This is so basic it shouldn't need to be pointed out, but it seems to me this simple point nullifies many of the pro-DU arguments. I will cut and paste a comment I found at this Wired Magazine article that made the point hit home for me.

http://www.wired.com/news/wireservice/0,...=rss.index

Can anyone see any problem with this argument?

I guess not.

So pass it on.

"DU is 60% as radioactive as natural uranium". Technically true, but uranium can't be found in "pure" form in nature. It is mined from rocks containing about 0.1% uranium oxide. On the other hand, depleted uranium shells used by the U.S. Army contain 96.5% uranium. That explains why the alloy used in DU shells is actually hundreds of times more radioactive than any uranium ore found in nature."

Uranium is pure and found in nature. The depleted uranium which was first used in weapons and ammo in Operation Desert Storm and is used today is NOT natural but MAN MADE, containing Uranium-236 isotopes which do NOT occurr in nature nor can it be mined from rocks!

Know your facts before making a fool of yourself in front of others!

I have been looking deeper into this question. I just wrote a blog entry on it here: Yellowcake Fever

And a previous one here: Re-enrichment and the price of DU

According to my math, a 1 kg DU shell should contain about as much U-235 as a 1 kg brick of the richest yellowcake. The enrichment process only removes about half to two-thirds of the U-235.

Since the DU shell is made of 99% pure metallic uranium, that remaining third of the U-235 makes it just as deadly as the most concentrated "natural uranium" known to man.

Of course, this only applies if the DU shell (or the yellowcake) is pulverized to increase its surface area. This releases the radiation because it gets rid of the self-shielding effect. It will also release the radiation from all the transitional nucleotides created inside a DU shell due to the self-shielding, such as radon.

There is a good video by Dr. Rosalie Bertell in which she explains this very well. youtube.com/watch?v=WgQ79-oDX2o

From a radiation point of view, the problem with uranium ore, is not so much the uranium, but rather its decay products which have had thousands, if not millions of years to build up. These decay products have a much higher radioactivity per gram than uranium, and are the major radiation hazard with uranium mining.

Now, chemically purified uranium, which has had all of these dangerous decay products removed, is quite safe as far as radioactive materials go. It still has U-235 and U-234, which is much more radioactive than U-238, but on the whole is not too bad. Interesting enough, U-234 makes up 0.0054% of natural uranium, but since its half-life is only 244,500 years, it makes up almost 50% of the radioactivity. Natural uranium, that is freshly chemically separated has about 50,000 disintegrations per second per gram (50,000 Bq/g). Depleted uranium, which has had a lot of its U-235 and U-234 removed only has approximately 14,000 Bq/g.

So, DU is much safer than natural uranium from a radiological perspective. Both natural and depleted uranium have the same chemical toxicity. In fact, the chemical toxicity is generally more hazardous; the only time when radiological toxicity is greater than chemical is inhaled non-soluble forms (if I recall correctly).

Godschild does make an interesting point. Unfortunately, he is up shit creek without a paddle, as most DU comes directly from the UF6 enrichment processes, and never sees a single atom of U-236. There is some DU which comes from reprocessing, which is contaminated with transuranics and U-236, but the degree of contamination should be so limited, that the impact on toxicity is of the order of 1%.

Of course, it is all well an good to say that these contaminating elements are kept to a minimum, but if presented with scientific evidence that the US has used what I like to call "not quite so depleted uranium" I would not take much convincing. The US do not have a very good track record in war, so I would not put it past them to use seriously contaminated uranium based rounds. However, having said that, actual DU is not very toxic.

Some more random information:
I believe that kinetic penetrators are predominately uranium, but I think they are alloyed with some tungsten ~1%. I do not know what adding tungsten does, but I am sure it improves it as a weapon.

Beagle you mean nuclide not nucleotide.

DU is about as chemically toxic as lead.

I have not seen any research that indicates that uranium has DNA seeking properties, but alpha particles usually have a range of the order of a cell, so as long as it decays in the cell, it will be doing damage. I am also not totally familiar with all of the research, but it is a topic I have become quite interested in recently, because of the amount misinformation being put forward by anti-DU "activists".

