Sulfur mustard (HD), or bis(2-chloroethyl)sulfide, has several urinary metabolites that can be measured to assess human exposure. These metabolites include the simple hydrolysis product thiodiglycol (TDG) and its oxidative analogue, TDG-sulfoxide, as well as metabolites of the glutathione/b-lyase pathway 1,1'-sulfonylbis[2-(methyl-sulfinyl)ethane] (SBMSE) and 1-methyl-sulfinyl-2-[(methylthio)ethyl-sulfonyl]ethane (MSMTESE). Current methods focus on either the TDG or the b-lyase metabolites. We have developed a single method that measures products of both metabolic branches, with the reduced compound of SBMSE and MSMTESE, 1,1'-sulfonylbis [2(methylthio)ethane] (SBMTE), as the definitive analyte and TDG as a confirmation analyte. Sample preparation included b-glucuronidase hydrolysis for TDG-glucuronide conjugates, titanium trichloride reduction of sulfoxides to SBMTE and TDG, solid-phase extraction, and a chemical derivatization. We analyzed samples using gas chromatography-tandem mass spectrometry with quantitation using isotope-dilution calibration. The method limits of detection for TDG and SBMTE were 0.5 ng/mL and 0.25 ng/mL, respectively, with relative standard deviations of less than 10%. Urine samples from individuals with no known exposure to mustard agent HD had measurable concentrations of TDG, but no SBMTE was detected. The geometric mean concentration of TDG was 3.43 ng/mL, with concentrations ranging from < 0.5 ng/mL to 20 ng/mL.

We here report on the further development of the method comprising the pronase digestion of albumin alkylated by sulfur mustard and the subsequent mass spectrometric analysis of an adducted tripeptide. This includes significant improvements in both the albumin isolation procedure and the automation of the microliquid chromatography-electrospray-tandem mass spectrometric analysis. We also report on the results of a small reference range study, in which we have established that there are no detectable interferences in sera from unexposed individuals.

]In July 2004, two individuals developed blisters after the destruction of a WWl-era munition. To determine the causative agent, urine samples were collected from both the highly blistered patient (patient 1; 6.5% of total body surface area) and patient 2, who had only one small blister. Their urine was analyzed for metabolites of known vesicants including sulfur mustard (HD), Lewisite (L1), and nitrogen mustards. The urine samples only tested positive for metabolites of HD. Additional metabolites were measured to confirm the exposure of sulfur mustard agent HD, including thiodiglycol (TDG), TDG-sulfoxide, and the bismercapturate of mustard sulfone. On day 2 after the exposure, patient I had a lS-lyase metabolite level of 41 ng/mL, and patient 2 had a level of 2.6 ng/mt. Detectable levels of the ~-Iyase metabolite were observed in patient 1 for 11 days and in patient 2 for 7 days. Levels of TDG and both TDG and its sulfoxide measured together in the urine of patient 1 were found to be 24 ng/mL and 50 ng/mL, respectively, on day 2. The bis-mercapturate of mustard sulfone was detected in patient 1 (3.1 ng/mL) on day 2 but was not detected in samples taken on subsequent days.The metabolism of HD has been studied extensively in rats (3,4). Research has identified several urinary metabolites, including the free and conjugated forms of the simple hydrolysis product thiodiglycol (TDG) and TDG-sulfoxide (TDG's oxidized form), the glutathione-derived metabolite 1,1'-sul- fonylbis[2-S-(N-acetylcysteinyl)ethane], and the I~-lyase metabolites 1,1'-sulfonylbis[2-(methylsulfinyl)ethane] (SBMSE) and 1-methylsulfinyl-2-[2-(methylthio)-ethylsulfonyl]ethane (MSMTESE). Although 1,]'-sulfonylbis[2-(methylthio)ethane] (SBMTE)was not identified in rat urine, it is a likely precursor to the I~-lyase metabolites that were identified (3-8).Recently, two individuals were thought to have been exposed to HD accidentally during the destruction of a WWI-era shell (9,10). The extent of blistering between the two individuals varied. One individual (patient 1) had blisters on an estimated 6.5% of his body including his hands and forearms; the second individual (patient 2) had only one small blister (9,10). Urine samples from both individuals were analyzed to confirm that the symptoms were caused by HD exposure.

The reaction of CO with NH3 over preoxidized Rh/Si02 has been studied by infrared spectroscopy to detect surface intermediates. Two of the surface species having infrared bands at 2172 and 2225 cm"1 have been identified as RhNCO and RhOCN, respectively. This is likely the first observation of these two surface species simultaneously on a supported transition-metal catalyst. High-quality ab initio computations have been employed to aid in the band assignments.