101 
5.4.2.5 Chlordane concentrations 
Quantification was carried out according to the fully validated method developed by 
Karlsson et al. (1999; Karlsson el al., 2000). A detailed description of the analytical 
technique is given in appendix 1, chapter 5.6.9. The most abundant chlordane represent- 
tatives are cA/frans-chlordane (octachloro compounds) and cis/Irans-nonach 1 or 
(nonachlorinated). They were quantified in most samples from the Baltic and North Sea 
together with the main metabolite oxychlordane formed from cfs/fran.s'-chlordane. No 
samples from the northern North Atlantic were analysed, since a more comprehensive 
study already existed (see Karlsson et al., 2000 and below). 
Table 30 summarises the determined concentrations, and Figures 13 and 14 visualise the 
sum concentrations on lipid basis in sampling site maps of the North and Baltic Sea. 
Table 31 gives a survey about sum chlordane concentrations in different fish species 
from the North and Baltic Sea as reported in the literature. So far, only very few Euro 
pean studies included chlordanes, which makes the data base scarce for comparison. 
Moreover, results are sometimes given as sum concentrations, which eliminate any 
compound specific differentiation. Furthermore, chlordane compound specific concen 
trations in cod liver from the Lofot Islands are summarised in Table 32. This is the only 
study from this region so far. 
5.4.2.6 Interpretation of chlordane concentrations 
The data interpretation can be summarised as follows: 
• Sum concentrations on lipid weight basis (11-47 ng/g lw) were comparable to 
other studies of fish from the Baltic and North Sea (see Table 31). 
• No significant concentration difference (t-test) was observed between the Baltic 
(Echlordane 11.3 ± 5.1 ng/g ww) and the North Sea (10.4 ± 6.0 ng/g ww) or bet 
ween the two measuring campaigns. 
• However, compared to cod liver from the Lofot Islands (Karlsson et al., 2000), 
the chlordane compound burden was about one order of magnitude lower. This