Detection Of The Fission Product Palladium-107 In A Pond Sediment Sample From Chernobyl

Radiometric or mass spectrometric analysis of the long-lived fission product Pd-107 is notoriously difficult. We developed and optimized a chemical separation protocol for minute amounts of radiopalladium with a subsequent measurement by inductively coupled plasma triple quadrupole mass spectrometry with propane as the collision gas. This allows for detection limits of <2 ng of Pd-107/kg, which makes the method suitable for environmental samples with low levels of Pd-107. For testing of this method, a sample of sediment from the Chernobyl cooling pond was analyzed. Indeed, it could be shown that the cooling pond sediment exhibits a uniquely increased Pd-107/Pd-105 ratio (0.08 +/- 0.02), thus strongly indicating detectable levels of Pd-107 using this method.