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In response to the depleted uranium (DU) munitions usage in the Kosovo wars, the World Health Organization (WHO) published a report this April (2001), which includes guidelines on its impact on human health. The research states, "Young children could receive greater depleted uranium exposure when playing within a conflict zone because of hand-to-mouth activity that could result in high depleted uranium ingestion from contaminated soil (ENS, p.1)."
The average American, on the other hand, gets a minute dose equivalent to 0.03 rem from natural sources, and about 0.06 rem from man-made sources. Over a lifetime of 70 years, the cumulative average doses equals 21 rem from natural sources (Gulflink, p.7). 'Rem' refers to the traditional measurement of absorbed dosage or the energy left by radiation in a unit mass of irradiated material. However, in some developing countries and countries at war, exposure levels are much higher. This is because depleted uranium is often used in aircraft, missiles, heavy tank armor and anti-tank munitions.
DU is a dense by-product of the natural uranium enrichment process used in nuclear power. In addition to its usage in artillery, it is used as ballast in aircraft, radiation shields in medical equipment, radiation therapy and in containers for the transport of radioactive waste (ENS, p.1).
There are three possible ways a person can be exposed to DU - inhalation, ingestion and skin contact. Inhalation is the most likely for of exposure in conflicts similar to those in Kosovo. Ingestion additionally occurs in large sections of the population through contaminated drinking water or food, both of which are effected by soil contamination. It can also enter through the skin via open wounds or shrapnel.
Most uranium that enters the body is not absorbed and is eliminated through normal bodily functions. However, this is dependent on the kidneys' ability to filter and excrete the substance within 24 hours of exposure (WHO, p.2). In the case of a person whose kidneys have been debilitated by common infection, diabetes and auto-immune diseases, there is a risk of uranium poisoning. This can result in nausea and vomiting.
Once exposed to uranium, the solubility in the body varies according to the form of uranium. Soluble chemical forms are discarded from the lungs within days, while insoluble forms can take years. Uranium becomes chemically toxic when large amounts enter and are retained in the body, absorbed into the blood and carried to body tissues and organs. The severity of the toxicity is determined by how much is absorbed and distributed among the organs of the body. The uranium oxides concerned are UO3, UO2 and U308, which are relatively insoluble. They tend to dissolve slowly in bodily fluids (Gulflink, p.2). The kidneys, being the body's filter, are the most effected, and depending on the level of concentration toxicity, can be damaged and killed - decreasing their ability to filter impurities from the blood (Gulflink, p.2). Once absorbed into the blood, up to 90% of the dissolved uranium is excreted within the first few days. The remaining 10% deposit in the bones and other organs (Gulflink, p. 3).
Typical soil concentrations of uranium in America number a few parts per million (half-a-teaspoon to 8-cubic yards of soil). The Agency for Toxic Substances and Disease Registry (ATSDP) estimates that there are typically four tons of uranium in a sq. mile of soil one foot deep with an added 180 metric tons (198 US tons) of uranium decay products in US agricultural lands annually, due to the trace amounts of uranium in phosphate fertilizers (Gulflink, p.1).
However, DU concentrations in military zones are much higher. DU munitions were first used in the Gulf War but did not receive wide attention until the Balkans conflict of 1998 and 1999 (ENS, p.2). When the largely Albanian population of Kosovo was plunged into war for independence from the Serb dominated Yugoslav government, NATO fired 31,000 DU shells. This prompted a recent report by WHO entitled, "Depleted Uranium: Sources, Exposure and Health Effects."
In their report, WHO health care experts say it is not necessary to screen the general population in areas where DU munitions have been used (ENS, p.2 and WHO, p.5). However, in the same document, WHO acknowledges that DU has 60% of the radioactivity of natural uranium and "significant chemical toxicity" (ENS, p.2). Despite this fact, WHO's recommendation is merely that anyone who believes they have been exposed to it should see a medical practitioner (ENS, p.2). They also recommend that preventative measures be taken for the sake of the young (ENS, p.1) Ultimately, the only safe solution for the problem of depleted uranium exposure is a ban on usage in uncontrolled environments until thorough and adequate studies can ascertain the full effects - both short and long-term. In the meantime there is an unfortunate living laboratory in Kosovo...
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