A collaborative study of a method for the determination of polycyclic aromatic hydrocarbons in fly ash from waste incineration

The aim of the study was the performance evaluation of a method for the determination of polycyclic aromatic hydrocarbons based on sample Soxhlet extraction, cleanup by thin-layer chromatography and gas chromatographic quantification. Analyses were carried out by eight laboratories on fortified fly ash samples. The findings showed that the method can provide substantially reliable results for 4- to 6-ring PAHs, with a molecular weight of up to 278. A high interlaboratory variability, however, was observed (mean CVs were 49% and 26%, respectively). It was supposed to arise mainly at the stage of gas chromatogram interpretation. Some analytical parameters related to this source of variability were also evaluated.