Highly Toxic Chlorobiphenyl and By-Side Impurities Content and Composition of Technical Chlorofen Formulation

Non- and mono-ortho CBs as well as also highly toxic by-side impurities such as chlorodibenzofurans, chlorodibenzo-p-dioxins, and chloronaphthalenes after a subsequent 2D-HPLC and HRGC-HRMS separation, detection, and identification were quantified in technical chlorobiphenyl Chlorofen formulation. Chlorofen is highly chlorinated CB mixture and its compositional profile of mono-ortho CBs is occupied by 2,3,3',4,4',5'-HxCB (no. 157) with 96.6% and followed by 2,3,3',4,4',5-HxCB (no. 156) with 3.3% and 2,3',4,4',5,5'-HxCB (no. 167) with <0.1%, while nos. 105, 114, 118, 123, and 189 remained undetected (<10 microg/g). Amongst non-ortho CBs only a trace of 3,3',4,4'-TeCB (no. 77) was found at 15 microg/g, while CBs nos. 81, 126, and 169 were absent. TCDD TEQ for mono- and non-ortho CBs in Chlorofen was 2320 and 1.5 ng/g, respectively, while for CDFs and CNs were 45 and 731 ng/g, respectively, and for both types of contaminants most contributing were OcCDF and OcCN. No tetra- to OcCDD was found in Chlorofen.