Comparison of Standard Liquid Extraction and Direct Thermal Desorption GC/MS Techniques for the Analysis of Charcoal Filters used for Indoor Air Purification in a PCB Contaminated Building


App Note 2/1996

Many buildings constructed from prefabricated elements are widely contaminated with PCB originated in e.g. elastic sealants which act as permanent sources for several years. Indoor air filtration is part of a restoration strategy for these buildings using activated carbon filter media [1]. The analysis of PCBs trapped on these filters is usually carried out using standard liquid extraction followed by GC/MS analysis of the extract. This standard technique will be compared to direct thermal desorption of the filter material in combination with cryo-focusing in the liner of a cooled injection system, followed by temperature programmed sample transfer to the analytical column. It will be shown that direct thermal desorption is a reliable and fast method for the determination of PCBs in air charcoal filters without requiring any sample pretreatment.