NOT-SO-SECRET-WEAPON: A U.S. Air Force A/OA-10 Thunderbolt II from the 355th Fighter Squadron is surrounded by a cloud of gun smoke as it fires a 30-millimeter GAU-8 Avenger Gatling gun over the Pacific Alaska Range Complex in Alaska on May 29, 2007. The A-10's standard 30-millimeter rounds contain depleted uranium, although CENTCOM says DU rounds have not been used in Afghanistan. Image: DOD PHOTO BY AIRMAN 1ST CLASS JONATHAN SNYDER, U.S. AIR FORCE
President Obama has called for the withdrawal of 33,000 U.S. troops from Afghanistan over the next year and the remaining 68,000 by the end of 2014, but questions linger regarding what the troops are leaving behind after more than nine years of combat. In particular, Afghanistan President Hamid Karzai has accused U.S. and NATO-led coalition troops of littering his country with weapons that use "nuclear components."
Karzai made this comment last week during an address to the Afghanistan Youth International Conference, throughout which he broadly criticized coalition forces and pointed out that the U.S. has been in negotiations with the Taliban in an attempt to end the fighting set off by the September 11, 2001, terrorist attacks. U.S. Secretary of Defense Robert Gates, during an appearance June 19 on CNN's State of the Union news program, confirmed such negotiations had taken place. Less clear, however, are exactly which weapons Karzai was referencing and their long-term impact on the Afghani people and their country.
Karzai's comments likely refer to ammunition that uses depleted uranium (DU) to pierce armor or, conversely, to strengthen armored vehicles, according to scientists as well as intelligence and policy analysts. They also note that DU is not "nuclear" in the sense that brief exposure to it would not cause radiation sickness or cancer in the way that fallout from a nuclear warhead or meltdown would. DU, the main by-product of uranium enrichment, is a chemically and radiologically toxic heavy metal that is "mildly radioactive," with about 60 percent of the activity of natural uranium, according to the United Nations Environment Programme (UNEP).
"In short, DU munitions are not even remotely on the same scale of danger as having a war in the first place," says Jeffrey Lewis, director of the East Asia Nonproliferation Program at the James Martin Center for Nonproliferation Studies and publisher of the ArmsControlWonk blog, which addresses disarmament, arms control and nonproliferation.
U.S. Central Command (CENTCOM), a Unified Combatant Command unit of the U.S. armed forces whose territory includes the Middle East, claims that no DU weapons are currently being used in Afghanistan, although a spokesman acknowledges that "DU-type munitions were used in Iraq in anti-tank and anti-armor weapons." The U.S. military itself has reported on its use of Fairchild Republic A-10 Thunderbolt II jet fighter aircraft in Afghanistan. Whereas the A-10's standard 30-millimeter rounds normally contain DU, CENTCOM says that the A-10s in use in Afghanistan are not using DU munitions.
Why use DU?
"Wherever we send our A-10s, soon enough we hear reports of uranium contamination thanks to depleted uranium," says Chris Bronk, an information technology policy research fellow at Rice University's James A. Baker III Institute for Public Policy and a former U.S. State Department diplomat. Still, it is unclear how much DU ammunition has actually been used in Karzai's country (either by the U.S. or its NATO allies) and the long-term impact of DU on the environment, he adds.
DU kinetic-energy rounds are an effective way of penetrating armored vehicles. "You want something dense, and DU is denser than lead, something on the order of 1.6 times the density of lead," says Kristian Gustafson, deputy director of the Brunel Center for Intelligence and Security Studies (BCISS) at West London's Brunel University. "You've now upped your energy transfer by significant quantity." Still, U.S. and NATO air-strike targets in Afghanistan are more likely to be mud–brick buildings than armored vehicles, and DU rounds "are useless for anything other than smashing armor," he adds.
DU is used in anti-tank shells because it is a heavy metal that can slam through shielding plates on armored vehicles, agrees Hans Kristensen, director of the Federation of American Scientists' Nuclear Information Project.
How dangerous is DU?
The DU used in munitions is neither the same as natural uranium ore nor the radioactive uranium used in a nuclear reactor. DU is mostly composed of the isotope uranium 238 (U238); its more radioactive content, U235, is at least three times less than that of natural uranium, according to the World Health Organization (WHO). "Natural uranium ore contains almost entirely U238 but also a small amount of U235," Kristensen adds.