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4 Detection and Measurement of Chemical Agents
Pages 43-64

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From page 43...
... CHEMICAL WARFARE AGENTS IN THE ENVIRONMENT When addressing the requirement for chemical agent detection at the scene of a terrorist incident, it is important to consider who really has the responsibility for detection operations. Is it the police, the fire department, the Hazmat team, or the EMS units?
From page 44...
... For medical personnel, detection equipment may include rapid, minimally invasive or noninvasive clinical assays for various chemical agents or for the effects of the chemical agents, that is, cholinesterase inhibition. Without this ability, more individuals may be exposed, including emergency response and hospital personnel attempting to care for casualties.
From page 45...
... Chemical detection equipment currently used by Hazmat teams varies considerably by locality. For large metropolitan areas, current detectors range from adequate instrumentation to absolutely no capability for CWA detection.
From page 46...
... A comparison of the column labeled "Sensitivity" with the data of Table 4-2 reveals that for all but the most expensive of these devices, the sensitivity of most currently available Army systems is adequate for detection of the presence of immediately dangerous concentrations of chemical agents, but too low for them to be appropriate to ensure the complete health and safety of victims and responders. Many currently fielded Army chemical agent detection systems also suffer from excessive false positive alarms, a characteristic which is highly undesirable in a domestic civilian situation, especially in monitoring applications (as opposed to testing for the cause of signs and symptoms of poisoning in on or more patients)
From page 47...
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From page 50...
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From page 51...
... Page 51 TABLE 4-1 Continued Equipment Agent Sensitivity Time Cost Operations/ Maintenance/Limits Notes Viking Nerve-G, V ‹0.0001 mg/m 3 ‹10 min $100,000 Field use, but Lab quality analysis; Spectratrak Mustard-HD ‹0.003 mg/m 3 ‹10 min   85 pounds Library of 62,000 GC/MS Many others       Needs 120v AC, helium chemical signatures.           40 hours training   HP 6890 GC Nerve-G, V ‹0.0001 mg/m 3 ‹10 min $50,000 Not designed for State-of-the-art gas with flame Mustard-HD ‹0.0006 mg/m 3 ‹10 min   field use chromatograph; photometric Many others       Gas, air, 220v AC Used by CWC treaty lab.
From page 52...
... Electrochemical detectors are used in mobile detectors to detect blister, nerve, blood, and choking agents. Inflame photometry, an air sample is burned in a hydrogen-rich flame.
From page 53...
... Multiple sensor arrays with multiple coatings and pattern recognition algorithms provide the means to identify agent classes and reject interferant responses that could cause false alarms. Acoustic wave sensors are used in mobile detectors to detect nerve and blister agents.
From page 54...
... Raman spectroscopy appears not to be applicable for detecting CWA precursors and degradation products in soil samples but has applicability in air samples. Mass Spectrometry (MS)
From page 55...
... have purchased M8 and M9 detection paper, M256A1 Detection Kits, M18 Detection Kits, Draegar kits, portable surface-acoustical-wave (SAW) chemical agent detectors (SAW MiniCAD)
From page 56...
... These tests were performed at a variety of concentrations and humidity levels. There were no significant effects noted due to the changes in the humidity levels for any of the chemical agents tested.
From page 57...
... The photo-ionization detector, the ion mobility detector, the surface acoustic wave detector, and the calorimetric tubes give medical personnel an ability to deal with a wider array of chemicals. As a market evolves for these items of detection equipment, modifications for the civilian community will be made to simplify their usage and the costs associated with their acquisition and maintenance should decrease.
From page 58...
... The instrument is designed to be an automated, externally mounted liquid agent detector capable of detecting G nerve agent and VX and vesicant chemical agents. · The Special Operations Forces (SOF)
From page 59...
... There should be continued support for the Public Health Service efforts to equip Metropolitan Medical Strike Teams with effective and currently available chemical agent detection equipment. These detectors are reliable, relatively inexpensive, and provide for the detection of all classical chemical agents that may be utilized in a domestic terrorist incident.
From page 60...
... Because nerve agents inhibit cholinesterase activity, laboratory tests estimating the level of this activity in red blood cells or plasma are sometimes used in estimating the degree of acute exposure. However, many hospitals cannot perform this test on site.
From page 61...
... Perhaps the most promising developments for screening kits for field use are immunochemical methods utilizing various murine monoclonal antibodies to acetylcholinesterase and ELISA (Novales-Li and Priddle, 1995~. Other Methods for Detection of Nerve Agent Exposure A number of chemical methods have been used for the direct measurement of nerve agents and their metabolites in plasma and other body fluids.
From page 62...
... Efforts have been made to develop immunoassays to chemical warfare agents (Lenz et al., 1992, 1997~. Monoclonal antibodies were developed against a structural analog of soman, and, when employed in a competitive inhibition enzyme immunoassay, were capable of detecting the nerve agent at a level of 80 ng/ml.
From page 63...
... A sensitive and simple method for determining cyanide and its major metabolite, thiocyanate, in blood involved derivatization and determination by gas chromatography and mass spectrometry (Kage et al., 1996~. The detection limits of cyanide and thiocyanate were 0.01 and 0.003 mmol/ml, respectively, while the gross recovery of both compounds was 80 percent.
From page 64...
... 4-3 Develop standard operating procedures for communication of CWA detection information from first responders to Ha~mat teams, emergency medical services, and fixed medical facilities. 4-4 Direct research efforts towards the development of simplified, rapid, and inexpensive methods of determining exposure to and level of intoxication from chemical agents in clinical samples.


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