同位素稀释高分辨气相色谱-高分辨质谱法测定土壤样品中二恶英类化合物的等价毒性当量不确定度的评定

采用同位素稀释高分辨气相色谱-高分辨质谱法（isotope dilution high resolution gas chromatography and high resolution mass spectrometry，ID-HRGC-HRMS）测定土壤样品中二恶英类化合物（polychlorinated dibenzo-p-dioxins and dibenzofurans，PCDD/Fs）的等价毒性当量（toxic equivalent quantity，TEQ）。讨论并确定了测定土壤样品中二恶英类化合物2，3，7，8位异构体不确定度的来源并合成了各异构体的相对标准不确定度；在此基础上，计算了3种等价毒性当量因子（toxic equivalent factor，TEF）框架下土壤样品中PCDD/Fs的TEQ浓度及其合成不确定度和扩展不确定度。

Uncertainty evaluation of the determination of toxic equivalent quantity of polychlorinated dibenzo-p-dioxins and dibenzofurans in soil by isotope dilution high resolution gas chromatography and high resolution mass spectrometry

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in soil samples were analyzed by isotope dilution method with high resolution gas chromatography and high resolution mass spectrometry (ID-HRGC/HRMS), and the toxic equivalent quantity (TEQ) were calculated. The impacts of major source of measurement uncertainty are discussed, and the combined relative standard uncertainties were calculated for each 2,3,7,8 substituted congener. Furthermore, the concentration, combined uncertainty and expanded uncertainty for TEQ of PCDD/Fs in a soil sample in I-TEF, WHO-1998-TEF and WHO-2005-TEF schemes are provided as an example. I-TEF, WHO-1998-TEF and WHO-2005-TEF are the evaluation schemes of toxic equivalent factor (TEF), and are all currently used to describe 2,3,7,8 substituted relative potencies.