Applications of gas chromatography—mass spectrometry in monitoring environmentally important compounds

The use of gas chromatography-mass spectrometry (GC-MS) with electron impact (EI) and positive and negative chemical ionization (PCI and NCI, respectively) is a valuable confirmatory technique for unequivocal identification of pesticide residues and polychlorinated biphenyls in different environmental matrices. This article outlines some of the most important developments and makes recommendations for selecting the mode of GC-MS operation. Emphasis is placed on less commonly used techniques such as NCI, which provides high selectivity and sensitivity for specific groups of pollutants. The coverage is restricted and represents the personal perspective of the author.