title: Comparison and analysis of organochlorine pesticides and hexabromobiphenyls in environmental samples by gas chromatography-electron capture detector and gas chromatography-mass spectrometry.
abstract: Two analytical methods, gas chromatography-electron capture detector (GC-ECD) and gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS), were evaluated and compared for the measurement of persistent organic pollutants, specifically for 26 organochlorine pesticides and two hexabromobiphenyls, in atmospheric particulate matter and soil samples. The hypothesis tested was that the coelution of non-target compounds may lead to false positives when analyzed by GC-ECD, and that the overestimation associated with these false positives can be eliminated using GC-NCI-MS. The study showed that both methods had satisfactory linearity and reproducibility for the target compounds. Although the sensitivities of GC-ECD for most of the compounds investigated were higher than those observed with the GC-NCI-MS method, the matrices interference was obvious with GC-ECD. There was indeed an apparently high false-positive rate or overestimate when GC-ECD was used for environmental samples, implying that the GC-ECD method has been used with care and that GC-NCI-MS is generally superior for the analysis of trace amounts of these compounds in environmental samples. Based on these results, the sample extraction and cleanup procedures of the GC-NCI-MS method were optimized for achieving acceptable recoveries and less matrices interference.
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China fxiaof@pku.edu.cn.
authors.forename: Xiaofang
authors.initials: X
authors.lastname: Fu
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Shu
authors.initials: S
authors.lastname: Tao
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Liu
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China.
authors.forename: Bingjun
authors.initials: B
authors.lastname: Meng
mesh_terms: D000393:Air Pollutants / Q000032:analysis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis* / Q000737:chemistry; D016014:Linear Models; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D011075:Polybrominated Biphenyls / Q000032:analysis* / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry
chemical_list: D000393:Air Pollutants; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D011075:Polybrominated Biphenyls; D012989:Soil Pollutants