title: Method for the determination of three toxic non-ortho chlorine substituted coplanar PCBs in environmental samples at part-per-trillion levels.
abstract: A method has been devised combining alkali digestion, carbon chromatography and high-resolution gas chromatography for the determination of 3,3',4,4'-tetra, 3,3',4,4',5-penta, and 3,3',4,4',5,5'-hexachlorobiphenyl, the biologically active congeners of PCBs and approximate isostereomers of 2,3,7,8-TCDD. This method permits determinations of parts-per-trillion levels of these toxic residues in biological samples. Interference both from biogenic and from xenobiotic substances was reduced to extremely low levels. Using this method, 13.5 ng of 3,3'4,4'-tetrachlorobiphenyl/g, 0.89 ng of 3,3'4,4',5-pentachlorobiphenyl/g and 0.64 ng of 3,3',4,4'5,5'-hexachlorobiphenyl/g were detected on wet weight basis in the blubber of a finless porpoise. To our knowledge this is the first report on the three toxic non-ortho chlorine substituted PCB residues detected in a higher mammal in the wilderness.
mesh_terms: D000818:Animals; D004289:Dolphins; D008401:Gas Chromatography-Mass Spectrometry; D008297:Male; D011078:Polychlorinated Biphenyls / Q000032:analysis* / Q000633:toxicity; D000072317:Polychlorinated Dibenzodioxins / Q000032:analysis; D014907:Whales
chemical_list: D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls