Depleted Uranium as a Weapon of War

Brief submitted by Dr. Rosalie Bertell

August 1999

I am an epidemiologist, with 30 years of experience in studying the health effect of exposure to ionizing radiation. I would like to call the attention of the UN Human Rights Tribunal to the use of depleted uranium (DU) weapons against Iraq in the Gulf War, and by NATO in Bosnia and the Kosovo-Yugoslavian war. DU is radioactive waste, and it attains special deadly properties when it is fired in battle. Because of its density and the speed of the missile or bullet (up to 5 mach) containing it, DU bursts into flame on impact. It reaches very high temperatures, and becomes a ceramic aerosol which can be dispersed 100 km from the point of impact.

Because the radiation dose to the person depends on the strength of the source of radiation, and the time duration of the exposure, this ceramic aerosol formation is important. Ceramic (glass) is highly insoluble in the normal lung fluid, and when inhaled, this ceramic particulate will remain for a long time in the lungs and body tissue before being excreted in urine. The Rand report which was commissioned by the US government in response to criticisms of the use of DU in weapons, failed to note this nasty form of insoluble DU which distinguishes it from the uranium dust in the mining or milling experience. This property means the uranium and its decay products will remain inside the body longer, thereby increasing the local alpha particle radiation dose to tissue.

Much of the ceramic DU aerosol is in respirable size particles, 10 micrometer and less in diameter. It stays in the upper respiratory tract and lungs for upwards of two years. The uranium oxide which was discussed in the Rand report had a one year half life in lungs. Most natural uranium contamination in the human body comes via food, and to a lesser extent from drinking water, not via the lungs.

Ingested uranium is excreted in feces, basically never entering into the human blood and lymph system. In contrast, the DU ceramic aerosol released in war entered directly into lymph and blood through the lung-blood barrier and circulated throughout the whole body. All internal contamination is excrete through either sweat or urine.

DU is a very powerful alpha particle emitter, with each particle carrying a force of about 4.2 MeV (million electron volts). It requires only 6 to 10 eV (electron volts) to break the DNA or other large molecules in the body. This long stay of DU from weapons within the body, can now be demonstrated through 24 hour urine analysis. The presence of DU eight years after the Gulf War exposure, means that the internal organs: lung, lymph glands, bone marrow, liver, kidney, and immune system have experienced significant localized radiation damage. Testing of urine for both veterans of the Gulf War and citizens of Iraq has confirmed this long term exposure to DU.

Women (because of their radiation sensitive breast and uterine tissue) and children (because their bones are growing, thus able to pick up more DU than adults, and they have a long expected life-span in which the cancers with long latency periods can develop) will be most at risk from the delayed DU weapon action. DU in the environment is very much like land mines.

The Military Toxics Project (MTP), asked me, in the Fall of 1997, to take initiative in investigating the effect of DU on the Gulf War veterans. I tried several clinical approaches in order to determine, if possible, the extent of this problem. Among the most successful approaches was that of 24 hour urine analysis. Dr. Hari Sharma, a nuclear chemist at the University of Waterloo in Canada, was at first asked to determine the presence or absence of DU in the urine of the veterans. He took a sample from the veteran's total 24 hour urine output, 50 to 200 ml, and calculated the amount of U238 and U235. He gave results as the amount of each isotope per litre of urine rather than per 24 hour sample, since the fact of contamination was at the time more important than the amount of contamination. The amount can still be ascertained from the original data, and will be included in a final report.

Since no DU occurs naturally, all uranium found in urine should be natural uranium unless there is a specific exposure to depleted or enriched uranium. From the two isotopic measurements, one can tell whether or not DU is present in the total sample of uranium by the following method:

Samples: Micrograms Micrograms Ratio

U 235 U238 U235/U238

Natural U 0.72 99.28 0.0073

Enriched U 4.00 96.00 0.0417

Depleted U 0.20 99.80 0.0020

Pure U238 0.00 100.00 0.0000

Allowing for some variation in measurement, any observed ratio below 0.0073 is a considered to be a mixture containing depleted uranium.

