The determination of degradation products of Lewisite and/or mustard gas in water by high performance liquid chromatography

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'-dihydroxyethylsulphide 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 x 4.6 mm column with 5 mu m ODS C18 after optimization of all relevant parameters. The calibration curves of CVAOA, 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, 20 mg L-1. The method may be beneficial for studying the distribution of lewisite-and/or mustard gas and their degradation products in the environment.