Radiochemical determination of technetium-99

Area of Science:

• Environmental Science
• Radiochemistry
• Analytical Chemistry

Background:

• Technetium-99 (99Tc) is a long-lived radionuclide with environmental significance.
• Accurate quantification of 99Tc in biological matrices like vegetation is crucial for environmental monitoring and risk assessment.

Purpose of the Study:

• To develop and validate a robust analytical procedure for determining 99Tc concentrations in vegetation samples.
• To establish a reliable method for environmental monitoring of 99Tc contamination.

Main Methods:

• Wet-ashing of vegetation samples to prevent 99Tc loss.
• Separation of 99Tc from other radionuclides via calcium carbonate precipitation.
• Purification of 99Tc using anion-exchange chromatography and electro-deposition.
• Quantification using Technetium-95m (95mTc) as an internal tracer and Ge(Li) gamma-ray spectrometry.
• Beta-particle counting with a scintillation counter for 99Tc activity determination.

Main Results:

• The developed procedure minimizes 99Tc loss during sample preparation.
• Effective separation and purification of 99Tc were achieved.
• The method demonstrated a detection limit of 0.1 pCi for 99Tc in approximately 10 g of vegetation with a 3000-min count.

Conclusions:

• The validated procedure provides accurate and reliable determination of 99Tc in vegetation.
• This method is suitable for routine environmental monitoring and assessment of 99Tc levels.