Organic Chemical Attribution Signatures for the Sourcing of a Mustard Agent and Its Starting Materials

Abstract

Chemical attribution signatures (CAS) are being investigated for the sourcing of chemical warfare (CW) agents and their starting materials that may be implicated in chemical attacks or CW proliferation. The work reported here demonstrates for the first time trace impurities from the synthesis of tris(2-chloroethyl)amine (HN3) that point to the reagent and the specific reagent stocks used in the synthesis of this CW agent. Thirty batches of HN3 were synthesized using different combinations of commercial stocks of triethanolamine (TEA), thionyl chloride, chloroform, and acetone. The HN3 batches and reagent stocks were then analyzed for impurities by gas chromatography/mass spectrometry. All the reagent stocks had impurity profiles that differentiated them from one another. This was demonstrated by building classification models with partial least-squares discriminant analysis (PLSDA) and obtaining average stock classification errors of 2.4, 2.8, 2.8, and 11% by cross-validation for chloroform (7 stocks), thionyl chloride (3 stocks), acetone (7 stocks), and TEA (3 stocks), respectively, and 0% for a validation set of chloroform samples. In addition, some reagent impurities indicative of reagent type were found in the HN3 batches that were originally present in the reagent stocks and presumably not altered during synthesis. More intriguing, impurities in HN3 batches that were apparently produced by side reactions of impurities unique to specific TEA and chloroform stocks, and thus indicative of their use, were observed.

Gas Chromatography-Mass Spectrometry Analysis of Synthetic Opioids Belonging to the Fentanyl Class: A Review

“…[67][68][69][70][71][72][73] This emerging field, rapidly developing in analytical chemistry, has found significant application particularly in the forensic analysis of samples associated not only with fentanyls but other chemical warfare agents. [74][75][76][77][78] Throughout this review, great effort has been placed in providing a brief introduction of the synthetic methods used to construct the discussed fentanyls as well as clear schematics that describe these pathways.…”

Adduct of the blistering warfare agent sesquimustard with human serum albumin and its mass spectrometric identification for biomedical verification of exposure

“…Source attribution means to trace the agent back to a specific synthesis method, reaction batch, specific precursor chemicals, or an existing stockpile. The chemical signatures of environmental samples have been the subject of academic interest [ 51 – 54 ] but have also been used in real cases [ 55 ]. So far, biomedical samples have not been considered for source attribution for several reasons: The intact chemical agent and the potential by-products and impurities are normally no longer present in vivo.…”

Route attribution of chemical warfare agents : Retrospective classification of unknown threat samples

“…Earlier studies have focused on degradation products formed during longterm storage, for example sulfur mustard degradation products and impurities in abandoned chemical weapons [37], or sulfur mustard degradation products found in blocks from dumped munition sites in the Baltic Sea [38]. More recently, Ovenden et al [39] studied impurities in three VX batches after storage, Webster et al [40] studied sarin impurities, and Fraga et al have studied nitrogen mustard impurities related to reagent impurities [41]. The recovery of VX and its degradation products and impurities in soil after fire or decontamination has also been studied [42], and the results showed that traces of VX and related chemicals could be recovered from soil.…”