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Formula and congener group profiles are scarce in the literature. Moreover, one has to
be cautious with comparisons due to different applied methods (see chapter 5.3.3.4).Ci2
and C13 chains dominated in sediments from Australia (Kemmlein el al., 2002) and
Lake Ontario (42-81 %, ECBR (2000)). Three of four sediments from Australia showed
also higher C15 than Cu fractions and even C16-17 were detectable (Kemmlein el al.,
2002). Higher C13 fractions were reported from sites influenced by local sources
(Marvin et al., 2003). However, Stejnarova el al. (2005) found sediments dominated by
Cu congeners.
Formula and congener profiles from selected sediments and from technical mixtures
were also compared by principal component analysis, a chemometric procedure. It
allows to identify similarities and changes due to e.g. degradation between the PCA
composition in technical products and real samples. The following technical PCA
mixtures were used as reference:
• sPCAs: Mixture with 55,5 % Cl content (Dr. Ehrenstorfer, Germany); Hordalub 17,
80 and 500 (Hoechst, Germany).
• mPCAs: Mixture with 57 % Cl (Dr. Ehrenstorfer, Germany); Hordaflex SP,
Hordalub 80EM, Chlorparaffin 40fl and 45fl (Hoechst, Germany); Cloparin 50
(Caffaro, Italy).
Figure 17 summarises the comparison of technical product and sediment compositions
on the basis of the two principal components, which explain 78 % of the total variance
for sPCA and 89 % for mPCA. The following conclusions could be drawn for sPCA:
• The technical products Hordalub 80 and the sPCA mixture 55.5 % Cl of Dr.
Ehrenstorfer had a very similar composition, which deviated from other
commercial PC As and sediments (Group 1)
• Most of the sediments formed a separate cluster (group 2), which had a certain
resemblance with the technical product Hordalub 17 despite ist lower chlorine
content of 51 %. Smaller differences within the group can be explained by the
varying dominance of Cu to C13 congeners (see also Table 36).