6 
5.2.2.1 Structures 56 
5.2.2.2 Physical properties 57 
5.2.2.3 Metabolism 57 
5.2.2.4 Toxicity 59 
5.3 Applied methodology 59 
5.3.1 State of the art of PCA analysis 59 
5.3.2 Challenges of PCA method development 61 
5.3.3 PCA method development 61 
5.3.3.1 Clean-up and gas chromatography 61 
5.3.3.2 Mass spectrometry 62 
5.3.3.3 PCA result comparability, own techniques 64 
5.3.3.4 PCA result comparability, former studies 65 
5.3.4 Quantification of PC As 66 
5.3.4.1 Applied methods 66 
5.3.4.2 Consequences for results, this study 70 
5.3.5 Selection criteria for PCA quantification techniques 70 
5.3.6 Analysis of chlordane compounds 71 
5.3.7 Method validation and quality control 72 
5.3.7.1 Limits of detection and quantification 72 
5.3.7.2 Linearity 74 
5.3.7.3 Selectivity of clean-up 75 
5.3.7.4 Blank controls 76 
5.3.7.5 Recoveries 76 
5.4 Results and discussion 80 
5.4.1 Formula and congener profiles of technical/synthesised PCAs 80 
5.4.1.1 sPCA mixtures 80 
5.4.1.2 mPCA mixtures 85 
5.4.2 PCA and chlordanes in biota 85 
5.4.2.1 Origin and characterisation of samples 85 
5.4.2.2 PCA concentrations 88 
5.4.2.3 Interpretation of PCA concentrations 94 
5.4.2.4 PCA formula and congener group profiles 96 
5.4.2.5 Chlordane concentrations 101 
5.4.2.6 Interpretation of chlordane concentrations 101 
5.4.3 PCAs and chlordanes in sediments 107 
5.4.3.1 Origin and characterisation of samples 107 
5.4.3.2 PCA concentrations 107 
5.4.3.3 Interpretation of PCA concentrations 108 
5.4.3.4 PCA formula group and congener profiles 115 
5.4.3.5 Chlordane concentrations in sediments 121 
5.4.4 PCAs in water 125 
5.5 References 126 
5.6 Appendix 1: Methodology 130 
5.6.1 Employed PCA reference standards 130 
5.6.2 Reference standards for chlordane 132 
5.6.3 Clean-up procedure for fish (PCAs and chlordanes) 132 
5.6.4 Clean-up procedure for sediments (PCAs and chlordanes) 133