Soil Ecosystem Responses to Depleted Uranium Contamination

Abstract

Military operations of the past two decades have used depleted uranium missiles and equipment, which have contaminated the soils of war‐torn areas. Once in the soil, the metal corrodes to oxidized forms whose solubility depends on soil conditions. This paper reviews the literature on the effects of depleted uranium contamination on bacteria, fungi, and plants to synthesize the research. This will enable soil microbiologists to understand the impact of uranium contamination on the ecosystem as a whole. Some bacteria thrive in high‐uranium environments, but many do not, so uranium contamination selects for the bacteria that can survive. Fungi can often tolerate it quite well, to the extent that some grow on depleted uranium chips and encourage faster corrosion. Some plants can accumulate uranium, but most can only tolerate it if the pH of the soil is high enough to keep the uranium insoluble and not bioavailable. Remediation techniques include natural attenuation, ex situ processing, and bioremediation, but none of these are perfect and the correct approach depends on the site. The negative human health effects associated with uranium contamination make further research and remediation work vitally important.