A rapid and reliable method for Pb isotopic analysis of peat and lichens by laser ablation-quadrupole-inductively coupled plasma-mass spectrometry for biomonitoring and sample screening

作者：Kylander M E^*; Weiss D J; Jeffries T E; Kober B; Dolgopolova A; Garcia Sanchez R; Coles B J

来源：Analytica Chimica Acta, 2007, 582(1): 116-124.

DOI：10.1016/j.aca.2006.08.050

• laser ablation
• Pb isotope
• environmental monitoring
• multi-collector
• biological sample
• peat
• lichen

An analytical protocol for rapid and reliable laser ablation-quadrupole (LA-Q)- and multi-collector (MC-) inductively coupled plasma-mass spectrometry (ICP-MS) analysis of Pb isotope ratios (Pb-207/Ph-216 and (211)pb/Pb-216) in peats and lichens is developed. This technique is applicable to source tracing atmospheric Pb deposition in biomonitoring studies and sample screening. Reference materials and environmental samples were dry ashed and pressed into pellets for introduction by laser ablation. No binder was used to reduce contamination. LA-MC-ICP-MS internal and external precisions were < 1.1% and < 0.3%, respectively, on both Pb-207/Pb-206 and Pb-208/Pb-206 ratios. LA-Q-ICP-MS internal precisions on Pb-207/Pb-206 and Pb-208/Pb-206 ratios were lower with values for the different sample sets < 14.3 % while external precisions were < 2.9%. The level of external precision acquired in this study is high enough to distinguish between most modem Pb sources. LA-MC-ICP-MS measurements differed from thermal ionisation mass spectrometry (TIMS) values by 1% or less while the accuracy obtained using LA-Q-ICP-MS compared to solution MC-ICP-MS was 3.1% or better using a run bracketing (RB) mass bias correction method. Sample heterogeneity and detector switching when measuring Pb-208 by Q-ICP-MS are identified as sources of reduced analytical performance.

• 出版日期2007-1-16