Naked Science Forum

General Science => General Science => Topic started by: chris on 25/01/2008 13:03:59

Title: What is Depleted Uranium?
Post by: chris on 25/01/2008 13:03:59
What is depleted uranium, how is it manufactured and what are its uses and abuses? Is it environmentally hazardous?

Chris
Title: What is Depleted Uranium?
Post by: another_someone on 25/01/2008 20:00:32
Natural uranium has a mixture of isotopes, the primary ones being 238 and 235U.

235U is capable of fissioning, and this is used to make an atomic bomb.  In the natural world, most of the 235U that once was has already fissioned or otherwise transmuted into other elements, so what is left is too sparsely spread to naturally explode (which is quite fortunate really).

In order to make a working atomic bomb (or even just most types of nuclear reactors for a power station) using 235U, you need to concentrate the amount of naturally occurring 235U.  If you increase the concentration of 235U in the material you will use for a reactor or a bomb, you will inevitably have depleted the amount of 235U left in the remaining uranium you have, and this is 'depleted uranium' (i.e. uranium that is depleted in 235U, but consequently enriched in the other isotopes of uranium - in particular, 238U).

As it happens, 238U has a half life that is in the order of magnitude of the age of the Earth (a half life of about 4.4 billion years), so it is only very weekly radioactive (and since that radiation is predominantly alpha radiation, it is easily stopped with the minimum of shielding - but in fact many people actually regard 238U as safe to handle without shielding).  This compares with 700 million years half life for 235U, which is still a long half life (and so less radioactive than many other substances), but is nonetheless more radioactive than 238U.

Uranium is one of the densest materials known (certainly, the densest that can easily be used, and denser than lead).  Since depleted uranium is less radioactive, and cannot be ordinarily fissioned, it is considered fairly safe to use in contexts where very high density is of an advantage (e.g. it is used in some forms of ammunition in place of lead, and in some weights for inertial guidance system, and in some types of radiation shields).

Uranium is a heavy metal, and like many other heavy metals, is chemically toxic (just as lead is), and this probably presents a greater environmental danger than the small levels of radiation it emits.  This is particularly the case with depleted uranium ammunition, which will often spontaneously burst into flame or splatter as an aerosol when it hits its target, thus making it possible that anybody close by could breath in uranium aerosol droplets, or uranium oxide dust.

It is also possible to convert 238U into plutonium within a fast breeder reactor, and from this create a plutonium based atomic bomb.
Title: What is Depleted Uranium?
Post by: chris on 29/01/2008 09:00:17
Thanks George, for that comprehensive and clear answer.

Chris
Title: What is Depleted Uranium?
Post by: Andrew K Fletcher on 04/06/2008 09:09:23
War-related birth defects in Fallujah

Press TV
Friday, May 30, 2008

Families in Fallujah are calling for an investigation into the rise of birth defects after the US used phosphorus over the Iraqi city in 2004.

They have raised concerns about the weapons used by American forces in 2004, including constant bombardment with uranium depleted artillery shells and other depleted uranium ammunition- when Fallujah suffered the heaviest blitze following the overthrow of the Saddam regime of the entire war in Iraq.

Hikmat Tawfeeq, deputy chairman of the Fallujah-based human rights group Al-akhiyar said: "We have around 200 cases of deformities recorded by our society. Most of these cases are birth deformities which have arisen after the bombing of Fallujah."

(Article continues below)


Campaigners say officials are reluctant to speak out publicly because of US pressure but at Fallujah's children's hospital one doctor told Sky News in the past month she has seen one or two cases of birth deformities every day.

An opthalmologist said he deals with four or five cases of newborn babies every week suffering from some form of eye deformity.

At one of the cemeteries in Fallujah, undertaker Mahmoud Hummadi said he usually buries four to five bodies of newborns every day and most of them are deformed.

Fallujah today still bears the scars of a time when it represented the backbone of the Sunni insurgency - a power-base America decided it had to break.

April and November 2004 saw some of the heaviest bombardments of the war in Iraq, including the controversial use of white phosphorous.

