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Analytical procedure for water samples 
The principles of the analytical procedure for sea water samples are summarised in 
Figure 30; experimental details are described in the appendix (6.6.3). 
Figure 30: Overall scheme for the analysis of sea water for chlorpyrifos, endosulfan, and trifluralin 
As shown under „Validation“ (6.3.3), the procedure yields reliable results and a 
sensitivity which is better than required in the project plan. Owing to the clean base line 
of the chromatograms, sensitivity can be further increased by injecting larger volumes 
into the GC-MS. This was demonstrated for water extracts by increasing the injection 
volume from 2 pi to 10 pi, which yielded an increase in sensitivity by a factor of about 
4.