搅拌棒吸附-热脱附-气相色谱质谱法(SBSE-TD-GCMS)分析环境空气中的多环芳烃(PAHs)

Analysis of polycyclic aromatic hydrocarbons(PAHs)in ambient air using stir bar sorptive extraction-thermal desorption coupled with gas chromatography-mass spectrometry

以聚二甲基硅氧烷(Polydimethylsiloxane,PDMS)为被动大气采样吸附剂,建立了搅拌棒吸附-热脱附-气相色谱质谱法(SBSE-TD-GCMS)分析环境空气中16种多环芳烃(PAHs)的方法.结果表明,16种PAHs的检出限(LOD)范围为0.06~3.00 pg,回收率为75%~136%,标准曲线线性关系良好(R^(2)>0.99),日内重复性和日间重复性的相对标准偏差(RSD)分别为<7.1%和<17%.茚并[1,2,3-c,d]芘、二苯并[a,h]蒽、苯并[g,h,i]苝的脱附残留为21%~24%,其余13种PAHs脱附残留<13%.用建立的方法分析了室外空气样品和从汽车上采集的空气样品中的PAHs.结果发现,室外空气样品中全部检出PAHs,采样时间为4 d的样品中16种PAHs含量为0.058~52.3 ng.11种PAHs的吸附量与采样时间线性相关.对于行驶的汽车中的样品,车窗外和排气管处的Σ_(16)PAHs(16种PAHs的和)含量分别为车内的2.5倍和2.1倍.

Stir bar sorptive extraction-thermal desorption-gas chromatography-mass spectrometry(SBSE-TD-GCMS)was applied to determinate 16 polycyclic aromatic hydrocarbons(PAHs)in ambient air using polydimethylsiloxane(PDMS)as the adsorbent for passive air sampling.The method provided limits of detection(LOD)ranging from 0.06 to 3.00 pg,recoveries in the range of 75%~136%and excellent linearities(R^(2)>0.99),and the intra-day and inter-day repeatability RSDs(relative standard deviation)were less than 7.1%and 17%respectively for 16 PAHs.Carry-overs for all the PAHs were<13%,with the exception of indeno[1,2,3-c,d]pyrene,dibenz[a,h]anthracene and benzo[g,h,i]perylene for which carry-overs were in the range of 21%~24%.The proposed method was used for the determination of PAHs in the outdoor air and air samples collected from the car.PAHs were detected in all the outdoor air samples,with the contents of 16 PAHs varying between 0.058 ng and 52.3 ng(sampling period of 4 days).Significant linear correlations were observed between sequestered amounts and sampling times for 11 PAHs.As for the samples from the car,the contents ofΣ_(16)PAHs(sum of 16 PAHs)in the samples collected from the window and exhaust pipe were 2.5 and 2.1 times higher than those from the cabin,respectively.