An independent comparison between supercritical fluid extraction (SFE) and Soxhlet extraction methods was conducted as part of a certification of PCB congeners in industrial soil. The study was performed in the framework of the PCB group for the Measurements and Testing Program (former BCR) under the Commission of the European Union. It involved 21 selected and independent laboratories experienced in congener-specific PCB analysis. The comparison was performed using both interlaboratory and intralaboratoiy data. SFE was performed independently by three laboratories, and the obtained data showed that SFE is a very competitive alternative in terms of both accuracy and precision. The soil was certified for eight PCB congeners ranging from 7.0 to 137 //g/g with interlaboratory RSDs of 9-13% using all but two (out of 34) individual results from the SFE group.In recent years, supercritical fluid extraction (SFE) has gained increased interest because of the potential for reducing (1) the use of large amounts of hazardous organic solvents and (2) the work connected with conventional methods.1-8 Unfortunately, but also understandably, early SFE methods were developed using spiked or fortified samples on a variety of homemade instruments.9-11 The results obtained indicated that SFE had a very