同位素模拟-气相色谱-串联质谱法测定邻苯二甲酸二(2-乙基)己酯在茶汤中的浸出率

Determination of Transfer Rates of Di-(2-ethylhexyl) phthalate during Tea Brewing by Gas ChromatographyTandem Mass Spectrometry with Isotope Simulation Technique

在排查茶叶冲泡和样品前处理过程中邻苯二甲酸二（2-乙基）己酯（di-（2-ethylhexyl）phthalate,DEHP）背景污染基础上,采用同位素模拟-气相色谱-串联质谱法研究茶汤中DEHP的浸出率。结果表明,有机试剂、实验器皿以及旋转蒸发浓缩过程会产生DEHP污染,背景污染造成DEHP在茶汤中的浸出率偏高,为13%～400%。同位素DEHP-D4模拟冲泡实验结果表明,DEHP-D4在茶汤中的浸出率为4.5%～11.9%,浸出率与茶叶中DEHP-D4质量浓度相关性较小,但与茶叶种类、冲泡方式和冲泡次数相关。该研究结果为茶叶中DEHP风险评估提供技术支撑,为制定茶叶中DEHP最大残留限量标准提供基础数据。

The secondary contaminant of di-（2-ethylhexyl） phthalate（DEHP） during tea infusion and sample preparation was investigated and controlled in this study.The aim of this research was to evaluate the transfer rate of DEHP during tea infusion using isotope DEHP-D_4 simulation and gas chromatography-tandem mass spectrometry（GC-MS/MS）.Serious secondary contaminant of DEHP could occur in the reagents and vessels used and the process of rotary evaporation,amounting to 13%–400%.Transfer rate of DEHP-D_4 was found in the range of 4.5%–11.9%,which was related with tea category,brewing method and number of brewing cycles,but not with the concentration of DEHP-D_4 spiked in tea.This finding is helpful for the risk assessment of DEHP and the formulation of maximum residue limit of DEHP in tea.