COMPARISON OF GC-ECD, GC-MS AND GC-AED FOR THE DETERMINATION OF POLYCHLORINATED-BIPHENYLS IN HIGHLY CONTAMINATED MARINE-SEDIMENTS

Electron capture detection (ECD), low- and high-resolution mass spectr ometry (LR- and HRMS), and atomic emission detection (AED) were compar ed for the gas chromatographic (GC) detection of polychlorinated biphe nyls (PCBs) present in highly contaminated marine sediments. With ECD, LRMS, and even HRMS, detection was seriously disturbed by the complex matrix of the sediments, whereas AED in the chlorine-selective mode p rovided excellent PCB profiles without interferences. In addition, GC- AED provided congener independent responses, which enabled accurate qu antitation of ail PCBs based on a single calibration curve. However, b ecause GC-AED was less sensitive than the other techniques studied, pr eparation of relatively large amounts of sample (10-20 g dry sediment) was required for mast analyses.