Abdallah Mohamed Abou-Elwafa, Ibarra Catalina, Neels Hugo, Harrad Stuart, Covaci Adrian
Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
J Chromatogr A. 2008 May 9;1190(1-2):333-41. doi: 10.1016/j.chroma.2008.03.006. Epub 2008 Mar 7.
Domestic and office dust samples (n=37) were analyzed for hexabromocyclododecanes (HBCDs) using gas chromatography-electron-capture negative ionization-mass spectrometry (GC-ECNI/MS) and liquid chromatography-electrospray tandem mass spectrometry (LC-ESI/MS/MS). To determine the best method to quantify HBCDs using GC-ECNI/MS, BDE 128 was used as internal standard (I.S.) in all samples, while 13C-labeled alpha-HBCD was used as I.S. in some samples. Total HBCD concentrations (sum of alpha-, beta-, and gamma-HBCD diastereomers) were calculated using response factors (RFs) for alpha- and gamma-HBCD as individual diastereomers and using an average RF for both diastereomers. Statistical comparison showed that concentrations obtained via GC-ECNI/MS were statistically indistinguishable (p>0.05) from those obtained using LC-ESI/MS/MS. The closest match between the two techniques was obtained using [13C]alpha-HBCD as I.S. and the average RF for alpha- and gamma-HBCDs. Excellent linear correlations (Pearson coefficient values r>0.9) were obtained between the GC-ECNI/MS and LC-ESI/MS/MS results, with slopes ranging from 0.76 to 1.36. Pentabromocyclododecenes (four isomers) and tetrabromocyclododecadienes (two isomers) were detected in the studied samples and were identified as degradation products of HBCDs after separation from the parent compound on the basis of both retention time and mass spectrum. This finding suggests that the elimination of HBr is the major degradation pathway for HBCDs in dust.
采用气相色谱 - 电子捕获负电离 - 质谱联用仪（GC - ECNI/MS）和液相色谱 - 电喷雾串联质谱仪（LC - ESI/MS/MS）对37份家庭和办公室灰尘样本中的六溴环十二烷（HBCDs）进行了分析。为确定使用GC - ECNI/MS定量HBCDs的最佳方法，所有样本均使用BDE 128作为内标（I.S.），而部分样本使用13C标记的α - HBCD作为内标。总HBCD浓度（α - 、β - 和γ - HBCD非对映异构体的总和）通过将α - 和γ - HBCD作为单个非对映异构体的响应因子（RFs）以及两种非对映异构体的平均RF来计算。统计比较表明，通过GC - ECNI/MS获得的浓度与使用LC - ESI/MS/MS获得的浓度在统计学上无显著差异（p>0.05）。使用[13C]α - HBCD作为内标以及α - 和γ - HBCDs的平均RF时，两种技术之间的匹配度最高。GC - ECNI/MS和LC - ESI/MS/MS结果之间获得了极好的线性相关性（Pearson系数值r>0.9），斜率范围为0.76至1.36。在所研究的样本中检测到了五溴环十二烯（四种异构体）和四溴环十二碳二烯（两种异构体），根据保留时间和质谱从母体化合物中分离后将其鉴定为HBCDs的降解产物。这一发现表明，HBr的消除是灰尘中HBCDs的主要降解途径。
