TY - JOUR A1 - van de Kreeke, Johannes A1 - de la Calle, B. A1 - Held, A. A1 - Bercaru, O. A1 - Ricci, M. A1 - Shegunova, P. A1 - Taylor, P. T1 - IMEP-23: The eight EU-WFD priority PAHs in water in the presence of humic acid JF - Trends in analytical chemistry N2 - Recently, the International Measurement Evaluation Programme (IMEP) organized an interlaboratory comparison on total concentrations of eight polycyclic aromatic hydrocarbons (PAHs) in natural inland waters. It was carried out in support to the European Union Water Framework Directive (EU-WFD) that lists these eight as priority substances. As sample matrix, we used groundwater spiked with humic acid as a model for the colloidal substances that are present in natural inland waters. Humic substances can adsorb PAHs, but we found that some laboratories did not apply analytical procedures that sufficiently accounted for this. One of these laboratories was involved in establishing the reference values. We show how this impacted on the reliability of their measurements. Many participants accepted our invitation to report their measurement uncertainties. We assessed their results against our reference values and uncertainties, and provided z and zeta scores. Although the overall measurement capability appears satisfactory, there is room for improvement of analytical procedures as regards the use of measurement standards. KW - Dissolved organic matter (DOM) KW - Humic substance KW - Interlaboratory comparison (ILC) KW - Internal standard KW - International measurement evaluation programme (IMEP) KW - Polycyclic aromatic hydrocarbon (PAH) KW - Reference value KW - Uncertainty KW - Water KW - Water framework directive (WFD) PY - 2010 DO - https://doi.org/10.1016/j.trac.2010.04.009 SN - 0165-9936 SN - 0703-7147 VL - 29 IS - 8 SP - 928 EP - 937 PB - Elsevier CY - Amsterdam AN - OPUS4-21865 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -