PROFICIENCY TEST RESULTS FOR STRONTIUM-90 ANALYSIS IN ENVIRONMENTAL MATRIX AT RADIOCHEMISTRY AND ENVIRONMENT LABORATORY, MALAYSIAN NUCLEAR AGENCY

Abstract

Strontium-90 (Sr-90) is a radioactive isotope with significant health risks due to its long half-life and bone-seeking properties. Accurate analysis of Sr-90 is essential for environmental monitoring and safety assessments. This study presents the proficiency test (PT) results conducted at the Radiochemistry and Environment Laboratory, Malaysia Nuclear Agency, in 2021 until 2023. A total of nine samples, including spiked water, simulated contaminated surfaces, and seawater, were analyzed by using a gas proportional counter for beta counting. The acceptability of results was rated based on the trueness and precision determined by the relative bias and P values. Four results fell within the acceptable range, one was in the warning range, and four were deemed unacceptable. The main causes of the unacceptable results were due to the lack of Y-90 correction, loss of Sr-90 during sample preparation, and possible incomplete separation of Sr-90. These findings emphasize the need for method refinement, enhanced quality control, and continuous laboratory training to improve the accuracy and reliability of Sr-90 analysis.