烟叶中Pb同位素比值的ICP-MS测定及地域差异比较

Determination of Lead Isotope Ratios of Tobacco by ICP-MS and Their Areal Difference

摘要: 采用HNO₃-H₂O₂体系微波消解、电感耦合等离子体质谱和标样-样品交叉法测定了国内10省100个地区100个B1F烟叶样品中的Pb同位素比值。结果表明:①²⁰⁷Pb/²⁰⁶Pb和²⁰⁸Pb/²⁰⁶Pb比值的短期测量稳定性的相对标准偏差分别为0.08%和0.09%,样品测量的最佳浓度范围是10~50μg/L;②同一省区烟叶样品的²⁰⁷Pb/²⁰⁶Pb和²⁰⁸Pb/²⁰⁶Pb分布相对集中,不同省区烟叶样品的²⁰⁷Pb/²⁰⁶Pb和²⁰⁸Pb/²⁰⁶Pb则差别明显。烟叶样品的²⁰⁷Pb/²⁰⁶Pb和²⁰⁸Pb/²⁰⁶Pb可用来比较其地域性差异。

Abstract: The lead isotope ratios of 100 B1F tobacco samples from 100 areas of 10 provinces in China were determined by ICP-MS combining with HNO₃-H₂O₂ microwave digestion and standard-sample-bracketing method.The results showed that the relative standard deviations of ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb for short-term measurements were 0.08% and 0.09%,respectively.The optimal concentration range of sample was from10 to 50 μg/L.The difference of lead isotope ratios between samples from the same province was relatively narrower,while that between samples from different provinces was obviously wider.The isotope ratios,²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb,of tobacco sample could be used for comparing areal difference.