Appendix D: Analytical Methods 



homogenate: anhydrous sodium sulfate: dichloromethane compared to frozen tissue. The two 

 methods of room temperature storage and shipment will work from the perspective of preserving 

 total extractable lipids. 



2. Chlorinated Pesticides 



Fused silica column capillary-gas chromatography analyses demonstrate that three months 

 storage in solvent at room temperature does not appreciably alter the concentrations of major 

 chlorinated pesticide residues of interest. 



1 . Introduction 



This method deals with the determination of selected chlorinated pesticides and PCB's in 

 marine environmental samples using high resolution gas chromatography. Several other 

 halogenated pesticides and other electron capturing organic compounds may be present in samples 

 and many of these may also be determined by this method. Prior to using the method for 

 contaminants other than the compounds described here the analyst must test his/her own recovery 

 and analytical reproducibility for every residue quantified. Not all electron capturing residues will 

 be resistant to all of the clean up procedures described here for the analysis of DDT's and PCB's. 

 Therefore, additional information on the stability of some common pesticides using this 

 methodology is also provided. 



The high separation power of open tubular ("capillary") columns allows the identification 

 and quantification of many compounds in the complex mixtures occuring in environmental 

 samples. This manual provides information on the theoretical and practical aspects of the use of 

 these high resolution columns for the analysis of DDT's and PCB's in environmental samples. 



The qualitative and quantitative method can be applied to any sample type (aerosol/vapor, 

 water, particulates, biota, etc.) provided that suitable cleaned-up extracts dissolved in n-hexane are 

 available for injection into the GC systems. 



Many of the 209 possible CB (chlorobiphenyl) congeners can now be separated from 

 interfering compounds and thus be determined as individual compounds, using one capillary 

 column only (Ballschmiter and Zell, 1980; Zell and Ballschmiter, 1978; Zell and Ballschmiter, II, 

 1980; Zell and Ballschmiter, III, 1980). SE-54 is the coating material of choice, because the 

 retention behavior of all 209 congeners has been determined for this column material. Therefore, 

 as well as determining whether CB's are present in measurable quantities and whether hot-spots 

 can be identified (similar to the possibilities offered by the use of packed column GC) additional 



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