Determination of organochlorinated compounds and petroleum hydrocarbons insediment sample IAEA-408. Results from a world-wide intercalibration exercise

A sediment sample from the intertidal mudflats of the Tagus estuary was pre pared, homogenised and distributed globally to laboratories as the IAEA-408 intercomparison material for the analyses of organochlorinated pesticides, PCBs and petroleum hydrocarbons (PHs). A total of 48 laboratories from 36 countries reported their results. The data from participants show that ther e still remain some difficulties with the accurate determination of organic contaminants such as pesticides and polycyclic aromatic hydrocarbons (PAHs ). More consistent interlaboratory results were obtained for PCBs congeners . The final results of this intercomparison exercise enable individual part icipants to assess their performance and, where necessary, to introduce app ropriate modifications in their analytical procedures. Furthermore, as a se ries of statistical criteria was fulfilled for a number of compounds, the s ample IAEA-408 can now be used as a reference material for quality control in the determination of some persistant organic pollutants (POPs) in marine sediment samples.