By-side impurities in chloronaphthalene mixtures of the Halowax series: all 135 chlorodibenzofurans.

One hundred twenty five congeners of CDF off 135 theoretically possible were quantified in seven of various type Halowax formulations but still 45 co-eluted under the gas chromatographic conditions applied. The total CDFs concentration of Halowax formulations was between 250 and 16,000 ng/g. The compositional profile of CDF homologue groups of the Halowaxes frequently followed a degree of chlorination of the parent chloronaphthalene mixture and an exception was Halowax 1031. The compositional profile of many isomers of trichlorodibenzofuran, found and often highly abundant, was characteristic to majority of the formulations examined, and each of them demonstrated to have its own pattern but mysterious to explain remained Halowax 1031. In term of dioxin-like toxicity the most potent due to CDFs content was Halowax 1014 with 210 ng TCDD TEQ/g and next was Halowax 1013 with 36 ng TEQ/g, while between 1.3 and 5.0 ng TEQ/g were for other formulations. A tentative estimation made implies that the net total CDFs production due to manufacture of the technical CNs in the XX century could reach an amount between 420 kg (median) and 825 kg (mean), and for most toxic dioxin-like congeners between 705 g (median) and 5700 g (mean) TCDD TEQ, while for the worst case of Halowax 1014 alone scenario it could be 750 kg of the total CDFs and 16 kg of TCDD TEQ for most toxic congeners.

By-side impurities in chloronaphthalene mixtures of the Halowax series: all 209 chlorobiphenyls.

202 congeners of chlorobiphenyl (CB) with 109 single-resolved compounds and 93 co-eluting, which represented from mono- to deca-CB were quantified as by-side impurities in all seven and of various type the technical chloronaphthalene (CN) formulations of the Halowax series. IUPAC No. 104, 145, 159, 169, 184, 186, and 188 were undetected (<0.05-<0.7 ng/g). The total CBs content of the Halowax formulations ranged between 220 and 640,000 ng/g, and lower chlorinated Halowaxes 1031 (27% Cl) and 1000 (35% Cl) were two to three orders of magnitude more contaminated with CBs than higher chlorinated Halowax 1001, 1099, 1013, 1014, and 1051 (49-70% Cl). The profile of CB homologue groups of the Halowaxes changed and followed somehow a degree of chlorination of the parent CN mixture. For Halowax 1031 and 1000, a decreasing trend in proportion from mono- to deca-CB was evident, while for Halowax 1001, 1099, 1013, 1014, and 1051 the relative proportions between the CB homologue groups varied somehow. Evidently content of lower chlorinated mono- and di-CBs highly decreased and steadily increased tri- to octa-CBs and they become dominating homologues in Halowax formulations in parallel with an increase of the content of higher molecular weight CN constituents, respectively. Among planar non- and mono-ortho CBs, total concentrations in Halowax formulations were detected in the range of 2.0-2600 ng/g, and only 3,3',4,4',5,5'-HxCB (no. 169) was undetected (<0.05ng/g). Detection of by-side CBs in technical Halowaxes demonstrate clearly that those formulations apart from a massive introduction of dioxin-like CNs become in the past also an early source of environmental pollution with CBs, which proceeded for around 20-30 years use of original CB formulations.