question: is depleted uranium as radioactive as high-grade material?

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### Author: ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)
#### Post date: [September 12, 2002, 2:19am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/2 "2002-09-12T02:19:04Z")

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A brief Google search turned up [this article](http://www.who.int/inf-fs/en/fact257.html) which states that depleted uranium contains about 99.8% U-238 (pretty safe stuff) and the rest is the more dangerous stuff (mostly U-235). The radiation from deplted uranium is about 60% of pure natural uranium. And it’s less than 1% from pure U-235.

So no, depleted uranium is far less radioactive than weapons grade uranium. But since depleted uranium still contains a bit of U-235, it gives off the same kind of radiation as U-235. It’s definitely a concern that they didn’t catch a lump of material which looks like uranium (esp. to an X-ray scanner) and gives off the same type and energy radiation as U-235, albeit in much lower dosage.

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### Author: ![Yeah](https://avatars.discourse-cdn.com/v4/letter/y/dbc845/32.png) [@Yeah](https://boards.straightdope.com/u/Yeah)
#### Post date: [September 12, 2002, 3:02am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/3 "2002-09-12T03:02:02Z")

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'is depleted uranium as radioactive as high-grade material?"

“Depleted” uranium is uranium that is depleted of radioactivity (although a bit remains).

Natural uranium as it comes out of the gound is a mixture of U-235 and U238 and isn’t good for much. However, you can, at great expense, partially separate out the radioactive U-235 from the U-238. You can use the stuff enriched in U-238 for bombs and power generation and you can use the stuff depleted of U-238 for things that call for metal more dense than lead.

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### Author: ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)
#### Post date: [September 12, 2002, 4:20am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/4 "2002-09-12T04:20:53Z")

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And to armor M-1 Abrams tanks.

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### Author: ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)
#### Post date: [September 12, 2002, 4:26am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/5 "2002-09-12T04:26:46Z")

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Yeah is correct, except that U-235 is the radioactive, dangerous stuff, and U-238 is the stable, boring stuff.

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### Author: ![Dr.Lao](https://avatars.discourse-cdn.com/v4/letter/d/2bfe46/32.png) [@Dr.Lao](https://boards.straightdope.com/u/Dr.Lao)
#### Post date: [September 12, 2002, 4:51am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/6 "2002-09-12T04:51:56Z")

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Both uranium 238 and uranium 235 are radioactive. Neither is very highly radioactive. 238 has a half-life of 4.5 billion years and 235 has a half-life of 713 million years. So, 235 is about 6 times more radioactive for a given mass.

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### Author: ![Cerowyn](https://avatars.discourse-cdn.com/v4/letter/c/82dd89/32.png) [@Cerowyn](https://boards.straightdope.com/u/Cerowyn)
#### Post date: [September 12, 2002, 5:13am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/7 "2002-09-12T05:13:54Z")

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> [@](#):
>
> \*Originally posted by Yeah \*  
> **Natural uranium as it comes out of the gound is a mixture of U-235 and U238 and isn’t good for much.**

Actually, that’s not true at all. The CANDU reactor, for instance, uses un-enriched uranium as fuel.

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### Author: ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)
#### Post date: [September 12, 2002, 5:20am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/8 "2002-09-12T05:20:41Z")

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> [@](#):
>
> \*Originally posted by scr4 \*  
> **The radiation from deplted uranium is about 60% of pure natural uranium. And it’s less than 1% from pure U-235.**

Sorry, that second part is not from the cite and, now that I think about it, is incorrect. It’s higher but I don’t have the numbers off hand.

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### Author: ![PosterChild](https://avatars.discourse-cdn.com/v4/letter/p/e274bd/32.png) [@PosterChild](https://boards.straightdope.com/u/PosterChild)
#### Post date: [September 12, 2002, 6:04am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/9 "2002-09-12T06:04:55Z")

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So would it be easier to enrich depleted uranium than natural uranium?

PC

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### Author: ![Bryan\_Ekers](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bryan_ekers/32/183_2.png) [@Bryan\_Ekers](https://boards.straightdope.com/u/Bryan_Ekers)
#### Post date: [September 12, 2002, 6:35am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/10 "2002-09-12T06:35:20Z")

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“Enriched” is kind of a misnomr, since it implies somthing has been added. What it really means is that the Uranium ore (aka pitchblende) which is normally almost all U238 and only partly U235 has been put through a refinement process so that some (or even most) of the U238 has been removed, leaving a higher percentage of the party-down U235, hence making the product “richer”.

Uranium (particularly the boring old U-238) is the most massive naturally occuring elemen, and is thus used for armor and shells used to pierce armor.

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### Author: ![SenorBeef](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senorbeef/32/2220_2.png) [@SenorBeef](https://boards.straightdope.com/u/SenorBeef)
#### Post date: [September 12, 2002, 9:33am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/11 "2002-09-12T09:33:00Z")

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> [@](#):
>
> \*Originally posted by Enola Straight \*  
> \*\*And to armor M-1 Abrams tanks. \*\*

Actually, they don’t use depleted uranium in the armor, I believe - just the ammunition. Chobham armor is simply steel with ceramic plates, I believe.

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### Author: ![scm1001](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@scm1001](https://boards.straightdope.com/u/scm1001)
#### Post date: [September 12, 2002, 9:53am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/12 "2002-09-12T09:53:13Z")

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there is information on depleted uranium at [http://www.vbs.admin.ch/ls/e/bg\_info/du/du\_study\_print.pdf](http://www.vbs.admin.ch/ls/e/bg_info/du/du_study_print.pdf)  
essentially depleted uranium is only about 20% less radioactive than natural uranium - but natural uranium is pretty safe to handle on a short time scale.