It is a highly flammable material which ignites when it comes into contact with oxygen, causing severe burns.

In a statement to Sky News the US military said it had used white phosphorus in Fallujah but primarily as a smokescreen and not as an incendiary weapon.

The families say doctors have raised concerns to them about what kinds of materials were used by the Americans in order to achieve their military goals.

Fatima Ahmed is three years old. Small and lifeless she barely moves, burdened by two heads on her tiny frame.

Her mother Shukriya says doctors have been unable to diagnose exactly what has caused Fatima's condition.

But her father Jassim, when asked who he held responsible for his daughter's condition, said: "It's because of the war - it's the flagrant aggression they launched against us. What they dropped in Fallujah God knows."

http://infowars.net/articles/may2008/300508Fallujah.htm
Title: What is Depleted Uranium?
Post by: rosalind dna on 04/06/2008 11:40:41
What about the people, who are still suffering for Depleted Uranium landmines from the first Gulf War also from the Balkan wars in the 1990s?

Also it's completely denied as far as I can recall by the said governments, Britain and the USA too.
We had John Major and Tony Blair in power here then but in the US
it was Presidents, George Bush senior, Bill Clinton.
Title: What is Depleted Uranium?
Post by: Bored chemist on 04/06/2008 19:37:18
Is there any evidence that depleted uranium causes birth defects?
It is certainly true that they happen without depleted uranium- they happened before the stuff was ever made.
Is there a statistically significantly higher incidence in these areas. Is there some way to rule out any of a large number of other potential causese- maternal stress would be an obvious one but there are plenty of others.

Sthis is a threda about depleted uranium on a scientific site. Oughtn't the replies stick to well evinced data about the stuff rather than poltics?
Title: What is Depleted Uranium?
Post by: Andrew K Fletcher on 04/06/2008 20:52:16

Only the evidence that is before your eyes if you care to delv deep enough.

By Environment Correspondent Alex Kirby
The controversy over the reported dangers of depleted uranium (DU) has intensified, with a Canadian study said to show "unequivocal" evidence of damage to health.
http://news.bbc.co.uk/1/hi/sci/tech/431817.stm


Title: What is Depleted Uranium?
Post by: TheHerbaholic on 06/06/2008 13:18:38
Isnt uranium the stuff the mad scientist steals off the terrorists in back to the future lol
Title: What is Depleted Uranium?
Post by: chris on 06/06/2008 23:53:28
I thought it was plutonium?
Title: What is Depleted Uranium?
Post by: Madidus_Scientia on 07/06/2008 01:28:30
Yes it was, Doc.
Title: What is Depleted Uranium?
Post by: Bored chemist on 07/06/2008 17:53:12
Andrew, the first post (youtube) has been taken down. Describing it as "the evidence that is before your eyes if you care to delv deep enough." seems unhelpful.

The second includes this
"But the Newfoundland research has not yet been peer-reviewed, which worries Tony Duff, secretary of the Gulf Veterans' Association.

He told BBC News Online: "I think it is interesting. But until it has been reviewed, we cannot draw any firm conclusions.

"I do not want to raise people's hopes by claiming it is definitive until we know that it is."
"
The fact that there's detectable uranium in someone's urine doesn't mean much. Analytical chemistry is a sophisticated science. Generally speaking, if something is present it can be found and measured.
That doesn't mean it has any biological effect.
The average concentrtion of uranium in the eath's crust is about 6 parts per million- roughly a quarter of an ounce in each ton.
Some of that is inevitably going to end up in the body.
So what?
Title: What is Depleted Uranium?
Post by: Andrew K Fletcher on 12/06/2008 17:17:07
http://www.irak.pl/Stop/EXTREME%20BIRTH.html

Soaring birth deformities and child cancer rates in Iraq
By James Cogan
10 May 2005
http://www.wsws.org/articles/2005/may2005/iraq-m10.shtml
Six years ago, the College of Medicine at Basra University carried out a study into the rate of cancer among children under the age of 15 in southern Iraq from 1976 to 1999. It revealed a horrific change between 1990 and 1999. In the province of Basra, the incidence of cancer of all types rose by 242 percent, while the rate of leukaemia among children rose 100 percent. Children living in the area were falling ill with cancer at the rate of 10.1 per 100,000. In districts where the use of DU had been the most concentrated, the rate rose to 13.2 per 100,000.

