Burgy,
Some have already responded to some of your questions and comments. I was
away teaching today, so my comments are a bit late. I've interspersed my
comments after each of the points you mention below.
-----Original Message-----
From: John W Burgeson [mailto:burgytwo@juno.com]
Sent: Friday February 23, 2001 2:12 PM
To: asa@calvin.edu
Subject: DU (Depleted Uranium)
I was at a meeting yesterday where the subject was the US sanctions on
Iraq (the speaker, of course, was against them). Much of what he had to
say made a lot of sense; some did not.
In a leaflet he distributed and talked about was a description of what
was called "Depleted Uranium," (DU), which was also identified as the
isotope U-238. Included were all sorts of claims about it, claims which I
do not see as credible. But my physics career is too far remote now in
time for me to fairly judge these claims; perhaps someone here might
comment on them.
These are the claims, as extracted from somewhat more volitile phrases in
the leaflet:
1. The US used DU munitions in Iraq, Kuwait, Kosovo, Serbia, Bosnia,
Puerto Rico, Okinawa and within the US.
This is most likely correct as far as Iraq, Kuwait, Bosnia, Serbia, Kosovo
are concerned. Don't know about Okinawa, Puerto Rico or within US. Uranium
metal has a high specific gravity and will burn when heated to a high enough
temperature. Uranium metal fires are notoriously difficult to extinguish:
if you dump sand to burning U metal, the U will pull the O2 from the SiO2 in
the sand.
2. Thousands of individuals have been exposed (to what?) ...
Exposed to depleted uranium, probably in the form of U3O8. When the DU
bullets hit their target, they will burn their way through the armour and
produce U3O8 or UO2 or a mixture of these two (U forms a series of oxides
with O/U ratios of 2 to 2.33). This oxide is probably in the form of a fine
dust that could be inhaled or ingested.
3. DU is a health hazard if inhaled, ingested, or gets in wounds.
This will certainly be the case if it is inhaled, but how much of a health
hazard is difficult to say. Ingestion may be a problem if the particles are
very small and are (partially) dissolved by stomach acid.
4. Respiratory and skin protection must be worn by everyone within 80
feet of DU contaminated equipment.
Since we don't know all the health effects of DU, that's probably not a bad
idea.
5. DU contamination makes water & food unusable.
I doubt if DU contamination would make water unusable. The oxides also have
a high specific activity and would precipitate out. Uranium oxides are not
very soluble in water.
6. DU is made from the non-fissionable byproduct of the uranium
enrichment process.
True, natural uranium contains only 0.72% U-235, the fissionable isotope
used in nuclear reactors. Light water-moderated nuclear reactors (PWR and
BLW) need a higher concentration of U-235, so the U (as UF6) is put through
gaseous diffusion plants that yield uranium enriched in U-235 and "the rest"
i.e., uranium depleted in U-235, or U-238. The half life of U-238 is about
10 x that of U-235, so DU is less radioactive than natural uranium.
7. DU is used in munitions, shielding and commercial concrete.
Because of its high density, DU is used in shielding. It's also used in the
keels of high performance sailboats. Don't know why they would put it in
commercial concrete, though.
8. DU munitions are solid U-238 (several examples given).
Probably true, as DU munitions would be metallic DU.
9. Upon impact, radioactive and heavy metal poison U-238 fragments &
oxides are created.
True, as I have pointed out above. I would question the phrase "poison
U-238," though.
10. Reported health effects (official DOD document, not identified)
include (long list of diseases).
My understanding (I am not a physician) is that these links are tenuous.
11. Doing nothing wall leave "thousands of radioactive heavy metal poison
bullets" around.
True, but "so what?" These very tiny particles will be washed into the soil
by rain and will sink to the bottom of lakes and into the sediments.
The article is written by a Doug Rome, Ph.D., who is identified as a
former ODS (?) health physicist and a former Army DU Project director.
If U-238 is a stable isotope, as I always thought it was, then whence
comes the radioactivity? And while I'm fairly sure that ground up U-238
powder is probably not good to inhale, is it really a poison? That is, is
it worse than, for instance, an equal amount of West Texas dust?
U-238 is NOT stable. It has a very long half life but will decay by alpha
emission. I don't know enough about West Texas dust to compare its
toxicity. ;-) (and, no, don't send me any!)
The anti-sanctions movement seems to me to be a good one to support. But
these claims, which seem wild to me, don't give me any confidence in the
rest of their message.
There is a lot of confusion about DU. It certainly is less radioactive than
natural U and I doubt if the illnesses have anything to do with radiation.
Maybe uranium is chemically toxic (like arsenic or mercury or lead). There
is also no question that a lot of soldiers who have returned from the Gulf
War and from Bosnia that are suffering from strange diseases. One Canadian
soldier died recently and an autopsy reportedly showed elevated levels of
DU. This is strange, because we all have trace amounts of natural uranium
in our bodies so evidence of DU should be detectable by a lower than normal
U235/238 ratio.
Hope this sheds some light on the topic.
Chuck Vandergraaf
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