Crude oils are fingerprinted by gas chromatography combined with mass spectrometry (GC/MS) according to the recommendations of the CEN Technical Report "Oil spill identification – Waterborne petroleum and petroleum products – Part 2: Analytical methodology and interpretation of results".
Analysis is performed by GC/MS following purification by low pressure liquid chromatography.
Quantitative analysis by CG/MS or GC/MS/MS (PAHs, VOCs, alkanes etc.)
Cedre has two gas chromatography-mass spectrometry systems (GC/MS or GC/MS/MS), equipped with multifunction sample changers.
Liquid injection can therefore be performed following sample extraction/purification, but water samples can also be directly analysed by Headspace (HS) analysis for volatile compounds or SBSE (Stir Bar Sorptive Extraction) for semi-volatile compounds.
Sediments or biological tissues can be extracted by ASE (Accelerated Solvent Extraction). These quantifications can also be performed within oils.
The methods applied routinely are:
- PAHs (43 molecules or groups of molecules) and linear alkanes (nC10 to nC38) in oil products, sediments and biological tissues (ASE).
- PAHs (21 molecules) in biological tissues (small samples) by alkaline digestion coupled with SBSE-GC/MS/MS analysis (Journal of Chromatography A, 2014).
- Volatile organic compounds (BTEX and other monoaromatic molecules and saturated compounds in the range C5-C10, list of 35 molecules) by HS-GC/MS in oil products and water.
- Dissolved organic compounds (PAHs, PCB and pesticides, around 65 molecules) by SBSE-GC/MS/MS.