Depleted Uranium: Toxicology and Health Consequences

Depleted uranium (DU) is a dense heavy metal and an alpha particle emitter used in military and industrial applications. Exposure can occur via wounding, ingestion or inhalation. Several recent studies have investigated the potential health effects of this unique heavy metal. These in vitro and in vivo investigations have not only demonstrated the neoplastic transforming ability, the mutagenicity and the genotoxicity of DU, but also the neurotoxicity of DU. Studies using neoplastically transformed human cells and the athymic nude mouse assay demonstrated the carcinogenic potential of DU. DU exposure has been shown to induce genomic instability in a human cell model and alpha-particle radiation is responsible for some of the cellular damage induced by DU. Chronic long-term internal exposure to embedded DU could be a carcinogenic risk and comparisons to other types of uranium exposure, i.e., occupational inhalation of natural uranium, are problematic. Chronic internal exposure studies in vivo have demonstrated that DU is leukemogenic and neurotoxic. Epidemiological studies are inconclusive and the use of depleted uranium in armor-penetrating munitions remains a source of controversy because of the numerous unanswered questions about its long-term health effects. Keywords: Depleted uranium; internal contamination; alpha-particle radiation; heavy metal; toxicology; carcinogenesis; leukemia