An attempt to separate ethylenethiourea and ethyleneurea, degradation products of ethylenebis(dithiocarbamates), using HPLC

Ethylenethiourea (ETU) and ethyleneurea (EU) are the primary biotic and abiotic degradation products of ethylenebis(dithiocarbamate) fungicides. The analytical methods used for identification and quantification of ETU involve extraction, clean-up and derivatization. The derivatization methods do not give quantitative recoveries. In recent years, HPLC has been extensively used for analysis of polar compounds and this technique has been tried to determine the chemicals in water and soil. The limit of detection of ETU/EU was shown to be 0.1 ppm using a silica gel or chemically modified silica gel as a stationary phase and a UV detector. None of the HPLC columns like silica gel, RP-18 reverse phase, Nucleosil (CN) or cyclobond using different eluting solvent mixtures could effect satisfactory separation of ETU and EU in water or soil extracts. Because of their close structural resemblance, HPLC-based methods tested in this research have failed to satisfactorily separate the two chemicals. (author). 12 refs, 2 figs, 1 tab