30
Therefore, no further investigations were carried out in sediments or biota. It was also
not considered to be of priority interest to decrease the LOD to the lower pg/L range. In
the river Elbe - generally the most important source of pollutant input to the German
Bight - no dicofol was found, but the degradation product dichlorobenzophenone (DCB)
was detected at concentrations up to 3.8 ng/L. However, DCB is not a specific indicator
of dicofol, since other compounds like DDT degrade to DCB as well. Dicofol is mainly
used in southern regions such as Portugal, Spain, France, Italy and Greece. Therefore, it
may be considered to be of less priority concern for the North Sea and Baltic Sea
(unless inputs of Russia, Poland or the Baltic states are of importance). The detection
limits of the analysis method applied in this study were not low enough to detect diffuse
inputs by atmospheric deposition via long range transport.
2.2.11 Pentachlorophenol in the marine environment of the North and
Baltic Seas
PCP was found in sea water of the North Sea at concentrations between <0.2 and 1
ng/L. Most values were below the LOQ. Concentrations currently observed in the
German Bight are much lower than those reported for 1988, which varied between 0.1
to 6.4 ng/L. Low values (0.1 ng/L) comparable to the results presented here had been
observed in the outer German Bight. However, 15 years ago, PCP concentrations in
coastal areas were much higher than today, which shows that the pollutant loads of
rivers (especially the Elbe) have decreased considerably during the past years.
Nevertheless, the river Elbe still is an input source of PCP to the North Sea.
Whether other input sources to the North Sea are relevant at present cannot be derived
from the data, since PCP was non-detectable in most samples. Therefore, no spatial
distribution pattern could be obtained for the North Sea. Moreover, no high mean
concentrations of PCP of 6 to 100 ng/L were found for estuarine regions as in 1983—
1997. The observed concentrations of PCP are well below the proposed WFD EQS of
200 ng/L.