One step clean-up and separation of chlorinated, aliphatic and polycyclic aromatic hydrocarbons in environmental samples, prior to gas chromatographic quantification

A sample preparation procedure was set up that allows simultaneous gas chromotographic determination of chlorinated hydrocarbons (CH, pesticides, PCBs), aliphatic (AH) and polycyclic aromatic hydrocarbons (PAH).Contamitants are extracted from lyophilised samples with n-hexane/dichloromethane in a sonication bath. The extract, after concentration, is eluted through a multilayer clean-up - separation column, packed with sodium sulphate, activated copper, Florisil, neutral alumina and silica. By eluting two times with <<-hexane, and once with n-hexane/dichloromethane (3:2), three fractions are obtained that contain mixtures of compounds that are quantifiable with GC-ECD (CH), GC-FID (AH, PAH) and GC-MS-SIM. Samples of sediment, paniculate matter, macroalgae, and zoobenthos from the lagoon of Venice and industrial samples have been analysed by this procedure.