The results were cited at the time in campaigns to end the UN-imposed and US-enforced sanctions against Iraq, which were held responsible for the death of as many as 500,000 Iraqi children from malnutrition and inadequate medical treatment.

The study noted: “Most doctors and scientists agree that even mild radiation is dangerous and increases the risk of cancer. The health risk becomes much greater once the [DU] projectile has been fired. After they have been fired, the broken shells release uranium particles. The airborne particles enter the body easily. The uranium then deposits itself in bones, organs and cells. Children are especially vulnerable because their cells divide rapidly as they grow. In pregnant women, absorbed uranium can cross the placenta into the bloodstream of the foetus.

“In addition to its radioactive dangers, uranium is chemically toxic, like lead, and can damage the kidneys and lungs. Perhaps, the fatal epidemic of swollen abdomens among Iraqi children is caused by kidney failure resulting from uranium poisoning. Whatever the effect of the DU shells, it is made worse by malnutrition and poor health conditions....

“Iraq holds the United States and Britain legally and morally responsible for the grave health and environmental impact of the use of DU ...” (A version of the report is available at: http://www.iacenter.org/depleted/du_iraq.htm).

Terrible as these results were, the last six years have witnessed a further rise in the number of children under 15 falling ill with cancer in Iraq. The rate has now reached 22.4 per 100,000—more than five times the 1990 rate of 3.98 per 100,000.

Title: What is Depleted Uranium?
Post by: Bored chemist on 12/06/2008 18:47:57
"Whatever the effect of the DU shells, it is made worse by malnutrition and poor health conditions"

Sadly, war is responsible for a lot of things. The mixing of different population groups, poverty, malnutrition the colapse of the infrastructure that provides food and removes waste.
Any or all of these will contribute to fetal ill health.
A bunch of pictures of deformed babies is exactly the sort of image that indicates that the website will be crassly unbalanced, with no regard given to any other possible casue for the problem than the one they wish to rant about.
If we are going to talk about this on a science website please can we have some science.
Uranium isn't nice stuff, but it's a natural material- we have always had to put up with the stuff.
A five fold rise in cancer rates isn't a good thing but it is just as "reasonable" to blame the effect on the presence of Amrericans as on DU. ("the DU arrived and the cancer rate went up" is much the same as "the Americans arrived and the cancer rate went up")
Since conventional explosives are often rather toxic materials it might make more sense to blame them, but then you wouldn't know which side to rant at.
Title: What is Depleted Uranium?
Post by: NobodySavedMe on 15/06/2008 18:12:37
Is there any evidence that depleted uranium causes birth defects?
It is certainly true that they happen without depleted uranium- they happened before the stuff was ever made.
Is there a statistically significantly higher incidence in these areas. Is there some way to rule out any of a large number of other potential causese- maternal stress would be an obvious one but there are plenty of others.

Sthis is a threda about depleted uranium on a scientific site. Oughtn't the replies stick to well evinced data about the stuff rather than poltics?

Well, well, well.

Just as expected Borad Chemist bats for the Establishment at every chance.

He is a corporate foot soldier.

I wish i was there to offer him  some depleted uranium dust on his cereals.

This justifies what i said about him elsewhere.

This is what happens when a uncritical minds looking for certainty impels it to feast on shadows.
Title: What is Depleted Uranium?
Post by: Bored chemist on 15/06/2008 19:19:02
Well, well, well.

"Just as expected Borad Chemist bats for the Establishment at every chance."

Sometimes the establishment is right. On  the other hand I'm fairly militantly atheist. In my country the head of state is a religious figure. I clearly don't always bat for the establishment but MeSavedNobody hasn't noticed.


"He is a corporate foot soldier."
I don't work for a corporation, nor have I ever done so, nor have I ever represented one. Unfortunately, once again MSN doesn't spot this flaw in his rant.


