James R. Riches

Analysis of clothing and urine from moscow theatre siege casualties reveals carfentanil and remifentanil use

On October 26, 2002, Russian Special Forces deployed a chemical aerosol against Chechen terrorists to rescue hostages in the Dubrovka theatre. Its use confirmed Russian military interest in chemicals with effects on personnel and caused 125 deaths through a combination of the aerosol and inadequate medical care. This study provides evidence from liquid chromatography-tandem mass spectrometry analysis of extracts of clothing from two British survivors, and urine from a third survivor, that the aerosol comprised a mixture of two anaesthetics--carfentanil and remifentanil--whose relative proportions this study was unable to identify. Carfentanil and remifentanil were found on a shirt sample and a metabolite called norcarfentanil was found in a urine sample. This metabolite probably originated from carfentanil.

Simultaneous measurement of tabun, sarin, soman, cyclosarin, VR, VX, and VM adducts to tyrosine in blood products by isotope dilution UHPLC-MS/MS.

This work describes a new specific, sensitive, and rapid stable isotope dilution method for the simultaneous detection of the organophosphorus nerve agents (OPNAs) tabun (GA), sarin (GB), soman (GD), cyclosarin (GF), VR, VX, and VM adducts to tyrosine (Tyr). Serum, plasma, and lysed whole blood samples (50 μL) were prepared by protein precipitation followed by digestion with Pronase. Specific Tyr adducts were isolated from the digest by a single solid phase extraction (SPE) step, and the analytes were separated by reversed-phase ultra high performance liquid chromatography (UHPLC) gradient elution in less than 2 min. Detection was performed on a triple quadrupole tandem mass spectrometer using time-triggered selected reaction monitoring (SRM) in positive electrospray ionization (ESI) mode. The calibration range was characterized from 0.100-50.0 ng/mL for GB- and VR-Tyr and 0.250-50.0 ng/mL for GA-, GD-, GF-, and VX/VM-Tyr (R(2) ≥ 0.995). Inter- and intra-assay precision had coefficients of variation of ≤17 and ≤10%, respectively, and the measured concentration accuracies of spiked samples were within 15% of the targeted value for multiple spiking levels. The limit of detection was calculated to be 0.097, 0.027, 0.018, 0.074, 0.023, and 0.083 ng/mL for GA-, GB-, GD-, GF-, VR-, and VX/VM-Tyr, respectively. A convenience set of 96 serum samples with no known nerve agent exposure was screened and revealed no baseline values or potential interferences. This method provides a simple and highly specific diagnostic tool that may extend the time postevent that a confirmation of nerve agent exposure can be made with confidence.

Fate of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX) on soil following accelerant-based fire and liquid decontamination.

In the event of alleged use of organophosphorus nerve agents, all kinds of environmental samples can be received for analysis. These might include decontaminated and charred matter collected from the site of a suspected chemical attack. In other scenarios, such matter might be sampled to confirm the site of a chemical weapon test or clandestine laboratory decontaminated and burned to prevent discovery. To provide an analytical capability for these contingencies, we present a preliminary investigation of the effect of accelerant-based fire and liquid decontamination on soil contaminated with the nerve agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). The objectives were (a) to determine if VX or its degradation products were detectable in soil after an accelerant-based fire promoted by aviation fuel, including following decontamination with Decontamination Solution 2 (DS2) or aqueous sodium hypochlorite, (b) to develop analytical methods to support forensic analysis of accelerant-soaked, decontaminated and charred soil and (c) to inform the design of future experiments of this type to improve analytical fidelity. Our results show for the first time that modern analytical techniques can be used to identify residual VX and its degradation products in contaminated soil after an accelerant-based fire and after chemical decontamination and then fire. Comparison of the gas chromatography–mass spectrometry (GC-MS) profiles of VX and its impurities/degradation products from contaminated burnt soil, and burnt soil spiked with VX, indicated that the fire resulted in the production of diethyl methylphosphonate and O,S-diethyl methylphosphonothiolate (by an unknown mechanism). Other products identified were indicative of chemical decontamination, and some of these provided evidence of the decontaminant used, for example, ethyl 2-methoxyethyl methylphosphonate and bis(2-methoxyethyl) methylphosphonate following decontamination with DS2. Sample preparation procedures and analytical methods suitable for investigating accelerant and decontaminant-soaked soil samples are presented. VX and its degradation products and/or impurities were detected under all the conditions studied, demonstrating that accelerant-based fire and liquid-based decontamination and then fire are unlikely to prevent the retrieval of evidence of chemical warfare agent (CWA) testing. This is the first published study of the effects of an accelerant-based fire on a CWA in environmental samples. The results will inform defence and security-based organisations worldwide and support the verification activities of the Organisation for the Prohibition of Chemical Weapons (OPCW), winner of the 2013 Nobel Peace Prize for its extensive efforts to eliminate chemical weapons.

The development of an analytical method for urinary metabolites of the riot control agent 2-chlorobenzylidene malononitrile (CS)

The analysis of biomedical samples such as urine and blood can provide evidence of exposure to chemicals for a range of applications including occupational exposure monitoring, detection of drugs of abuse, performance enhancement in sport and investigations of poisoning and incapacitation. This paper reports the development of an analytical method for two suspected urinary metabolites of the riot control agent 2-chlorobenzylidene malononitrile (CS): 2-chlorohippuric acid and 2-chlorobenzyl-N-acetylcysteine. 2-Chlorohippuric acid was identified in all 2h post-exposure samples from a set of urine samples taken from army recruits exposed to low levels of thermally dispersed CS during training. 2-Chlorobenzyl-N-acetylcysteine, a metabolite known to be formed in the rat, was not identified in any of the samples. The lower limit of detection (LLOD) for 2-chlorohippuric acid and 2-chlorobenzyl-N-acetylcysteine was 1ng/ml and 0.5ng/ml in pooled urine from the pre-exposed subjects. 2-Chlorohippuric acid was rapidly excreted but was detectable in the urine of 17 of the 19 subjects tested 20h after exposure.

