Three plutonium chelation cases at Los Alamos National Laboratory

Area of Science:

• Occupational Medicine
• Radiological Protection
• Toxicology

Background:

• Chelation therapy is crucial for internal contamination management.
• Diethylenetriaminepentaacetate (DTPA) is a primary decorporation agent for internally deposited radionuclides.
• Metallic plutonium (Pu) contamination poses significant health risks.

Observation:

• Three cases of metallic Pu-contaminated finger puncture wounds were treated with 1g Ca-DTPA or Zn-DTPA.
• One subject received a single injection, while two received multiple DTPA treatments.
• Detailed measurements of wound, urine, and excised tissues were analyzed for one case to assess chelation efficacy.

Findings:

• A four-orders-of-magnitude difference in Pu excretion was observed between peak values and levels at 100 days post-treatment.
• No significant difference in efficacy was found between Ca-DTPA and Zn-DTPA in this study.
• Chelation treatment 1.5 years post-incident showed an efficacy factor of approximately 50, albeit with a small averted dose.

Implications:

• DTPA chelation is effective in enhancing the elimination of internally deposited metallic plutonium.
• The timing of chelation may influence the overall reduction in committed dose.
• Further research can refine models for estimating plutonium intake and committed doses from excretion data.