Congener-Specific Composition of Polychlorinated Naphthalenes, Coplanar PCBs, Dibenzo-p-dioxins, and Dibenzofurans in the Halowax Series

摘要

oncentrations and congener compositions of polychlo-rinated naphthalenes (PCNs), coplanar polychlorinated biphenyls (Co-PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) were determined in seven Halowax (HW) preparations. In HW1000 and 1031, low-chlorinated naphthalenes (CNs) and in HW 1051, highly chlorinated naphthalenes were dominant, whereastri- through penta-CNs were major homologues in other Halowaxes. Concentrations of Co-PCBs were in the range of 2.0-2600 ng/ g. CB 105 and 118 were dominant in all Halowaxes. Concentrations of PCDDs/DFs were in the range of 92-5900 ng/g. The 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) in Halowaxes calculated from the amounts of PCNs, Co-PCBs, and PCDDs/DFs were in the range of 2800-220 000 ng-TEQ/g. PCNs accounted for most of the total TEQs in Halowaxes, and the contribution of PCDDs/DFs and Co-PCBs to total TEQs was less than 1/1000 that of PCNs. Congeners that most significantly contributed to TEQs were CN 69,73,70, and 63. Total TEQs roughly estimated from the Japanese production of technical PCNs, 210 kg-TEQ, was about half from technical PCBs, 440 kg-TEQ on average.