Detection and Screening of Chemicals Related to the Chemical Weapons Convention

Abstract

Spurred by recent events, there is an ever‐growing interest in the detection of hazardous chemicals in both military and civilian contexts. The threat of chemical weapons has spread from the battlefield to cities and towns due to the threat of international terrorism. Detection of hazardous chemicals and now chemical weapons is a requirement for first responders of all sorts. While a plethora of devices and materials exist, they all have certain inherent weaknesses and no one device can be relied upon to give an unambiguous response. As usual in chemical detection, two orthogonal methods give a much higher confidence than does any single method. This article identifies hazardous chemicals identified by the Chemical Weapons Convention and provides a description of materials and devices for sensing and responding to chemical agent contamination and releases. It comparatively evaluates current and near‐term sensor options for detecting the most likely current threats. It also identifies sensor technologies that may be capable of responding to a wider range of substances (e.g., hazardous industrial chemicals and new chemical warfare agents) to provide options for coping with new threats as they develop. Previous research results on the principal background contaminants that have the potential of introducing unwanted false alarms in chemical agent detection systems are collated, and techniques that may be capable of reducing the impact of toxic material releases are suggested.

Deploying Portable Gas Chromatography–Mass Spectrometry (GC-MS) to Military Users for the Identification of Toxic Chemical Agents in Theater

“…These methods included wet-chemical methods, colorimetric tests, electrochemical sensors, photoionization detectors, and ion mobility spectrometers. 26,29,88 In other situations, samples were sent to remote laboratories, if access to such laboratories was available, for confirmatory testing. It could take days, weeks, or even months for results of testing to be returned.…”

“…These methods range from simple color tests capable of detecting different functional groups of the CWA or TIC molecule, to advanced methods such as gas chromatography-mass spectrometry (GC-MS) that can identify and even quantify the specific chemical composition of the CWA or TIC substance. [26][27][28][29] Portable GC-MS is valuable as a confirmatory method and likely offers the best potential for meeting the current and evolving analytical challenges of the military associated with CWA and TIC detection and identification in the field. First, the vapor pressure of many modern CWAs (Table I) is low and, therefore, detection limits for viable field detection and identification technologies need to be low (like they are for portable GC-MS).…”

Ditopic Chemodosimeter for Selective Detection of Nerve Agent Tabun Simulant DCNP

“…Their selective detection is of paramount importance for armed forces and first responders in order to select the correct tools for medical countermeasures on exposure to them. [1] Though, a variety of detection systems based on electrochemistry, [2] surface acoustic wave (SAW) devices, [3] micro-cantilevers, [4] photonic crystals, [5] ion mobility spectrometry, [6] enzymatic assay, [7] etc have been developed, they suffered from limitations including non portability, operational complexity, difficulty in real time monitoring, poor selectivity and sensitivity, etc.Owing to these reasons, research on the development of optical chemical sensors, measuring the changes in their optical properties (either fluorescence or color) by virtue of their interaction with nerve agents or their simulants, gained momentum as these were cheap, easy to operate, fast and portable. [8][9][10][11][12][13][14][15][16][17][18][19] Among the chromo-fluorogenic molecular sensing probes, the supramolecular sensors, involving non-covalent interactions with analyte undergo multiple interactions (multitopic approach) with the analyte leading to selective detection.…”

Detection of Chemical Warfare Agents by Colorimetric Sensor Arrays

“…Military and domestic first responders currently use multiple methods for rapid CWA detection . Portable devices used for CWA detection and identification rely on a variety of technologies, including Fourier transform infrared spectroscopy (FT-IR), Raman spectrometry, ion mobility spectrometry (IMS), and gas chromatography–mass spectrometry (GC–MS). , No single system represents an ideal fit for all samples under all conditions, particularly once systems are miniaturized and ruggedized for field use…”

“…6 Portable devices used for CWA detection and identification rely on a variety of technologies, including Fourier transform infrared spectroscopy (FT-IR), 7 Raman spectrometry, 8 ion mobility spectrometry (IMS), 9 and gas chromatography−mass spectrometry (GC− MS). 10,11 No single system represents an ideal fit for all samples under all conditions, particularly once systems are miniaturized and ruggedized for field use. 12 Alternatively, colorimetric tests capable of identifying different functional groups of the CWAs provide a simple, cost-effective option for presumptive identification.…”