[Determination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in 2,4,5-trichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid-alkylesters and in the corresponding herbicide formulations (author's transl)].

A method is described for the determination of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) in 2,4,5-Trichlorophenoxyacetic Acid (2,4,5-T), 2,4,5-T-Akylesters and commercial herbicide formulations containing these substances. TCDD is extracted from alkaline solution with n-hexane and purified by column chromatography on silica gel and Florisil. TCDD is determined by gas-liquid chromatography with EC-detection. For TCDD-additions of 20 micron/kg to herbicide formulations recoveries of dioxin are 96--104%. The detection limit is about 5 microgram/kg 2,4,5-T.