Fast GC of PCBs

Keywords Fast GC PCB dl-PCBs WHO-PCBs sewage sludge HT-8 separation power carborane 

Due to the widespread use of PCBs as dielectric and heat-transferring fluids in power transformers, hydraulic fluids, intense use as plasticizers and flame retardants and due to their stable molecular structure, PCBs with its 209 possible congeners, are still today subject to be monitored in environmental analysis (US EPA, 

In particular, the coplanar dioxin like dl-PCBs, or non-ortho-substituted PCBs, are of increasing analytical importance because of their toxicity similar to 2,3,7,8-TCDD (tetrachlorodibenzodioxin) with a significant contribution to the sample TEQ value. 

The 12 so-called dl-PCBs or WHO-PCBs of toxicologic importance are the coplanar non-ortho substituted congeners of a total number of 68 coplanar congeners of which 20 in total are non-ortho substituted  

The GC separation of these PCB congeners has been based for a long time on low and intermediate-polarity phases, such as 5% phenylsilicone (typically DB-5MS, TR-5MS, etc.). Problems with co-elution, poor detection at low levels and the need for better separation of the highly toxic coplanar PCBs demand columns with increased selectivity. 

---