VALIDATION OF A RADIOCHEMICAL SEPARATION AND ALPHA SPECTROMETRIC METHOD FOR DETERMINATION OF ²³⁴U, ²³⁵U, AND ²³⁸U IN ENVIRONMENTAL SAMPLES

Abstract

This study presents the validation of a radiochemical separation and alpha spectrometric method for the determination of uranium isotopes (²³⁴U, ²³⁵U, and ²³⁸U) in environmental samples. The procedure was evaluated using two International Atomic Energy Agency (IAEA) certified reference materials (CRMs), namely IAEA-385 (Irish Sea Sediment) and IAEA-384 (Fangataufa Sediment), to assess its analytical performance. Validation parameters included selectivity, accuracy, precision, repeatability, ruggedness, and robustness. The calculated u-scores and z-scores were within acceptable limits, and relative bias values demonstrated good agreement with certified values. Inter-analyst comparison using IAEA-385 confirmed the method’s ruggedness, while consistent performance across different CRMs demonstrated its robustness. The validated procedure provides a reliable and standardized approach for uranium isotope analysis in environmental matrices and is established at the Radiochemistry and Environment Laboratory, Malaysian Nuclear Agency, for routine environmental monitoring applications.