Differentiating Polychlorinated Biphenyls (PCB’s) by GC / FID / ECD
The analytical chemistry of PCB’s is rigorous, demanding the highest quality in sample preparation and analytical technique. Insufficient sample extraction and inappropriate methods of sample clean-up are the most common sources of error in PCB analysis, which causes significant interference in the chromatography. However, even in relatively clean samples the problem remains to confidently distinguish PCB’s from other compounds in the sample. Since PCB’s are extremely complex mixtures of congeners, they are identified based on the presence and proportion of certain congeners (209 of which are catalogued in the Ballschmitter & Zell numbering system), and by the manufacturer trade name (i.e.; Aroclor, Kanechlor, etc.).