Does the radioactivity of DU do damage to cells and DNA. It absolutely does. However, a lot of this damage is repaired. There are in fact some people in the radiation protection field that think that low doses of radiation have beneficial effects as it keep the DNA repair mechanisms "fighting fit". I am not sure about the beneficial aspects of ionising radiation, but the amount of radioactivity people are going to be exposed to due to DU penetrators used in war has a very minimal impact.

Uranium does need to be aerosolised and to be in very high concentrations to be an immediate threat to life. The only likely circumstance where someone would be in a situation where they could breath in enough uranium is by being inside a tank struck with anti-tank DU penetrators. Now being exposed to uranium is hazardous, but being in a tank that just had the crap shot out of it by a 30mm rotary cannon, is much, much more hazardous.

I not even remotely convinced that DU had much on an impact on gulf war veterans, I suspect that burning Iraq's chemical weapons, and the "not quite so well tested" vaccines and maybe the oil fires (although an HP-turned-epidemiologist friend of mine has suggested the effect of the oil fires is also a beat up) are a much better place to start looking.

I acknowledge that DU is toxic, and I certainly do not want it fired at me. The DU penetrators do produce some amount of environment contamination, and despite what some people say it does not last forever, but rather become non-soluble and exists the food/water chain, or leaches away to background levels over time. My main thrust is that there are a lot of "activist" out there who have a very poor grasp of the truth and spread this misinformation because they feel they are doing the "right" thing.

Personally, I think people who do not use their intellect or base their opinions on facts, but rather are swayed by emotion and are easily convince of anything that is scary should shut up and go away. Failing the shutting and up and going away strategy, they should concentrate their efforts on something that is a real hazard, like man made climate change. The facts in favour of climate change are very strong, and the consequences are much more dire.

I think you're right that the activists feel they are doing the "right" thing as you say. Thanks for your partial support there, but I'll need to hear more before shutting up and going away and, I think, so will all the others.

You may never return back to this board to read this, but I would like to hear more of your eloquence on the matter of radiation. My question is whether or not comparing different substances "radioactivity" in Bq/g isn't like comparing apples and oranges. It is a simple matter to find references saying that internal alpha radiation is far more damaging that beta or gamma. But to say DU is safer than yellowcake by 50,000 Bq/g to 14,000 Bq/g is disingenuous regardless of how much hi-rad stuff is present because it is the DU that is pyrolized or whatever on the battlefields and it is an alpha emitter. And if it's so safe outside the body, why don't we make paperweights with it, huh?

So, let's say a microgram or so of "clean" DU gets into a cell and sits around for years giving off a few alpha particles every minute. Isn't it logical, based on basic knowledge of cellular biology, to admit that it is entirely possible for ONE of these emissions to create a cancerous mutation? Isn't it logical to assume that in a continual bombardment like this, some strands of DNA will indeed get hit and some amount of damage will be caused. And if the exposure level that caused this cell to be invaded by a dangerous guest were higher, more and more cells in its vicinity would be similarly affected and this would raise the risk of cancer or developmental abnormalities higher in a synergistic fashion?

So how wise is it really to created large amounts of fine uranium dust around the desert? You feel that only people very near the tank would suffer, but you're not a cell biologist, are you? I still say you have a faith in your model that is typical of most scientists. Yet history shows, most of them had unwarranted faith. You mention not having heard of any DNA-seeking behavior of uranium. That's not a good cornerstone for your faith I would suggest. People don't find what they don't look for. DNA-binding has recently been demonstrated.

And now some research has been done showing GWS sufferers show chromosonal damage similar to that caused by alpha radiation. Discovery Channel paid for the study. You might want to check it out here.

"DU is 60% as radioactive as natural uranium". Uranium is pure and found in nature. The depleted uranium which was first used in weapons and ammo in Operation Desert Storm and is used today is not original but artificial, containing Uranium isotopes which do not occur in nature nor can it be mined from rocks!