The Determination of Degradation Products of Lewisite and/or Mustard Gas in Water by High Performance Liquid Chromatography

Abstract

Lewisite (L) and mustard gas (HD) are highly toxic vesicant warfare agents that are very sparingly soluble in water and thereby converted quantitatively to the stable and soluble degradation products 2-chlorovinylarsonous acid (CVAA), 2-chloro vinylarsonic acid (CVAOA), 2,2’-dihydroxyethyl sulphide and 2,2’-dichlorodiethyl sulphoxide. A new method based on reversed-phase high performance liquid chromatography (RP-HPLC) has been developed for the simultaneous detection of CVAOA, CVAA, 2,2’-dichlorodiethyl sulphoxide, 2,2’-dihydroxyethyl sulphide. The effects of eluent and pH on the separation efficiency were studied. UV spectra of CVAOA, CVAA, 2,2’-dichlorodiethyl sulphoxide and 2,2’-dihydroxyethyl sulphide were recorded. Good separation was achieved by HPLC using a 250 × 4.6 mm column with 5 μm ODS C18 after optimization of all relevant parameters. The calibration curves ofCVAOA,CVAA, 2,2’-dichlorodiethyl sulphoxide and 2,2’-dihydroxyethyl sulphide showed high linearity over a concentration range of 5–500, 2–500, 5–500, 50–1000 mg L^–1, respectively. The detection limits at a signal-to-noise ratio of 3 were 0.001, 0.2, 2, 20mgL^–1. The method may be beneficial for studying the distribution of lewisite-and/or mustard gas and their degradation products in the environment.

Keywords: High performance liquid chromatography, 2-chlorovinylarsonic acid, -chlorovinylarsonous acid, 2,2’-dichlorodiethyl
sulphoxide, 2,2’-dihydroxyethyl sulphide.