207 
The bioaccumulation potential of trifluralin becomes apparent when comparing 
concentrations in the three compartments investigated (Figure 50). The enrichment 
factor calculated for the median between water and fish liver is 28000 based on wet 
weight, and 113000 based on lipid weight. 
The observed trifluralin values are comparable to those of HCH and HCB but lower 
than the concentrations of DDT-metabolites and PCBs. Typical HCH concentrations in 
the German Bight ranged from 0.2 to 0.6 pg/kg ww in 2000; HCB had a median of 0.84 
pg/kg ww, and the sum of DDTs had a median of 3.7 pg/kg ww (BSH, 2005). 
Trifluralin is a licensed product used as a herbicide in most European countries (see 
chapter 6.2.5). Approximately 3200 t is used annually in the EU, the largest users being 
France (1600 t/a) and the UK (657 t/a) (OSPAR Background document, 2004). In 1995, 
consumption in Germany was between 100 and 200 t. This is a plausible explanation for 
the presence of trifluralin in the North Sea and Baltic Sea, with water concentrations 
peaking in winter. 
The concentrations observed in sea water are well below the level of acute toxicity 
reported for aquatic organisms, which is in the low pg/L range (chapter 2.5). Compared 
to the WFD EQS value of 30 ng/L, the trifluralin concentrations detected in sea water 
are considerably lower. 
In view of the positive findings, the BSH will determine trifluralin on a voluntary basis 
during the next two years in order to support the results of this study. Especially the 
seasonal variation and geographical distribution will be investigated in more detail. 
Thereafter, it will be decided whether trifluralin should be included as a routine 
parameter in the standard monitoring program. 
6.4.5 Pentachlorophenol (PCP) 
An HPLC-MS method was developed to analyse water samples for PCP (chapter 3.3), 
which proved to be simple and had a sensitivity that was sufficient for first screening. 
An LOQ of 0.2 ng/L was achieved for a 10 L water sample. However, this method was