Evaluation of four mass spectrometric methods for the gas chromatographic analysis of polychlorinated n-alkanes

Abstract The suitability of four mass spectrometric methods for the gas chromatographic analysis of polychlorinated n -alkanes (PCAs, also called chlorinated paraffins) was evaluated and compared using spiked and fish liver samples. Electron ionization tandem mass spectrometry (EI–MS/MS) as well as electron capture negative ionization (ECNI) combined with low and high resolution mass spectrometry and CH 4 /CH 2 Cl 2 -negative ion chemical ionization (NICI) low resolution mass spectrometry were investigated. All methods showed an accuracy of 100% for the ECNI methods. EI–MS/MS and CH 4 /CH 2 Cl 2 -NICI led to errors of maximum 17% and 33%, respectively, independent from the degree of chlorination of the used reference standard.