基于串联SPE净化和GC-HRMS技术测定母乳中溴代二噁英/呋喃

Determination of polybrominated dibenzo-p-dioxin/furans in human milk using tandem SPE purification and GC-HRMS

[背景]溴代二噁英/呋喃(PBDD/Fs)主要来源于溴代阻燃剂的排放。随着近几十年来溴代阻燃剂的大量使用,环境中的溴代二噁英/呋喃的含量逐渐增高。[目的]建立快速、准确测定母乳中13种溴代二噁英/呋喃的气相-高分辨质谱(GC-HRMS)检测方法。[方法]将母乳冷冻干燥后,经加速溶剂萃取仪提取,分散固相萃取除脂,串联固相萃取净化和气相-高分辨质谱检测,同位素稀释法定量。[结果]本方法的检出限为0.002~0.012 pg/g(以50 g样品计);具有良好的线性范围,决定系数(R2)>0.99;准确度和精密度实验结果显示,低浓度和高浓度的加标回收率分别为71.8%~101.8%、80.5%~97.8%,相对标准偏差(RSD)< 10%。基于本方法,测定了40份上海地区的母乳样品,PBDDs没有检出,PBDFs有2,3,7,8-四溴代二苯并呋喃(2,3,7,8-TetraBDF)、1,2,3,4,6,7,8-七溴代二苯并呋喃(1,2,3,4,6,7,8-HpBDF)和八溴代二苯并呋喃(OBDF)共3种化合物检出,检出率分别是72.5%、100%和67.5%。[结论]所建方法用于测定母乳样本中PBDD/Fs,结果表明该方法快速、准确、高效、可靠,为开展PBDD/Fs暴露风险评估和毒理学研究提供了方法学支持。

[Background] The emissions of brominated flame retardants have been proved to be the major source of polybrominated dibenzo-p-dioxin/furans (PBDD/Fs). With the extensive use of brominated flame retardants in recent decades, the concentrations of PBDD/Fs in the environment increase gradually.[Objective] This study aims to establish a rapid and accurate method for the determination of 13 PBDD/F congeners in human milk by gas chromatography-high resolution mass spectrometry (GC-HRMS).[Methods] Lyophilized human milk was subject to accelerated solvent extraction, dispersive solid phase extraction (SPE) defatting, and tandem SPE purification successively, and consequently detected by GC-HRMS with isotopic dilution method.[Results] This method showed low limits of detection (LOD, 0.002-0.012 ng/g, in 50 g milk sample), good linearity (correlation coefficients, R2 > 0.99), satisfactory accuracy (the recovery rates of lowconcentration spiked standard were 71.8%-101.8%, and the recovery rates of high-concentration spiked standard were 80.5%-97.8%), and high precision (relative standard deviations, RSD < 10%). Forty breast milk samples collected in Shanghai were determined by the method. PBDDs were not detected, and three PBDF congeners including 2, 3, 7, 8-tetrabromodibenzofuran (2, 3, 7, 8-TetraBDF), 1, 2, 3, 4, 6, 7, 8-heptabromodibenzofuran (1, 2, 3, 4, 6, 7, 8-HpBDF), and octabromodibenzofuran (OBDF) were positive, with detection rates of 72.5%, 100%, and 67.5%, respectively.[Conclusion] This method has exhibited rapidness, accuracy, efficiency, and reliability for the determination of PBDD/Fs in human milk samples. It provides methodological support for PBDD/Fs exposure risk assessment and toxicological research.