High-Throughput Analysis of ²³⁸Pu in Urine by ICP-MS/MS

As a highly toxic α radionuclide, plutonium-238 can enter the human body through inhalation, ingestion and other pathways and remain for a long time in nuclear industry and radioactive workplaces, posing potential risks to the ecological environment and occupational health. The traditional alpha spectrometry has a long analysis cycle, which is difficult to meet the timeliness requirements of environmental emergency monitoring and batch screening. In this study, a high-throughput analysis method for ²³⁸Pu in urine based on ICP-MS/MS was established, with the chemical separation and purification process optimized as the key part. The performances of TEVA and TK200 extraction chromatography resins were compared systematically, and the elution conditions were optimized via orthogonal experiments. Elution with 20 mL of 0.1 mol/L HCl–0.05 mol/L hydroxylamine hydrochloride achieved a chemical recovery of 98.74% for ²³⁸Pu and a decontamination factor of 1.55×10⁵ for ²³⁸U, which significantly eliminated mass spectral interference. The method detection limit was 0.38 Bq/L, applicable for the routine monitoring of occupational personnel and rapid screening in environmental emergencies, and it provides technical support for the assessment of internal exposure dose and early warning of ecological risks.