Interlaboratory proficiency testing for measurement of the polycyclic aromatic hydrocarbon metabolite 1-hydroxypyrene in fish bile for marine environmental monitoring

The determination of PAH metabolites in fish bile is performed to assess the PAH contamination in fish for environmental monitoring. A growing number of laboratories in Europe use this parameter for national monitoring. However, an international intercomparison between laboratories has not taken place in the last years. Therefore the determination of the PAH metabolite 1-hydroxypyrene was tested in a collaborative trial performed by 10 laboratories from eight countries. Five samples of naturally contaminated fish bile covering different concentration levels were distributed among the participants. The present study was open for different methods: GS/MS, HPLC-fluorescence (HPLC-F), fixed wavelength fluorescence (FWF), and synchronous fluorescence spectrometry (SFS), respectively. The results suggest that all four methods under investigation are suitable for screening purposes, but only three methods have produced comparable results which could be used for a common monitoring database: GC/MS, HPLC-F, and SFS (with conversion factor). Most z-scores were within the acceptance criteria of ±2. The comparability of GC/MS, HPLC-F, and SFS results should be further improved because SFS is a widely used method with a great potential for monitoring. The present study contributes to the quality assurance of results for European marine monitoring.