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2.2 Part: Sampling and analysis - selected pesticides 
2.2.1 Characterisation of the target compounds 
The target compounds of this project part - chlorpyrifos (-methyl and -ethyl), dicofol, 
endosulfan (I and II), pentachlorophenol (PCP) and trifluralin - are members of entirely 
different chemical compound classes and have different applications. Chlorpyrifos, 
dicofol, and endosulfan are used as insecticides, trifluralin is a herbicide, and PCP has 
been used for various pesticidal applications. All of them are listed as hazardous 
substances for priority action by either the OSPAR Commisson or under the WFD due 
to their suspected persistence and toxic properties as well as their bio accumulation 
potential. They were included in this investigation, since the information about their 
occurrence in the marine environment was considered insufficient. 
The structures of these target compounds are very different, but their feature in common 
is an intermediate polarity (log Kow 3.5 to 5) and stability against biological 
degradation. However, they are considered less persistent and bioaccumulative than 
classical pollutants such as DDT, PCB, PAH etc. Moreover, the more polar properties 
make a prediction of their environmental behaviour more difficult. 
2.2.2 Chlorpyrifos 
Chorpyrifos is a phosphorus ester insecticide. Both the methyl- and ethyl esters are in 
use (chlopyrifos-methyl, chlorpyrifos-ethyl). They are applied as a broad-spectrum 
insecticide for the treatment of grain, cotton and vegetable crops. The compound was 
introduced in 1965 and is primarily produced by Dow AgraSciences (Indianapolis, 
USA). European manufacturers are Frunol (Unna, Germany) and Point Enterprises 
(Switzerland). Annual consumption in Europe is about 1000 t. 
2.2.3 Dicofol 
Dicofol is a dichlorodiphenylmethane insecticide with a strong structural similarity to 
DDT. However, its hydroxyl group makes it more polar and less stable. Dicofol is 
banned in Germany, and has not been sold since 1995. It is not registered in most