"After 130 days, only around five percent of the uranium dissolved in the water remained in the samples," says Newman-Portela. A Rare Form of Uranium AppearsThe next question was exactly what type of uranium compound had formed. A Uranium Compound That Remains StableThe researchers also determined that the pentavalent uranium combined with iron and oxygen to form FeU(V)O4. "It was found that even under the influence of atmospheric oxygen, this uranium compound had remained stable for more than 25 years. Potential for Uranium Cleanup"Our study has revealed for the first time that bacteria supplied with glycerol as a carbon source can convert toxic uranium dissolved in water into a stable chemical compound," says Krawczyk-Bärsch.