33 
Oil Spill identification - Round Robin 20045 
3.3 Obvious differences in the mass-chromatograms 
In order to be able to exclude possible source samples, which are 
obviously different, mass-chromatograms should be carefully checked 
visually before peak ratios are produced. 
This saves time and resources and improves the clarity of a report. 
51 2eichne4inlaro 
£50.39 
S50.2 
Wasserprobe zw.Ror -»• | 
j Brentstd Paul 
S50 20 RR PK1W2 
3085 
3192 
RR PK2W2 
RR PK3W2 
RR PK4W2 
AF, Egypt,Sidi Kenr(= 
AF, Egypt, S idi Kenr,(= j 
AF. Egypt.Sidi Kerifi* 
CIS, Tengiz,(=S141_! 
S50.39 
S50.2 
550.20 
550.21 
Wasserprobe zw.Ror 
Brentstd Paul 
RR PK1W2 
RR PK2W2 
| S50.22 
RR PK3W2 
550.37 
550.38 
550.39 
S.50.2 
S50.20 
AF, Egypt,Sidi Kerir(= 
AF, Egypt,Sidi Kerir,(= 
AF. Egypt.Sidi Kerir,(= 
CIS, Tengiz,(=S141_; 
AF Amnia f— r "‘ “ - ^ 
ME, lran(=S141_202 
S trand,Sylt,Klappholt" 
Wasserprobe zw Ròr 
Brentstd Paul 
RR PK1W2 
S50.21 RR PK2W2 
RR PK3W2 
RR PK4W2 
AF. Egypt.Sidi Kerir(= 
AF. Egypt.Sidi Kerir,(= 
AF Fr,,.r.* Ciri; 
jirard..S; r it.K.ldpph:ilt. i~[’' 
Wasserprobe zw.Ror 
Brentstd Paul 
RR PK1W2 
RR PK2W2 
RR PK3W2 
S50.23 RR PK4V/2 
AF, EgyphSidi Kerir(= 
AF. Egypt.Sidi Kerir.(= || 
AF, Egypt,Sidi Kerir,(= ^ i 
Fig 10: 
Mass 216 (bsh) 0 5 v j 0US difference in the relation of benzo(a)fluorene (B(a)F to 4- 
methylpyrene (mass 216, see Fig 11 for identification) compared to all 
other samples could have been found in source II (lower right). This 
difference cannot be caused by weathering, because B(a)F is reduced in 
the source sample and not in the spill sample, as would have been 
when caused by weathering. 
Expressed in numbers, this difference reaches 40 to 46% (repeatability, 
both, BSH and RIZA results). Further differences of 18 to 20% are 
found in masses 192 (M-phenantrenes) and 234 (retene-methylated 
naphthalenes).