Lead isotope measurement using a multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS)

Lead (Pb) as a trace element occurs in rocks and has four stable isotopes (Pb-204, Pb-206, Pb-207, Pb-208). Pb is released into the atmosphere, biosphere, hydrosphere and geosphere through various industrial activities, such as smelter, mining, combustion of fossil fuels and use of leaded gasoline, and result in serious environmental contamination. Pb isotopes can be used to trace the Pb contamination source and to understand of the biogeochemical cycling of Pb in the environment. Pb purification with two-step chemical separation using hydrochloric acid (HCl) and hydrogen bromide (HBr) can yield high precise and accurate results although it needs a lot of time and labor during Pb purification. Here, we developed one-step chemical separation using only HCl. In order to develop an efficient separation method, two kinds of ion exchange resins, Eichrom Sr-resin and Pb-resin, were used to compare the separation and recovery of Pb from other matrix elements. Further, in order to verify this method we measured Pb isotopes in several geological reference materials distributed by USGS and NRCC. The results are consistent with the reported values within the error, indicating that this method is successfully developed. It is expected that this study can be broadly used to measure Pb isotopes in various environmental samples.