121 
5.4.3.5 Chlordane concentrations in sediments 
Table 38 shows the results for the chlordane representatives cis/trans-nonachlov and 
cis/tmns-chlovdane. Moreover, heptachlor was determined, but was only present in two 
samples. Figure 18 visualises the levels at most of the sampling points. Quantification 
was carried out by ECNI-MS on the Hewlett-Packard system. For quality control, some 
samples from 2003 and 2004 were analysed by ECNI on two mass spectrometers 
(Varian 1200L and Hewlett-Packard MS Engine) as well as by EI-MS/MS with an ion 
trap MS. In general, results were well comparable within 10 % with exceptions of up to 
20 % mainly for the EI-MS/MS technique. 
The following conclusion can be drawn: 
• trans-Nonachlor was most dominant in the majority of sediments. This was not 
the case for literature data. However, a further control of the reference standards did 
not reveal any systematic error, and similar results were obtained for all three 
measuring techniques. Therefore, the results presented here are considered correct. 
• cis/trans-Nonachlor concentrations were about ten times higher in the Baltic Sea 
(0.12-0.46 ng/g dw) than in the North Sea (0.001-0.34 ng/g dw). No reason can be 
given. 
• cis/trans-Chlordane levels were partly higher in the North Sea than in the Baltic 
Sea, when compared on a wet weight basis. It was vice versa expressed on TOC 
content. 
• Concentrations of cis-and of trans -chlordane were comparable. 
• Very little information about chlordane concentrations in sediments is available 
in the literature. Overall, chlordane concentrations in the sediments analysed in 
this project were within the same order of magnitude as those published. 
• Strandberg et al. (1998b) found in sediments from the northern Baltic Sea somewhat 
higher concentrations of /ran.v-nonachlor (0.006-0.13 ng/g dw) compared to cis- 
nonachlor (0.03-0.05 ng/g dw) and of cis-chlordane (0.09-0.19 ng/g dw) relative to 
/ran.s-ch lordane. Heptachlor was not detectable.