"I wish i was there to offer him  some depleted uranium dust on his cereals."
It's a tiny change in the risk I face, but if you could replace the normal uranium in my diet by depleted uranium my net radiation exposure would fall.
Please do so if you get the chance.

"This justifies what i said about him elsewhere."
No comment.

"This is what happens when a uncritical minds looking for certainty impels it to feast on shadows."
Indeed, an uncritical mind finds biased rants about depleted utranium then parrots them on sites like this.
At least the DU debate is mainly a matter of being rude about the US and UK Govts (both of whom probably deserve it). In this  at least it's better than the reprehensible behaviour sugested by one of his other pet causes. If you look here
http://www.thenakedscientists.com/forum/index.php?topic=15081.0
you will see him expousing the virtue of a site which recommends that people with malaria stop taking drugs that are known to work and try diluted pool cleaner instead.

He's not getting the message about ad hom atacks either.
Title: What is Depleted Uranium?
Post by: NobodySavedMe on 17/06/2008 12:43:16
Well, well, well.

"Just as expected Borad Chemist bats for the Establishment at every chance."

Sometimes the establishment is right. On  the other hand I'm fairly militantly atheist. In my country the head of state is a religious figure. I clearly don't always bat for the establishment but MeSavedNobody hasn't noticed.


"He is a corporate foot soldier."
I don't work for a corporation, nor have I ever done so, nor have I ever represented one. Unfortunately, once again MSN doesn't spot this flaw in his rant.


"I wish i was there to offer him  some depleted uranium dust on his cereals."
It's a tiny change in the risk I face, but if you could replace the normal uranium in my diet by depleted uranium my net radiation exposure would fall.
Please do so if you get the chance.

"This justifies what i said about him elsewhere."
No comment.

"This is what happens when a uncritical minds looking for certainty impels it to feast on shadows."
Indeed, an uncritical mind finds biased rants about depleted utranium then parrots them on sites like this.
At least the DU debate is mainly a matter of being rude about the US and UK Govts (both of whom probably deserve it). In this  at least it's better than the reprehensible behaviour sugested by one of his other pet causes. If you look here
http://www.thenakedscientists.com/forum/index.php?topic=15081.0
you will see him expousing the virtue of a site which recommends that people with malaria stop taking drugs that are known to work and try diluted pool cleaner instead.

He's not getting the message about ad hom atacks either.

Heavy metals are toxic, is universally accepted.Except by you.

Thousands of RETURNIG soldiers and LOCAL natives have been injured by it.Yet like king canute you try to delude others.
Title: What is Depleted Uranium?
Post by: NobodySavedMe on 20/06/2008 22:25:57
"Whatever the effect of the DU shells, it is made worse by malnutrition and poor health conditions"

Sadly, war is responsible for a lot of things. The mixing of different population groups, poverty, malnutrition the colapse of the infrastructure that provides food and removes waste.
Any or all of these will contribute to fetal ill health.
A bunch of pictures of deformed babies is exactly the sort of image that indicates that the website will be crassly unbalanced, with no regard given to any other possible casue for the problem than the one they wish to rant about.
If we are going to talk about this on a science website please can we have some science.
Uranium isn't nice stuff, but it's a natural material- we have always had to put up with the stuff.
A five fold rise in cancer rates isn't a good thing but it is just as "reasonable" to blame the effect on the presence of Amrericans as on DU. ("the DU arrived and the cancer rate went up" is much the same as "the Americans arrived and the cancer rate went up")
Since conventional explosives are often rather toxic materials it might make more sense to blame them, but then you wouldn't know which side to rant at.

hey folks!...depleted uranium is natural stuff...don't forget to sprinkle it on your daily cereal.

deformed babies?..that just due to malnutrition..says bored chemist.
Title: What is Depleted Uranium?
Post by: Bored chemist on 21/06/2008 20:49:42
"hey folks!...depleted uranium is natural stuff...don't forget to sprinkle it on your daily cereal.

deformed babies?..that just due to malnutrition..says bored chemist."
Wrong on both counts. Try harder or give up.