10 
BSH Report No. 56 
Limitations of GC-MS analysis for paraffin wax 
The workflow of oil spill Identification according to CEN2012 starts with a 
GC-FID analysis to characterise the mineral oil types or the mineral oil prod 
ucts. The decision to further proceed to GC-MS analysis Is based on the find 
ings of characteristic similarities between the Investigated samples. Character 
isation of blomarkers based on GC-MS analysis Is an essential part In oil spill 
Identification and In CEN2012. However, paraffin wax mostly Is a refined min 
eral oil product, which has undergone thermal and other physical processes. 
Therefore It Is not just a distilled fraction of the source oil but Is of a considera 
bly altered chemical composition. Therefore, blomarker analysis by GC-MS 
according to CEN2012 provides generally no reliable and meaningful possibil 
ity of discrimination between samples (Fig. 5). 
Hopanes 
(191m/z) 
alkyl. Phenan., Anthra. 
(192m/z) 
Triterpanes 
io (205m/z) 
alkyl. Dibenzothiop. 
(198m/z) 
lui-J' 
J 
C :: p 
- 
meth. Fluorant.,Pyr, 
(216m/z) 
Steranes 
(218m/z) 
L2 
arom. Steranes 
(231 m/z) 
1.2 
Steranes 
(217m/z) 
| 10 
i L 
. U 
mU: 
ju 
j nf 
1 ¡I LI , l.| 
0.6 
T, 
VjlwWkW 
L 
Fig. 5: Overview of biomarkers in paraffin wax. Presented are the corresponding ion-chromato- 
grams of important biomarkers, showing very low abundance. Only hopanes and steranes seem to 
be analysable. 
Therefore, It becomes clear that the elegant way of the oil Identification method 
according to CEN2012 which relies strongly on calculating ratios of the blo 
markers to form a highly Individual fingerprint of the oil Is of very limited use In 
case of paraffin wax. 
Thus, It Is obvious that there Is need for a different way to Identify similarities 
and differences of paraffin wax samples. 
As GC-MS might not be able to provide the necessary data the focus shifts to 
the question If the results of GC-FID analyses executed according to CEN2012 
can be used In an extended way for further paraffin Identification. 
Furthermore, the application of Isotope ratio mass spectrometry (IRMS) pro 
vides additional parameters for the Identification of paraffin wax.