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### Author: ![Jman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jman/32/4416_2.png) [@Jman](https://boards.straightdope.com/u/Jman)
#### Post date: [September 12, 2002, 10:48am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/13 "2002-09-12T10:48:48Z")

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Senor Beef…they definitely use depleted uranium in the armor of M-1 tanks.

Jman

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### Author: ![Yeah](https://avatars.discourse-cdn.com/v4/letter/y/dbc845/32.png) [@Yeah](https://boards.straightdope.com/u/Yeah)
#### Post date: [September 12, 2002, 11:37am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/14 "2002-09-12T11:37:59Z")

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'is depleted uranium as radioactive as high-grade material?"

“Depleted” uranium is uranium that is depleted of radioactivity (although a bit remains).

Natural uranium as it comes out of the gound is a mixture of U-235 and U238 and isn’t good for much. However, you can, at great expense, partially separate out the radioactive U-235 from the U-238. You can use the stuff enriched in U-238 for bombs and power generation and you can use the stuff depleted of U-238 for things that call for metal more dense than lead.

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### Author: ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)
#### Post date: [September 12, 2002, 11:44am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/15 "2002-09-12T11:44:09Z")

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Sorry, folks, but you’ve got it wrong. “Depleted” uranium _is_ radioactive. It has several decay routes, but it emits radiation of various kinds. That’s how Henri Becquerel was able to use it to expose film – the radiation didn’t all come from the minuscule portion of U-235.

The difference is that U-238 isn’t fissile – it won’'t support a chain reaction. You can’t build a bomb out of it. You can, however, expose people to radiation from it, and some have held that some illnesses from the Gulf War was due to radiation exposure from depleted uranium rounds.

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### Author: ![Yeah](https://avatars.discourse-cdn.com/v4/letter/y/dbc845/32.png) [@Yeah](https://boards.straightdope.com/u/Yeah)
#### Post date: [September 12, 2002, 11:48am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/16 "2002-09-12T11:48:41Z")

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Oops. Sorry about the double post.

This site has a good diagram illustrating the enrichment process:  
[http://www.nuclear.gov/uranium/facts.html](http://www.nuclear.gov/uranium/facts.html)

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### Author: ![galen](https://avatars.discourse-cdn.com/v4/letter/g/ecc23a/32.png) [@galen](https://boards.straightdope.com/u/galen)
#### Post date: [September 12, 2002, 2:21pm UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/17 "2002-09-12T14:21:13Z")

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What is truly outrageous is that there is now tons of this stuff littering the landscape anywhere the US goes to war, which is about once every five years. In Yugoslavia and Iraq, people will be breathing dust laced with uranium till the end of time. Depleted uranium ammo hould be banned. It’s use should be a war crime. It is much worse than poison gas which eventually dissapates.

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### Author: ![Armilla](https://avatars.discourse-cdn.com/v4/letter/a/e19b73/32.png) [@Armilla](https://boards.straightdope.com/u/Armilla)
#### Post date: [September 12, 2002, 3:38pm UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/18 "2002-09-12T15:38:21Z")

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I believe Uranium is an alpha particle emitter, so shielding its radiation while in transit shouldn’t be that much of a problem. Alpha particles can be stopped by something as trivial as a piece of paper ([http://www.hps.org/publicinformation/ate/q1094.html](http://www.hps.org/publicinformation/ate/q1094.html)) so simply packing it in a crate or suitcase will make it difficult to detect using something like a standard G-M tube.

The radioactive danger Uranium really presents is when it is ingested as particulates. Once inside a body its radiation can only be absorbed by the cells around it, inevitably leading to progressive damage. Added to this is the fact that it, like other heavy metals, is poisonous in its own right.

It has been suggested that Gulf War Syndrome is, among other things, a combination of the radiological and chemical poisoning effects of Uranium.

The danger from depleted uranium munitions on the battlefield is that, subjected to high forces, the projectiles shatter, explode and generally spread these dangerous particulates around. Uranium can also catch fire, making it very efficient at creating dust and other hazardous byproducts.

The “dirtiness” of DU weapons is still a subject of hot debate. I think it’s likely that, in the end, they will be banned, but as to when this will happen, I can’t say.

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### Author: ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)
#### Post date: [September 12, 2002, 3:44pm UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/19 "2002-09-12T15:44:22Z")

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**galen** : That’s as may be, but GQ isn’t the place for ranting.

A friendly reminder from a fellow member.

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### Author: ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)
#### Post date: [September 13, 2002, 4:46am UTC](https://boards.straightdope.com/t/is-depleted-uranium-as-radioactive-as-non-depleted/128067/20 "2002-09-13T04:46:45Z")

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Even before the discovery of radiation, natural uranium had some uses. For one thing, it’s used as a pigment in some pottery glazes, giving a nice yellow color. For another, it’s very dense, which can be useful at times. Natural uranium is found all over the world, and it would be difficult to keep it out of the hands of any particular group.

It _is_ radioactive, and it’s dangerous both due to that and it’s chemical properties (almost all of the heavy metals are poisonous to some degree). With proper precausions, though (mostly just a matter of not ingesting the stuff), it can be handled safely, and while it could be used as a weapon, it wouldn’t be a very effective one.

Enriched uranium has a higher proportion of the more reactive and fissile U235. This can be used to make nukes, and is definitely something we want to keep out of the hands of terrorists and rogue states. Fortunately it’s difficult to produce.

What’s left over after you’ve enriched the uranium for bombs or reactors is depleted uranium. This has a higher proportion of the less active U238. It is in every way as safe or safer than natural uranium. It’s chemically just as poisonous, but then, lead is chemically poisonous, too, and lead doesn’t cause all that much worry. It’s less radioactive than natural uranium, and it would be harder to get U235 (the weapons isotope) from it. In other words, not much of a cause for worry.

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