Within this study all three monochloronitrobenzenes were identified and quantified in water of the German Eight of the North Sea. The concentrations ranged from < 0.02 to 8.9 ng/L. The latter high value was found in the estuary of the River Elbe, though. Additionally, 2,5-dichloronitrobenzene and 3,4-dichloronitrobenzene were identified and quantified. The concentrations of these compounds ranged from < 0.05 to 7.7 ng/L. The major path of input for the chloronitrobenzenes to this marine area is the River Elbe. A method for quantification is described.