COMPARISON OF A RADIATION COUNTING METHOD AND ICP-MS FOR THE DETERMINATION OF TC-99 IN ENVIRONMENTAL-SAMPLES

Results of Tc-99 measurements between radiation and non-radiation coun ting methods were compared using four radiation sources for which Tc-9 9 has been previously determined with a gas-flow proportional counter or a GM counter. Each Tc-99 source consisted of a stainless steel plan chet bound by mylar films. Seaweeds collected from the Irish Sea were analyzed and 99Tc was electroplated on the planchet. The Tc-99 in each sample was separated and measured again by inductively coupled plasma mass spectrometry (ICP-MS). Tc was continuously removed from each sam ple with 2M HNO3 and 2M NaOH. After the solution containing Tc was adj usted to 0.1 M HNO3. Tc was extracted on a novel extraction chromatogr aphic resin to separate it from Ru. The total recoveries for Te on the planchet samples were almost the same with an average of 91%. The res ults of Tc-99 measurements by both radiation and non-radiation countin g methods agreed well with each other.