Determination of 210Pb and 210Po in Environmental Samples by Alpha Ray Spectrometry Using an Extraction Chromatographic Resin

A determination method using an extraction chromatographic resin (EiChroM Sr.Spec™) has been developed for 210Pb and 210Po in environmental samples by alpha ray spectrometry. 210Pb and 210Po were coprecipitated simultaneously on CuS at pH 4.0–5.5. These nuclides were then adsorbed on a Sr.Spec™ resin column (0.79×4.0 cm) in 4 M HCl. The 210Pb and 210Po on the resin were eluted with 8 M HCl and 6 M HNO3, respectively. 210Po was determined by alpha-ray spectrometry after plating on a stainless-steel disk. 210Pb was determined as 210Po produced from 210Pb decay. The method was applied to soil (IAEA-326) and sediments (NIST-4354, IAEA-135, IAEA-368) standard reference materials, and the results agreed with their recommended values. The chemical yield of Po ranged from 56 to 99% and the yield of Pb was 95%. The detection limits of 210Pb and 210Po were dy0.6 mBq/sample at a counting time of 70000 s.