197 
Figure 44: Summary of endosulfan I concentrations in different marine matrices; min - max range and 
median values 
The observed low concentrations and distribution patterns are best explained by a 
general low-level background burden with minor local sources. 
Concentrations in the river Elbe - generally the most important source of pollutant input 
to the German Bight - are low, often below the LOQ. Therefore, a distinct gradient was 
not found in the German Bight. 
Considering the low concentrations of local sources, it is remarkable that endosulfan 
was detected at all in the North Sea and Baltic Sea. In water, endosulfan concentrations 
were well above those of the classical lipophilic pollutants like HCB, DDT, PCB or 
PAHs but below HCH concentrations. 
Atmospheric transport and deposition is well documented (Carrera et al, 2002; 
Chernyak et al, 1996). Quaghebeur et al. ( 2004) reported endosulfan in rain water in 
Belgium in the range of 1 to 224 ng/L; in the time from 1997 to 2001, they observed a 
clear downward trend in concentrations.