Chlorobiphenyl Constituents of Aroclor 1268, Chlorofen, Clophen T 64, KC-600, and KC-1000 Technical Formulations

Abstract

All 209 chlorobiphenyls (CBs) theoretically possible and potentially present in relatively highly chlorinated types of technical CB formulations of Aroclor 1268, Chlorofen, Clophen T 64, KC-600, and KC-1000 have been quantified using isotope dilution techniques and high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). CB constituents of Aroclor 1268, Chlorofen, Clophen T 64, KC-600, and KC-1000 could be separated, detected, identified and quantified as “bulk CBs,” using a capillary column (60 m length × 0.25 mm i.d.) coated by 8% phenyl polycarborane-siloxane (HT-8PCB, SGE, Australia) liquid phase for GC coupled to HRMS, into 111, 78, 126, 137, and 148 peaks, respectively, which covered 140, 100, 158, 169, and 180 possible CB congeners. 87, 60, 99, 110, and 121 peaks represented single CB congeners in Aroclor 1268, Chlorofen, Clophen T 64, KC-600, and KC-1000, respectively, while 34, 18, 27, 27, and 27 peaks represented 53, 40, 59, 59, and 59 co-eluting CBs. After enrichment procedures using multilayer silica beds, alumina beds, and carbon-impregnated silica beds in glass columns, all four planar non-ortho CBs and all eight mono-ortho CBs (but with the exception of CB no. 123 in Chlorofen) could be quantified in all five technical CB formulations examined. The planar non- and mono-ortho CBs content of Aroclor 1268, Chlorofen, Clophen T 64, KC-600 and KC-1000 were 6.2, 7.0, 47, 120, 470 μ g/g and 220, 410, 34,000, 12,000, 5900 μ g/g, respectively, and their 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalents (2,3,7,8-TeCDD TEQs) were 31, 390, 710, 260, 1900 ng-TEQ/g and 35, 99, 5900, 2600, 8900 ng-TEQ/g, and the total 2,3,7,8-TeCDD TEQs of planar CBs were 66, 490, 6600, 2900, and 11,000 ng-TEQ/g.