Chemical analysis of bleach and hydroxide-based solutions after decontamination of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX)

Detailed chemical analysis of solutions used to decontaminate chemical warfare agents can be used to support verification and forensic attribution. Decontamination solutions are amongst the most difficult matrices for chemical analysis because of their corrosive and potentially emulsion-based nature. Consequently, there are relatively few publications that report their detailed chemical analysis. This paper describes the application of modern analytical techniques to the analysis of decontamination solutions following decontamination of the chemical warfare agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX). We confirm the formation of N,N-diisopropylformamide and N,N-diisopropylamine following decontamination of VX with hypochlorite-based solution, whereas they were not detected in extracts of hydroxide-based decontamination solutions by nuclear magnetic resonance (NMR) spectroscopy or gas chromatography-mass spectrometry. We report the electron ionisation and chemical ionisation mass spectroscopic details, retention indices, and NMR spectra of N,N-diisopropylformamide and N,N-diisopropylamine, as well as analytical methods suitable for their analysis and identification in solvent extracts and decontamination residues.

Potency of irritation by benzylidenemalononitriles in humans correlates with TRPA1 ion channel activation

We show that the physiological activity of solid aerosolized benzylidenemalononitriles (BMNs) including ‘tear gas’ (CS) in historic human volunteer trials correlates with activation of the human transient receptor potential ankyrin 1 ion channel (hTRPA1). This suggests that the irritation caused by the most potent of these compounds results from activation of this channel. We prepared 50 BMNs and measured their hTRPA1 agonist potencies. A mechanism of action consistent with their physiological activity, involving their dissolution in water on contaminated body surfaces, cell membrane penetration and reversible thiolation by a cysteine residue of hTRPA1, supported by data from nuclear magnetic resonance experiments with a model thiol, explains the structure–activity relationships. The correlation provides evidence that hTRPA1 is a receptor for irritants on nociceptive neurons involved in pain perception; thus, its activation in the eye, nose, mouth and skin would explain the symptoms of lachrymation, sneezing, coughing and stinging, respectively. The structure–activity results and the use of the BMNs as pharmacological tools in future by other researchers may contribute to a better understanding of the TRPA1 channel in humans (and other animals) and help facilitate the discovery of treatments for human diseases involving this receptor.

Analysis of Organophosphorus Chemicals

The major classes of organophosphorus analytes (chemical warfare agents, flame retardants, plasticisers, pesticides, herbicides, and pharmaceuticals) and their analysis are discussed with reference to the following techniques: gas chromatography–mass spectrometry, liquid chromatography–mass spectrometry, infrared spectroscopy, ultraviolet and visible spectroscopy, nuclear magnetic resonance spectroscopy, inductively coupled plasma methods and capillary electrophoresis. Characteristic mass spectral fragmentations for some organophosphorus analytes are also presented.

Painful chemistry! From barbecue smoke to riot control

Abstract Pain! Most humans feel it throughout their lives. The molecular mechanisms underlying the phenomenon are still poorly understood. This is especially true of pain triggered in response to molecules of a certain shape and reactivity present in the environment. Such molecules can interact with the sensory nerve endings of the eyes, nose, throat and lungs to cause irritation that can range from mild to severe. The ability to alert to the presence of such potentially harmful substances has been termed the ‘common chemical sense’ and is thought to be distinct from the senses of smell or taste, which are presumed to have evolved later. Barbecue a burger excessively and you self-experiment. Fatty acids present in the meat break off their glycerol anchor under the thermal stress. The glycerol loses two molecules of water and forms acrolein, whose assault on the eyes is partly responsible for the tears elicited by smoke. Yet the smell and taste of the burger are different experiences. It was this eye-watering character of acrolein that prompted its use as a warfare agent during World War I. It was one of several ‘lachrymators’ deployed to harass, and the forerunner of safer chemicals, such as ‘tear gas’ CS, developed for riot control. The history of development and mechanism of action of some sensory irritants is discussed here in relation to recent advice from the Scientific Advisory Board (SAB) of the Organisation for the Prohibition of Chemical Weapons (OPCW) on chemicals that conform to the definition of a riot control agent (RCA) under the Chemical Weapons Convention.

CHAPTER 8:Chemical Defence Against Fentanyls

Fentanyls are solid analgesic–anaesthetics used in human and veterinary medicine. The science relevant to their use in defence and security is presented in this chapter. This includes a timeline of the pharmaceutical development of fentanyls and their medicinal uses. Their rise to prominence as incapacitating agents occurred when the Russian Special Forces used a mixture of two fentanyls, carfentanil and remifentanil, to facilitate resolution of the Moscow Theatre Siege in 2002. The identification of the composition of the mixture, enabled by analysis of clothing and a urine sample from the casualties, is described. A resurgence of apparent military interest in fentanyls by some Governments underpins the importance of developing a better awareness of the dangers posed by these toxic chemicals. This chapter discusses how research about the biological effects and chemistry of fentanyls serves as an information source to support the Chemical Weapons Convention (CWC).