Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films

Area of Science:

• Environmental Science
• Radiochemistry
• Analytical Chemistry

Background:

• Plutonium (Pu) poses risks in aquatic ecosystems due to its alpha emission and long half-life.
• Understanding Pu bioavailability and speciation is vital for assessing ecological and human health impacts.

Purpose of the Study:

• To introduce and validate the diffusive gradients in thin films (DGT) technique for in-situ measurement of Pu bioavailability and speciation.
• To investigate the environmental behavior and redox chemistry of Pu in aquatic systems.

Main Methods:

• Development of a specialized diffusion cell for laboratory experiments with Pu.
• Adjustment of plutonium oxidation states (Pu(IV) and Pu(V)) to simulate environmental conditions.
• Calibration of the DGT technique and application using accelerator-based mass spectrometry in a karst spring environment.

Main Results:

• Successful in-situ measurement of Pu bioavailability in a mineral freshwater environment using DGT.
• Demonstrated the capability of DGT to simulate environmental Pu behavior in model solutions.
• Established a specific DGT device for freshwater Pu monitoring.

Conclusions:

• The DGT technique provides a reliable method for in-situ Pu bioavailability and speciation assessment in aquatic ecosystems.
• This approach significantly enhances the understanding of plutonium's environmental behavior and biological transfer.
• The developed protocol offers a valuable tool for environmental monitoring and risk assessment related to plutonium contamination.