GAS-CHROMATOGRAPHIC DETERMINATION OF THE LEWISITE HYDROLYSATE, 2-CHLOROVINYLARSONOUS ACID, AFTER DERIVATIZATION WITH 1,2-ETHANEDITHIOL

The primary hydrolysate of the toxic military agent lewisite (2-chlorovinylarsonous acid, or CVA) can be determined in trace concentrations by gas chromatography with flame-photometric detection after the CVA has been derivatized with 1,2-ethanedithiol to form a stable cyclic disulfide. The method has been shown to be applicable to the analysis of water samples that contain CVA in low ppb (10(9)) concentrations. In addition, the method was demonstrated to be at least potentially useful for lewisite vapor determinations in air at sub-ppb levels in situations where any CVA found in the sampler can be assumed to have been formed from lewisite. Relative to the other procedures that are available for determining lewisite or CVA, this procedure is more sensitive, more specific for the analyte or simpler to perform.