沉积物中16种多环芳烃单体碳同位素GC-C-IRMS测定

为监测海洋沉积物中的多环芳烃（PAHs）、追踪污染物来源并控制污染，建立了沉积物中16种多环芳烃单体碳同位素GC-C-IRMS测定方法。首先采用EA-IRMS联用技术对16种多环芳烃单体碳同位素进行了定值，偏差范围在0.03‰~0.15‰（n=10），小于0.2‰；再用该16种多环芳烃混标，运用GC-C-IRMS联用技术考察了高效薄层色谱、气相色谱进样体积、无分流时间、进样浓度等可能产生的同位素分馏，结果表明，整个方法并无明显的同位素分馏现象。根据不同浓度PAHs混标在GC-C-IRMS测定中的变化与EA-IRMS测定的差，建立了数据校正曲线，其R2大于0.99，并应用于沉积物中16种多环芳烃单体碳同位素的测定，测试数据为海域沉积物中多环芳烃溯源提供了有力证据。 

Compound-specific carbon stable isotope analysis of 16 polycyclic aromatic hydrocarbons in sediments by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS)

A method for the compound-specific carbon stable isotope analysis of 16 polycyclic aromatic hydrocarbons (PAHs) in ocean sediments by Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS) was established for monitoring PAHs, tracing pollutant sources and controlling pollution. The compound-specific carbon stable isotope of 16 PAHs was determined by Elementary Analyzer-Isotope Ratio Mass Spectrometry (EA-IRMS) with a peak area deviation of 0.03‰-0.15‰ (n=10) (<0.2‰). The isotope fractionation of the 16 PAHs caused by High Performance Thin Layer Chromatography (HPTLC), injection volume of GC, purge time or sampling concentration was investigated using GC-C-IRMS and PAH-MIX. The results indicated that there was no apparent isotope fractionation during the whole process of analysis. Some calibration curves were obtained according to the changes of GC-C-IRMS data corresponding to the concentrations of PAH-MIX and the differences between GC-C-IRMS and EA-IRMS data, and the R2 value was higher than 0.99. The curves were used to determine the compound-specific carbon stable isotope of 16 PAHs in sediments, which offers strong evidence for tracing the source of PAHs in ocean sediments.