Chemical agents exposure

Box 1. Multiple chemical agent exposure assessment (EARC, 2005)... 

Eventually first responder personnel on scene will have to answer the basic question Do you have an attack or not Unlike exposure to chemical agents, exposure to biological agents does not require immediate removal of victims clothing and gross decontamination. With biological agents, inhalation is the most common route of entry to a victim s contamination. 

The studies of Nishimoto et al. (1988), Yamada (1974) and Inada et al., (1978) provide strong evidence for a causal link between chemical agent exposure and cancer however, because the workers were exposed to multiple chemicals, it is not possible to state conclusively that the cancers were due solely to sulfur mustard. Furthermore, it should be noted that several possible confounding factors, such as tobacco smoking habits, preexisting health conditions, and post-exposure occupational histories of the workers, were not evaluated. In addition, SMRs themselves may not provide an accurate estimate of relative cancer risk if they do not correlate with tumor incidence rates in exposed and control groups (i.e., if social/economic or other differences between control and exposed groups result in differences in health care which affect survival rates). 

Once protected from chemical agent exposure, decontaminate by removing clothes and showering. 

The Joint Staff recently issued new guidance for chemical agent exposure (Joint Staff Memorandum MCM-0026-02, April 29, 2002) that recommends individual protective gear for other personnel in addition to military and essential civilians who support military operations. It also comments on what to do with contaminated commercial sea lift ships. 

Prehospital Setting. The most important care that the casualty receives is the care that is given within the first several minutes of a chemical attack. The conduct of the care given immediately after toxic chemical agent exposure, including the administration of antidotes, can literally mean the difference between life and death. This is not an overstatement (United States Army Medical Research Institute of Chemical Defense, June 2001). Since this care will be rendered in a warm zone, personal protective equipment (PPE) must be employed by the responder. 

C. Prophylaxis. There is currently no prophylaxis approved for human use. Ricin is not dermally active therefore, respiratory protection is the most critical means of prevention (similar to chemical agent exposure). Vaccines under development are immunogenic and confer protection against lethal aerosol exposures in animals. 

Information in other chapters in this text describes areas of ongoing work that will expand our knowledge base, thus allowing for greater ability to deal with chemical agent exposure in mass casualty situations. 

V. Treatment. For expert assistance in management of chemical agent exposures and to access pharmaceutical antidote stockpiles that may be needed, contact your local or state health agency or regional Metropolitan Medical Response System (MMRS). In addition, it an act of terrorism is suspected, contact the Federal Bureau of Investigation (FBI). 

General Dynamics (now ChemRing) has produced handheld detectors for CWAs based on DMS called JUNO. The technology is claimed to be better than the traditional (linear field drift tube) IMS devices with regard to selectivity and sensitivity. JUNO can be used with a preconcentrator and detect CWAs at miosis levels and enables users to monitor personal chemical agent exposure levels and confirm decontamination effectiveness. 

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