This first approximation indicated that DU was present in the urine of both the Gulf War veterans and some of the Iraqi people, in quantities ranging from 0 to 10 micrograms, averaging 2 micrograms per litre for Iraqi citizens and 3 micrograms per litre for GW veterans. The radiation dose evaluation based on the biological half life for insoluble uranium oxide of 500 days, suggested by ICRP, shows that there is significant radiological hazard from this DU inhalation. DU is also a heavy metal, and is chemically toxic to humans. The true (observed) biological half life of this ceramic uranium, appears likely to be more than 10 years, and this presents an even more enhanced chemical and radiological hazard. For example, the magnitude of the individual hazard for fatal cancer may be as high as 3% to 5% for some veterans.

Dr. Sharma also undertook an analysis of some veteran's second urine sample, taken one year after their first sample was analyzed, in order to get some idea of the rate at which the DU was being excreted from the body in urine. Knowing this rate of excretion, one can mathematically reconstruct the amount likely to have been present in the body in 1991. This would be helpful in determining the total radiation dose which the person would receive from this exposure over the 50 years following that exposure. It is this quantity which would be needed to estimate total detriment to the individual due to the exposure.

Such excretion rate estimates also will enable Dr. Sharma to approximate the observed biological half-life of the specific ceramic uranium mixture inhaled in the Gulf War. All of these theoretical results require tedious calculations, and they are not yet ready for general distribution. However, they will be important for any future claims of any veterans or civilians. Since the nature of the exposure was common to all participants or spectators in the Gulf War, all will be able to use these results both for medical and legal purposes.

Radiation dose to the individual depends on the length of time the DU was in the body. Knowing these common theoretical parameters makes the individual measurements more meaningful. Simply measuring the amount of DU in one urine sample does not allow one to estimate the dose which the person has from all of the DU still in body tissues, or which will be received from the original exposure. It is these complex measurements which require time, and which we note, the main users of DU, have failed to provide to the medical community.

More accurate laboratory techniques have now been used by Dr. Sharma, with some financial help from others and some of his own money, and the uranium isotopic measurements are now accurate to 0.1%. With this accuracy, it will in the future be possible to estimate quite accurately the proportion of the uranium excreted in urine which is DU, and the quantity of DU excreted per 24 hour period. Together with the other theoretical parameters, this quantity can then be converted into an estimate of the original exposure in 1991, and the integrated radiation dose expected. Any estimate of health effects requires this dose estimation.

The more general conclusion, namely that the internal DU contamination of veterans, still evident eight years after their exposure in the Gulf War, is quite firm now.

Details of the methodology and findings will be organized for publication by Dr. Sharma by the end of this year. The process of publication in a peer review journal might take another year. It might be possible after that to undertake individual measurements in a well organized program for the veterans. However, this will require outside funding. It should be possible to demand that the Governments in various countries where DU exposure occurred, provide this service to their people. It should also be possible to train other laboratories to undertake these measurements.

The Precautionary Principle should dictate an even faster response: an immediate stoppage of the use of DU and care for the detoxification of veterans and civilians suspected of having had exposure. Methods of detoxification need also to be developed and tested for efficacy.

I would refer the reader to a paper on DU which I wrote in preparation for the Hague Peace Conference in May 1999. It is important that the soil in Iraq, Bosnia, Kosovo and Yugoslavia be tested for DU. Like land mines, DU will continue to affect people long after the war is over. The aerosol can be resuspended in wind or when disturbed by traffic and inhaled by people. Ecological studies on the long term behaviour of DU in the environment need to be undertaken. Some of the shrapnel left from the war may also be radioactive and it needs to be removed by competent radiation protection personnel.

Two points need to be stressed: veterans and civilians in these wars WERE exposed to DU; and this inhaled DU represents a seriously enhanced risk of damaged immune systems and fatal cancers. This type of radiological and chemical warfare should be banned.

(Published on the internet by Matthias Reichl 29.01.2002)

siehe auch Radioactive contamination of Yugoslavia by NATO-bombing and -shelling