[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Some more authoritative info on DU in Kosovo
A-10s fire 20mm DU rounds.
______________________________ Reply Separator _________________________________
Subject: Some more authoritative info on DU in Kosovo
Author: radsafe@romulus.ehs.uiuc.edu at smtplink
Date: 1/10/01 5:31 PM
Dr. Jaworowski is the retired Head of the Central Lab, member and former
chairman of
UNSCEAR, and author of the famous article in Physics Today that
indicts/convicts the rad protectionists from misrepresenting science to claim
the possibility that the LNT can be true.
Regards, Jim
jmuckerheide@cnts.wpi.edu
Center for Nuclear Technology and Society at WPI
Radiation, Science, and Health
================================================
(Zbigniew, Was I right in putting a "n" in Domanski? :-)
Dear Jim,
A hot question now in Europe is depleted uranium in Kosowo. I prepared a
text on this subject for the Polish government. You might be interested in
this.
Best wishes,
Zbigniew
_____________
Zbigniew Jaworowski
Central Laboratory for Radiological Protection
ul. Konwaliowa 7, 03-194 Warszawa, Poland
voice: (48-22)717-6250; fax: 717-5324; e-mail: jaworo@clor.waw.pl
-------------------------------------
MEDICAL EFFECTS OF DEPLETED URANIUM IN KOSOVO
Zbigniew Jaworowski
Central Laboratory for Radiological Protection, Warsaw, Poland
Between March and June 1999 about 3000 to 30 000 35 mm - caliber rounds,
fitted with depleted-uranium, were fired over Kosovo and to a lesser extent
over Serbia, mainly by American A-10 assault aircraft. The core of each round
contained about 0.80 kg of almost pure uranium-238, from which its 14
radioactive daughters and uranium-235 were separated. This depleted uranium is
much less radioactive than natural uranium normally present in the soil and
rock, where it has since time immemorial been in equilibrium with radioactive
isotopes of radium, radon, thorium, protoactine, polonium, lead and bismuth.
During its decay it emits energetic alpha particles (4.26 MeV) and very weak
beta (0.01 MeV) and gamma (0.001 MeV) radiation. However, its immediate short
lived daughters emit a more energetic beta (2.29 MeV) and gamma (1.00 MeV)
radiation. Alpha particles penetrate to a rather short distance in the air and
in human tissues.
The total mass of depleted uranium dispersed over Kosovo ranged between 2.5
and 25 tons. The radioactivity of one round was about 10 megabecquerels (MBq).
Assuming that 30 000 rounds were fired, one can easily calculate that a total
activity of about 300 000 MBq of uranium-238 activity was dispersed over the
environment of Kosovo. In a 1 cm thick layer of soil in Kosovo (area: 10 887
km2) the radioactivity of natural uranium-238 in equilibrium with its
daughters amounts to about 100 000 000 MBq. Thus, a 1-cm thick layer of soil
in Kosovo contains about 300 times more natural uranium than that dispersed
there by American forces. However, at the target sites, the local
concentrations of depleted uranium may be higher than the average
concentration of natural uranium in the soil. From these patches of activity
depleted uranium may be resuspended into the air, and also enter the food
chain. This, however, should not lead to any observable medical consequences.
The weak beta and gamma radiation does not pose any serious radiation
protection problems. For example, radiotoxicity of inhaled uranium-238 (in
terms of Sv per Bq) is over 1000 times lower than radiotoxicity of cesium-137.
Because of these features of depleted uranium, its radiation protection
standards are based not on its radioactivity but on its chemical toxicity.
Like other heavy metals (lead, cadmium, or mercury) uranium is a toxic agent.
Experimental and epidemiological studies, carried out over half a century,
suggest that the main adverse effect of uranium-238 is chemical impairment of
the renal function. Secondary protection standards for uranium-238 (for
example concentration limits in air and food) are based on a limit of 3
micrograms of uranium per gram of kidney.
In epidemiological studies of over 32 000 workers, exposed to uranium between
1943 and 1986 in nuclear installations in the USA and UK, except for renal
problems, no other health impairment was observed, which could be related to
this metal. Among this worker cohort mortality due to all diseases was lower
than in the general population, and mortality due to all cancers and leukemia
was also lower.
Among about 150 000 soldiers, who for various periods of time were stationed
in Kosowo between March 1999 and the end of 2000, up to now 17 died due to
leukemia. This corresponds to about 11 deaths per 100 000 soldiers. The annual
leukemia death rate in the United Kingdom is 11 per 100 000. Thus, the rate of
soldiers dying due to leukemia appears to agree with European norms.
Some years ago "clusters" of leukemia were found in several countries, in
which the morbidity of leukemia was higher (up to ten times) than that in the
general population. The first of such clusters was discovered in the village
of Seascale, near Sellafield, which is the site of the main nuclear fuel
reprocessing plant in the United Kingdom. The excess was reported in a
television program in November 1983, and later similar clusters were found in
other places in the UK and later in Germany, France, Canada and the USA. At
first it was suspected that the cause of clusters are radioactive emissions
from nuclear installations. However, it was soon realized that they also
appear at other non-nuclear sites where migration of large number of people
occurred. In an extensive review of these findings in its 1994 report UNSCEAR
concluded that a possible explanation is that these excesses are due to a
spread of infection resulting from the mixing of populations from urban and
rural areas. One might expect that this phenomenon could also occur among
large military formations. But this may not be the case in Kosovo, where the
incidence of leukemia fits the European norm rather well. The shortest latency
time for leukemia induced by ionizing radiation is two years. As this disease
began to appear among the soldiers much earlier, and since no reports on a
dramatic increase of renal problems were filed, the cause of leukemia in
Kosovo, does not seem to be radiation from depleted uranium, but rather a
natural one. This is supported also by the fact that no increase in diseases
of kidneys, which are a critical organ for uranium, occurred among the
soldiers in Kosovo.
Professor T. Domanski from Poland before few years served as a head of a study
group of the Ministry of Health of Kuwait responsible for estimation of health
effects depleted-uranium munition in this desert country. He recently reported
that according to estimate of this group about 100 000 rounds with depleted
uranium were fired over Kuwait during the Gulf War, what corresponds to about
300 tons of uranium dispersed in the environment. Unexploded munition,
splinters and military equipment destroyed with uranium munition are stored at
depots in the desert. Uranium contamination of the ground, up to a level 10 to
20 times higher than average natural level, was found only to a distance of up
to 100 meters from the depots, and no contamination of local vegetation was
observed. Professor Domanski reported that until 1998 no increase of leukemia
and other cancers was observed in Kuwait, that might be related to depleted
uranium.
So, is this just much ado about nothing, or is it merely an expression of a
negative feeling towards a new type of ammunition or towards Americans?
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html
************************************************************************
The RADSAFE Frequently Asked Questions list, archives and subscription
information can be accessed at http://www.ehs.uiuc.edu/~rad/radsafe.html