Sulfur mustard metabolites

R.W. Read and R.M. Black, Analysis of the sulfur mustard metabolite l,l/-sulfonylbis[2-5-(A-acetylcysteinyl)ethane] in urine by negative ion electrospray liquid chromatography-tandem mass spectrometry, J. Anal. Toxicol, 28, 352-356 (2004). 

Figure 7. Scheme for the combined analysis of urine for sulfur mustard metabolites derived from hydrolysis and the... 

Boyer AE, Ash D, Barr DB, et al. Quantitation of the sulfur mustard metabolites l,l -sulf<)nylhis 2-(methylthio)ethane] and thiodiglycol in urine using isotope-dilution gas chromatography-tandem mass spectrometry. J Anal Toxicol, 2004 28 327-332. 

Several decomposition products of chemical munition ingredients, like sulfur mustard metabolites, also require derivatization processes (Figure 10.5). In environmental and biological matrices, sulfur mustard is predominantly hydrolyzed to the more polar and less volatile... 

In the case of sulfur mustard, analysis of low molecular weight urinary metabolites suffers from the same drawback as in the case of anticholinesterases, i.e., these products are rapidly excreted and provide therefore limited retrospectivity. Similarly, the in vivo lifetime of DNA adducts of sulfur mustard are less than those of protein adducts due to repair of DNA damage. 

R.M. Black, K. Brewster, R.J. Clarke, J.L. Hambrook, J.M. Harrison and D.J. Howells, Biological fate of sulfur mustard, l,l -thiobis(2-chloroethane) isolation and identification of urinary metabolites following intraperitoneal administration to rat, Xenobiotica, 22, 405-418 (1992). 

R.M. Black and R.W. Read, Improved methodology for the detection and quantitation of urinary metabolites of sulfur mustard using gas chromatography-tandem mass spectrometry, J. Chromatogr., B, 665, 97-196 (1995). 

LC/MS/MS is an important technique for the analysis of free metabolites and covalent adducts of sulfur mustard in urine and blood. In the case of TDG and TDGO, LC/MS has not yet been able to achieve the LODs obtainable with GC/MS after derivatization. LC/MS/MS has, however, been used successfully to analyze the metabolites (20, 21) derived from an initial reaction of sulfur mustard with glutathione (see Chapter 16). The two metabolites (20), derived from the 3-lyase pathway, can be isolated from urine by SPE on a hydroxylated polystyrene-divinylbenzene polymeric cartridge. Using a sensitive triple sector quadrupole LC/MS/MS system, detection limits of O.lng/ml have been achieved using positive ESI and MRM (56). This provides a useful alternative to GC/MS/MS, which requires reduction of the sulfoxide functions with titanium trichloride. An LC/MS/MS method (detection limit lng/ml) has been developed for the analysis of the hisf N - ace ly I cysteine) metabolite (21) in urine (57). Concentration from acidified urine was achieved on... 

R.M. Black and R.W, Read, Biological fate of sulfur mustard, l,l-thiobis(2-chloroethane) identification of 3-lyase metabolites and hydrolysis products in human urine, Xenobiotica, 25, 167-173 (1995). 

A. Fidder, D. Noort, L.P.A. de Jong, H.P. Ben-schop and A.G. Hulst, N7-(2-Hydroxyethylthio-ethyl)-guanine a novel urinary metabolite following exposure to sulfur mustard, Arch. Toxicol., 70, 854-855 (1996). 

This paper will review the known metabolic pathways of CW agents, excretion profiles where these have been measured, and methods for the analysis of metabolites in urine or blood. Examples are provided of detection in cases of human exposure. The review focuses mainly on sulfur mustard and nerve agents that represent the greatest global CW threat, and for which most analytical methods have been developed. 

Figure 3. Metabolites of sulfur mustard identified by mass spectrometry, derived from an initial reaction with glutathione and metabolized by divergent mercapturic acid and (1-lyase pathways (8)...

Figure 5. Urinary excretion profiles of metabolites derived from hydrolysis and the (5-lyase pathway in the rat following cutaneous application of sulfur mustard (dose = 2 p,mol/animal, data points mean of 4 animals dotted fine = hydrolysis products, solid fine = (5-lyase metabolites). (Reproduced from the Journal of Analytical Toxicology by permission of Preston Publications A Division of Preston Industries, Inc.)...

Analytical methods have been reported for unchanged agent and six of the urinary excretion products described above. These are TDG, TDGO, the bis A-acetylcysteine conjugate (1), two 3-lyase metabolites (2) and (3), and the guanine adduct (6). These methods have been applied to animal and/or human exposures to sulfur mustard. 

Wils et al. (25,26) previously reported an entirely different approach to TDG analysis. TDG in urine was converted back to sulfur mustard by treatment with concentrated HC1. The sample treatment is less straightforward than the methods described above, but analysis as sulfur mustard is facile. Urine, plus 2H8-TDG as internal standard, was cleaned up by elution through two C18 cartridges. Concentrated HC1 was added and the sample stirred and heated at 120 °C. Nitrogen was blown over the solution and sulfur mustard isolated from the headspace by adsorption onto Tenax-TA. The method was used to detect TDG in urine from casualties of CW attacks (see below). A disadvantage of this method is that it may convert metabolites other than TDG to sulfur mustard. This is supported by the detection of relatively high levels of analytes in urine from control subjects. Vycudilik (27) used a similar procedure, but recovered the mustard by steam distillation and extraction. 

Table 1. Concentrations of metabolites found in the urine of two subjects accidentally exposed to sulfur mustard from a WW 1 munition...

Figure 8. GC/MS/MS/MRM chromatograms showing the detection of f5-lyase metabolites in urine from two casualties of sulfur mustard poisoning (Cl, 220ng/ml and C4, 5ng/ml), their absence in urine from an unexposed subject, and the internal standard (is). Samples Cl and C4 were from two Iranian subjects undergoing treatment in Ghent in 1984, collected 10 days after the exposure...

I. Sandelowsky, G.A. Simon, P. Bel, R. Barak and A. Vincze, N1 -(2-Hydroxyethylthioethyl)-4-methylimidazole (4-met-l-imid-thiodiglycol) in plasma and urine a novel metabolite following dermal exposure to sulfur mustard, Arch. Toxicol, 66, 296-297 (1992). 

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