199
Measured concentrations in sea water were well below the level of acute toxicity
reported for aquatic organisms; the lowest NOEC was reported to be 1 ng/L (see
Chapter 6.2.3). The observed sea water concentrations of endosulfan are about ten times
lower than the WFD EQS of 0.5 ng/L.
In view of the positive findings, the BSH will determine endosulfan levels on a
voluntary basis during the next two years in order to support the results of this study.
However, because of the low absolute concentrations, it is recommended not to include
endosulfan as a routine parameter in the standard monitoring program.
6.4.4 Trifluralin
The analytical method which has been developed and validated (3.2 and 3.3) is
characterised by a very high sensitivity, which is a prerequisite to the determination of
pollutants in marine matrices. Table 80 summarises the LODs and LOQs achieved in
the different matrices.
Table 80: Limits of detection (LOD) at a signal-to-noise ratio (S/N) of 3:1 and limits of quantification
(LOQ, S/N 10:1) for Trifluralin
LOD
LOQ
Sample amount
Water
2 pg/L
7 pg/L
10 L
Sediment
0.4 ng/kg dw
1 ng/kg dw
40 g
Biota
0.03 pg/kg lw
0.1 pg/kg lw
3g
The values obtained are on the order of the levels of classical pollutants like HCH,
PCBs, DDT-metabolites or PAH presently observed in the open marine environment.
6.4.4.1 Water
Trifluralin was determined in sea water samples from the North Sea and Baltic Sea
which had been collected during 7 cruises in 2003 to 2005 (Table 95 and Table 96,
Appendix 6.8).
Trifluralin was found in most samples at concentrations from < 7 to 500 pg/L. A strong
seasonal variation was observed, with a maximum in winter.