Detection Capability of 89Sr and 90Sr Using Liquid Scintillation Counting.

Area of Science:

• Environmental Chemistry
• Radiochemistry
• Analytical Chemistry

Background:

• Accurate determination of Strontium-89 (89Sr) and Strontium-90 (90Sr) is vital for environmental monitoring and public health.
• Existing methods may face challenges with sensitivity and interference, particularly in complex matrices like water samples.

Purpose of the Study:

• To develop and validate a novel method for the simultaneous determination of 89Sr and 90Sr.
• To emphasize enhanced detectability and address potential interferences for improved accuracy.
• To assess the method's performance against regulatory requirements for drinking water and food monitoring.

Main Methods:

• Simultaneous quantification of 89Sr and 90Sr using liquid scintillation counting in three spectral windows.
• Chemical purification of strontium followed by gamma spectrometry for chemical recovery assessment (using 85Sr tracer).
• Numerical analysis of data by solving linear equations, incorporating 90Y activity and propagating uncertainties.

Main Results:

• The method demonstrated high accuracy with average biases of -0.3% for 90Sr and -1.5% for 89Sr.
• En-scores were within acceptable limits (-1.0 to 1.0 at 95% confidence), indicating good agreement.
• Detection capabilities (LC, MDA) were calculated, considering all uncertainties and compared to regulatory standards; a new approach for interference was developed.

Conclusions:

• The developed method provides a reliable and sensitive approach for simultaneous 89Sr and 90Sr determination in water.
• The method effectively addresses radionuclide interference, improving the accuracy of measurements.
• This technique is suitable for regulatory monitoring, including compliance with Safe Drinking Water Act requirements.