IMPROVED OPTIMUM CONDITION FOR RECOVERY AND MEASUREMENT OF Polonium-210 IN ENVIRONMENTAL SAMPLES
An improved laboratory technique for measurement of polonium-210(210Po) in environmental samples has been developed in Radiochemistry and Environmental Laboratory (RAS), Malaysian Nuclear Agency. To further improve this technique, a study with the objectives to determine the optimum conditions for 210Po deposition and; evaluate the accuracy and precision results for the determination of 210Po in environmental samples was carried-out. Polonium-210 which is an alpha emitter obtained in acidic solution through total digestion and dissolution of samples has been efficiently plated onto one side of the silver disc in the spontaneous plating process for measurement of its alpha activity. The optimum conditions for deposition of 210Po were achieved using hydrochloric acid (HCl) media at acidity of 0.5 M with the presence of 1.0 gram hydroxyl ammonium chloride and the plating temperature at 90oC. The plating was carried out in 80 mL HCl solution (0.5 M) for 4 hours. The recorded recoveries obtained using 209Po tracers in the CRM IAEA-385 and environmental samples were 85% – 98% whereby the efficiency of the new technique is a distinct advantage over the existing techniques. Therefore, optimization of deposition parameters is a prime importance to achieve accuracy and precision results as well as economy and time saving.