Solid sorbent collection and gas chromatographic determination of bis(2-chloroethyl)sulfide in air at trace concentrations.

This article describes a method for the quantitative determination of the toxic military agent bis(2-chloroethyl)-sulfide (or sulfur mustard) in air or other similar gases at parts-per-trillion levels. The method entails the adsorptive trapping of mustard vapor on a bed of Tenax-GC, followed by the transfer of trapped mustard to a smaller sorbent bed and the thermal desorption of the mustard into a gas chromatograph equipped with a flame photometric detector. Interference from an oxidizing gas (probably NO2) in the air is circumvented by sampling through a filter impregnated with triethanolamine (TEA) which selectively attenuates the NO2 while transmitting the mustard. The method is found to possess adequate accuracy and precision for most purposes, and the detection limit is observed to depend on the magnitude of the sample or sorbent background response rather than on instrument noise, adsorptive sampling capacity, or other fundamental limitations of the hardware.