[Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in C. I. violet 23 dyes and chloranils]

A simple method for the extraction and analysis of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/F) in dyes and chloranils has been developed. Five chloranil samples and a dye sample (C.I. Violet 23) were dissolved and dispersed in sulfuric acid, followed by extracting with toluene. After the clean-up by alumina, silica and Florisil columns, the PCDD/F extracts were analysed by high resolution gas chromatograph/high resolution mass spectrometry (HRGC/HRMS). It was found that the dye and its raw material contained octachlorinated dibenzodioxin/furans (OCDD/F) at 1 to 100 micrograms/g level and hexa-, hepta-congeners ng/g levels. The toxic equivalencies (TEQ) of the samples were all beyond the dangerous level. They are found to be one of the important sources of dioxins in textile fabrics. Further investigations were performed to identify their real source.