28 
Oil Spill identification - Round Robin 20045 
spill samples and two source samples and the question would be asked, 
"which samples match". 
3.2 GC-screening 
Nine of the twelve participants have started with GC-FID to screen the 
samples. In oil spill identification a fast GC-FID analysis is often used as 
a quick method to analyze all samples and to see which type of oil is 
involved and whether some of the samples can be eliminated from the 
final comparison by means of GC-MS. Additionally the method can be 
used to adjust the injection concentration for the GC-MS analysis. 
Differences in the fuel oil part between source I and source II could 
have been found already by GC-screening: 
1 
s 
1 
i 
1 
110 
100 
90 
SO 
70 
60 
50 
40 
30 
20 
10 
0 
overlay 
S50.23 
1 
i 
F 
- 
i 
- 
i i 
- 
- 
" 
j 
- 
1 I 
- 
t 
. 
j 
4 
J.mß* 
- 
li 
~L 
j 
i 
i 
-J 
Jki ” 
LjiP 
m 
l .il 
FIT 
m 
JKfl 
Im 
Ul 
^ 
2 3 4 5 6 7 8 9 10 11 12 
Zeit [min] 
Fig. 3 : Gas-chromatograms of samples source I and source II (source II slightly shifted to the right above) (BSH)