Influence of Extracellular Polymeric Substances on Plutonium Sorption to Bacteria

摘要

Decades of nuclear weapons testing and production have left a legacy of radionuclide contamination at many sites around the world. One of the most pressing concerns is the eventual fate of the radionuclides released into the environment. Plutonium (Pu) is of particular concern as over 2000 metric tons have been deposited in the subsurface worldwide. Its long half-life (~(239)Pu - 2.4 ×10~4 yr) coupled with high toxicity makes it of particular concern for long-term risk assessments. Complications in predicting environmental behavior of Pu arise from its ability to exist in different oxidation states (Ⅲ, Ⅳ, Ⅴ, and Ⅵ) and the resulting differences in geochemical behavior. Additional complexities in Pu behavior occur in the presence of microbes and microbial exudates.