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SUMMARY
With the first use of the depleted uranium (DU) ammunition on the Gulf War battlefields in 1991, questions have been raised about the indiscriminate adverse health effects of these new weapons. Although depleted uranium is both radioactive and toxic, US Government sponsored research invariably comes to the conclusion that the adverse health effects are non-existent or negligible. The present review on the radioactivity, military use, and health effects of depleted uranium attempts to compare the depleted uranium contamination at the manufacturing facilities, ammunition proving grounds, and battlefields with the US regulatory standards.
Depleted uranium is a byproduct of uranium enrichment process, with a relatively small contribution from reprocessing of nuclear spent fuel. Based on the most accurate measured isotopic composition of depleted uranium, the total activity can be calculated as 22% less and a-activity as 43% less compared to natural uranium. The Department of Energy is in possession of almost 3/4 of a million metric tons (1.6 billion lb.) stockpile of depleted uranium hexafluoride for a total activity 527,000 Ci and a-activity 193,000 Ci. Civilian applications of depleted uranium include aircraft counterweights and g-radiation shielding. The overwhelming use of depleted uranium is for military applications, such as DU ammunition and tank armor. DU weapons are currently in the arsenal of all branches of the US military, including the US Army, US Air Force, US Navy, and the US Marine Corps. The largest US manufacturers of DU ammunition are the Starmet Corp. and the Alliat Techsystems. Many DU manufacturing facilities and DU ammunition proving grounds are severely contaminated by the past activities, although government sponsored research reports present the risks to humans as negligible. Some drastic remedial actions, such as removal of DU contaminated soil and shipping it to low-level radioactive waste dumps thousands of miles away, have barely scratched the surface of the problem.
DU ammunition was the most effective new weapon in the US military arsenal during the Gulf war against Iraqi armored targets. The amount of the expended DU ammunition reached 670,000 - 750,000 lb., 14% by the ground forces and the rest from aircraft, for the total released activity 320 - 360 Ci and a-activity 120 - 130 Ci. 20 - 70% of a DU round burns on impact and creates a cloud of radioactive and toxic aerosol dust contaminating air and soil within 50 m of the target (about 2 acres). Radioactive airborne emission created by just one DU tank round exceeds the US radiological limits for general public by 5 orders of magnitude and the residual surface contamination exceeds these limits by 3 orders of magnitude. When the contamination spreads with weather elements, almost 100 acres can become inaccessible to general public. The US army manuals direct the troops to handle the human causalities and destroyed targets as contaminated by radioactivity and toxic heavy metal. Since the US troop were not trained to protect themselves from DU contamination, about 400,000 Gulf War veterans have been potentially contaminated by depleted uranium dust from combet explosions and accidental fires. Calculations based on the known effects of DU ammunition show that in just 5 days of war, 20 minutes exposure to DU dust each day, the US troops could have accumulated enough uranium in kidney to reach the Nuclear Regulatory occupational limit for uranium's toxicity and exceed the Agency for Toxic Substances and Disease Registry minimal risk level for general public by an order of magnitude.
Handling unused DU ammunition poses little danger, because dose equivalent rates from b- and g-radiation of uranium daughter products are relatively low. Depleted uranium presents the greatest danger to human health when insoluble DU dust is inhaled or when soluble DU dust is inhaled or ingested. The short-term effect of uranium chemical toxicity is kidney damage, just like from other heavy metal ions. The long-term health effect of internal exposure to depleted uranium's a-radiation and chemical toxicity is cancer. Birth defects are also possible when a mother is exposed to uranium during pregnancy. Substantial increase in cancer rates (4´) has already been observed in the southern regions of Iraq, including a high proportion of childhood leukemias and lymphomas. Compared to the pre-war levels, excess birth defects have been observed in southern Iraq as well. Numerous US Gulf War veterans experienced debilitating symptoms since 1991, collectively known as the "Gulf War Syndrome". The Department of Defense and Veteran Administration maintained that no chemical weapons were used during the Gulf War, discounted the health effects of depleted uranium dust, and invariably diagnosed the sick veterans with Post Traumatic Stress Disorder or similar psychological problems. At the end of 1996, the House Committee on Government Reform and Oversight severely criticized both agencies for these policies. The committee found that exposure to multiple toxic substances, including depleted uranium, was a more likely cause of the veterans' illnesses.
When the battlefield effects of DU weapons are carefully compared to the US regulatory limits on depleted uranium exposure and contamination, the claim that these new weapons are conventional can no longer be maintained. They fit the definition of a radiological and chemical weapon. A complete test ban of DU weapons in the United States, lifting economic sanctions, and cooperation on the battlefield cleanup, both in Iraq and Yugoslavia, are included in our recommendations.
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