2014 Volume 12 Issue 5 Pages 431-445
A specific dioxin composition was detected in some sediment samples collected from the highly polluted Furuayase River, Japan. The dominant tetrachlorodibenzofuran (TeCDF) congeners in the samples were 1,3,7,8- and 1,3,7,9-tetrachlorodibenzofuran (1,3,7,8-/1,3,7,9-TeCDF). To identify the sources of the pollution with the specific dioxin composition, the dioxin compositions were studied in samples of drainage discharge water, sewage discharge water, and sludge in the sewage works from four chemical factories located in Furuayase River drainage basin. The specific composition was detected in the sewage discharge water and the sludge in the sewage works of one factory. This factory had previously produced 2,4,6-trichlorophenylhydrazine (TCPH) as an intermediate in the synthesis of a photographic medicine. It was investigated whether dioxin impurities were present in commercial TCPH reagents and whether 1,3,7,8-/1,3,7,9-TeCDF by-products might be formed during manufacture of TCPH. The dioxin homologue and congener profiles from one commercial reagent were similar to those of the sewage discharge water and sludge in the sewage works from the aforementioned factory. Our results indicated a possible pathway for the generation of 1,3,7,9-TeCDF during manufacture of TCPH.