Detection of the Fission Product Palladium-107 in a Pond Sediment Sample from Chernobyl

Abstract

Radiometric or mass spectrometric analysis of the long-lived fission product 107Pd 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 107Pd/kg, which makes the method suitable for environmental samples with low levels of 107Pd. 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 107Pd/105Pd ratio (0.08 ± 0.02), thus strongly indicating detectable levels of 107Pd using this method.

Atomic spectrometry update – a review of advances in environmental analysis

“…A high-yielding (82-97% recoveries) column-based chromatographic procedure was used 26 to isolate Hf, Nd and Sr from NIST SRM 1633b (coal y ash), 1648a (urban particulate matter) and IRMM CRM BCR 723 (vehicular road dust) for isotopic analysis by MC-ICP-MS. Provisional Hf 176 /Hf 177 , Nd 143 /Nd 144 and Sr 87 /Sr 86 data were reported. Similarly, the NIST SRM 1648a (urban particulate matter) and NIST SRM 1649a (urban dust) were analysed 27 by MC-TIMS and MC-ICP-MS to determine the Am, Np, Pu and U contents and isotopic ratios.…”

“…The corresponding errors for Th ranged from −16% for IAEA-326 (soil from Kursk region, Russia) to −7% for IAEA-447 (soil from Hungary). Determination of 107 Pd at low levels (<2 ng kg −1 ) was achieved 144 through a multistep separation process involving Pd retention on a Ni resin and determination with ICP-MS/MS. The method was applied to sediment from the cooling pond at Chernobyl.…”