ABSTRACT
This chapter reviews the available methodology for the gas-chromatography analysis of certain organic chemicals whose residues have been found in various samples. Polychlorinated biphenyls (PCBs) are determined by gas chromatography using the electron-capture, microcoulometric, or electrolytic conductivity detectors. Extraction of PCBs from sewage solids was made using a mixture of hexane and isopropanol and from lyophilized marine-diatom pellets with acetone. A thin-layer cleanup procedure separates tetra and octachlorodibenzo-p-dioxin from PCBs and organochlorine pesticides. For confirmation of PCB and pesticide peaks, the position of elution from liquid-chromatography cleanup columns, derivatization and observation of any altered retention times, and the response of specific detectors are helpful. Chlorinated naphthalenes are industrial chemicals with many properties and uses similar to PCBs. In a study by Vos et al. chlorinated naphthalenes and the highly toxic chlorinated dibenzofurans were identified in two commercial PCB formulations, and a toxicological evaluation was made of these impurities.
