PAHs are aromatic compounds with condensed ring systems created by incomplete combustion processes or the pyrolysis of organic materials (wood, coal, fuel, oil, tobacco and waste) or foods (grilling, frying, roasting, smoking, drying). PAHs are of natural (volcanic activities or forest fires) or of anthropogenic (mainly motor vehicles and industrial processes, but also cigarette smoke) origin in the environment.
The Department for Contamination Analysis (KONA; formerly Competence Centre Cluster Chemistry) of AGES, which is part of the Institute for Food Safety in Linz, has been responsible for carrying out the tasks of a National Reference Laboratory for PAHs since 2006. KONA was nominated as the Bulgarian NRL for PAHs in 2014, in addition to its role as an Austrian NRL.
The KONA Department of AGES GmbH uses accredited special analysis processes to determine PAHs in foods, animal feed, soil etc. The following table represents the basic procedures within its PAH testing processes.
|Matrix ||Processing/Extraction||Clean Up||Separation process ||Detection|
|plant materials, etc.||Saponification using methanolic potassium hydroxide; extraction with cyclohexane||SPE (2x)||HPLC||FL/PDA|
|Soil, compost, sewage sludge, grains, etc..||Extraction using dichloromethane||SPE (2x)||HPLC||FL/PDA|
|Oils, fats||GPC (Cyclohexane/ethyl acetate)||HPLC||FL/PDA|
|food (general)||Saponification using methanolic potassium hydroxide; extraction using cyclohexane||SPE (2x)||HPLC||FL/PDA|
|Diverse foods||ASE (Aceton/Hexane) and GPC (cyclohexane/ethyl acetate)||HPLC||FL|
GPC = Gel permeation chromatography
SPE = Solid phase extraction
HPLC = High-performance liquid chromatography
FL/PDA: Fluorescence detector or photodiode array
ASE = Accelerated solvent extraction
The EU Joint Research Centre runs the EU-RL “European Union Reference Laboratory for PAH” on the site of the “Institute for Reference Materials and Measurements” (IRMM) in Geel/Belgium. The National Reference Laboratories of the individual Member States support this Community Reference Laboratory in its tasks and prove their high levels of competence in proficiency tests and workshops held by the EU-RL on a regular basis.