AN MSD-BASED METHOD FOR THE DETECTION OF CHLORINATED DIBENZO-P-DIOXINS AND CHLORINATED DIBENZOFURANS IN FISH

A stream-lined method for the detection of polychlorinated dibenzo-p-d ioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in fish sampl es is described. The samples were mechanically blended with anhydrous sodium sulphate and then packed in a glass column. The lipid fraction was eluted from the column with dichloromethane. The described extract ion technique recovered C-13-labelled surrogate spikes as effectively as a method based on acidic digestion and liquid phase extraction. Lip ids were removed from the fish extracts by size exclusion chromatograp hy followed by chromatography on a mini acid/base silica column. The e xtract was further enriched by high performance liquid chromatography (HPLC) on basic alumina and activated carbon. The analytes were identi fied and quantified by gas chromatography combined with mass selective detection. Two sets of fish samples (n = 16 & n = 6) were used to eva luate the method: surrogate recoveries ranged from 67.5% to 75.5%, and analytical precision ranged from 13.9 to 26.4%. Tritiated 2,3,7,8-T4C DD was used to conveniently trouble shoot the method.