Fungi Locks Depleted Uranium

In this new study, the researchers found that free-living and plant symbiotic (mycorrhizal) fungi can colonize depleted-uranium surfaces and transform the metal into uranyl phosphate minerals.

Fungi may have an important role to play in the fate of potentially dangerous depleted uranium left in the environment after recent war campaigns, according to a new report in the May 6th issue of Current Biology, a publication of Cell Press.

The researchers found evidence that fungi can “lock” depleted uranium into a mineral form that may be less likely to find its way into plants, animals, or the water supply. Because fungi are perfectly suited as biogeochemical agents, often dominate the biota in polluted soils, and play a major role in the establishment and survival of plants through their association with roots, fungal-based approaches should not be neglected in remediation attempts for metal-polluted soils.

The testing of depleted-uranium ammunition and its recent use in Iraq and the Balkans has led to contamination of the environment with the unstable metal. Depleted uranium differs from natural uranium in the balance of isotopes it contains. It is the byproduct of uranium enrichment for use in nuclear reactors or nuclear weapons and is valued for its very high density. Although less radioactive than natural uranium, depleted uranium is just as toxic and poses a threat to people.