Depleted uranium

This chapter describes depleted uranium (DU) and its applications in weapons of mass destruction. It also highlights the DU exposure pathways, pharmacokinetics, health effects, toxicity, and available treatments. The major use of DU is by the military as an alloy in armor and ammunition. These applications take advantage of the unique metallic properties of DU, specifically the density and pyrophoric properties. Uranium is the heaviest naturally occurring element and is extremely dense. Uranium has a density 1.7 times the density of lead, and rods made of uranium are resistant to deformation. Uranium shielding is therefore used in the armor of military armored vehicles, allowing the deflection of enemy projectiles. The chemical toxicity of DU is only an issue if the metal is internalized. The three traditional pathways of exposure are inhalation, ingestion, and dermal contact. Typically, in nonmilitary situations, the main routes of natural uranium uptake are by inhalation and ingestion. Because of the use of DU in ammunitions and armor by the military, the more important routes of exposure are inhalation and internalization of the DU. DU can cause oxidative DNA damage by catalyzing hydrogen peroxide and ascorbate reactions, resulting in single strand breaks in plasmid DNA in vitro. The treatments for uranium exposure are limited. Chelation therapy is used to prevent acute toxicity of high doses of uranium in the systemic circulation, typically resulting from some sort of ingestion.