General Approach to Chemical Attack

The risk of chemical attack is no longer confined to the battlefield. The rise of asymmetric terrorist tactics, combined with the dual-use nature of technology and the proliferation of information, makes chemical terrorism a realistic threat for domestic first responders. In addition to conventional chemical warfare agents, the threat now includes the use of toxic industrial chemicals and materials that, as part of an industrial-based economy, are ubiquitous in much of developed society. Prevention, preparation, and response to such an attack requires consideration of a myriad of issues and integration across diverse disciplines to ensure optimal use of limited resources and the development of best practices. Coordination of these efforts into a cogent emergency management program requires various levels of cooperation across communities, jurisdictions, regions, states, agencies, and industries, which will improve our capabilities to respond to all hazard challenges and drive us toward better business practices. This chapter focuses on the basics of preparing for and responding to a chemical attack.

Historical perspective

Brief History

The history of chemical warfare is both rich and fascinating. An excellent summary of this topic can be found in the Textbook of Military Medicine . The modern era” of chemical warfare began during the events leading up to and surrounding World War I. In the United States, the Chemical Warfare Service was established on June 28, 1918, as part of the National Army, with responsibilities for all chemical weapons research, defense, training, medical treatment, and production facilities. The offensive weapons program was officially terminated by signature to the Chemical Weapons Convention (CWC) on January 13, 1993, with Senate approval on April 24, 1997. The existing infrastructure was converted to a strictly passive defense program. Through this infrastructure, the U.S. military has provided valuable input toward preparations for a chemical attack. This, combined with Hazardous Materials (HazMat) response work statutes from the Occupational Safety and Health Administration (OSHA) and the National Fire Protection Administration (NFPA) Guidelines governing fire and emergency services response, have served as the cornerstones of current U.S. doctrine and policy for preparation, training, and response to chemical attacks in noncombat situations. ,

The Chemical Weapons Convention

The United Nations CWC, formally titled the “Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction,” opened for signature on January 13, 1993, after 20 years of negotiation and entered into force on April 29, 1997. Signed by 182 UN member nations to date, it describes the prohibition of the use of specific chemical warfare agents, production limits for study, measures to ensure compliance, and destruction of stores of chemical stockpiles. The CWC established the Organization for the Prevention of Chemical Weapons (OPCW), located in The Hague, to serve as its operational arm, conducting verification activities, ensuring implementation of convention provisions, and providing a forum for consultation and cooperation.

Chemical Agents

A chemical attack traditionally involves highly toxic chemical warfare agents that are specifically designed to cause morbidity and mortality, are produced in significant amounts, and are coupled with appropriate dispersal technologies. By definition these agents are controlled under the CWC. However, a chemical attack can also involve toxic industrial chemicals that, while not as toxic as chemical warfare agents, are more readily available in larger quantities and are less tightly controlled. Currently, approximately 125,000 chemicals are designated as a toxic industrial chemical. These agents are generally defined as a chemical, excluding chemical warfare agents, that have an LCt50 (lethal concentration for 50% of a population exposed over a given time, t ) less than 100,000 mg-min/m 3 in any mammalian species and are produced in quantities exceeding 30 tons annually at any one production facility. Of these, approximately 4600 are considered “critical,” and almost 400 are “extremely hazardous.” ,

Chemical agents can be dispersed in various forms (e.g., vapor, aerosols, smokes, liquids on surfaces, or solids) depending on the characteristics of the agent and the intended exposure route. Most large-scale hazardous chemical incidents (intentional or unintentional) occur through inhalation exposure, but other routes, such as dermal contact or ingestion of contaminated food or water could result in substantial casualties. Individual agents, their characteristics, and treatment are covered later in this section.

Current Practice

Chemical attacks may occur suddenly and unexpectedly, with only local response capabilities available to manage the early phases of the incident. A large-scale intentional chemical attack will require additional resources from the state and federal level. Each community’s preparedness efforts should begin with a thorough understanding of all the available resources and methods to rapidly mobilize them if needed. Current tactics, techniques, and procedures (TTP) for emergency management of chemical attack have evolved from a combination of response practices from emergency services, HazMat response, and military chemical warfare defense doctrine.

Various panels have developed consensus “best practices” reports and documents, many compiled and available at the Homeland Defense Information Analysis Center (HDIAC). The National Medical Response Teams (NMRT), part of the National Disaster Medical System (NDMS), under the Department of Health and Human Services (DHHS), represent civilian teams charged with responding to CBRNE mass casualty incidents (MCI), providing decontamination, medical triage, and treatment. In 1996, the military stood up the U.S. Marine Corps Chemical Biological Incident Response Force (CBIRF) to respond to mass casualty CBRNE attacks. Additionally, the Department of Defense continues to build out its National Guard CBRNE Consequence Management Enterprise, which includes 10 Homeland Response Forces, a Defense CBRNE Response Force (DCRF), 2 command and control consequence management response elements (C2CRE), 57 Weapons of Mass Destruction Civil Support Teams (WMD-CST), and 17 CBRNE-enhanced Response Force Packages (CERFP). Aligned and distributed along Federal Emergency Management Agency (FEMA) regions, the teams are located for timely response to major population centers. These teams represent model constructs for concepts of operations for their particular missions.

Doctrine and policy

National Incident Management System

Presidential Policy Directive-8 (PPD-8) for National Preparedness establishes and defines the National Preparedness Goal and National Preparedness System as a network of planning frameworks integrating incident management across critical sectors, jurisdictions, and response organizations. Federal interagency operational plans drive unity of effort through the concept of resilience in further integrating across and through sector and agency channels to state, local, tribal, and territorial governments, nongovernmental organizations, private-sector partners, and the general public. PPD-8 builds on foundations set by Homeland Security Presidential Directive-5 (HSPD-5) defining the National Incident Management System (NIMS) as the comprehensive approach in preventing, preparing for, mitigating, responding to, and recovering from domestic incidents. The Incident Command System (ICS) and Unified Command System (UCS) are used to develop a common operating picture accessible across jurisdictions and functional agencies. The approach is to be used at federal, state, local, and tribal government municipalities.

Emergency Management Programs

HSPD-5 establishes and defines the five phases of emergency management as prevention, preparedness, mitigation, response, and recovery, around which emergency management programs (EMPs) are built. Often called Disaster Response Plans, programs now encompass an “all hazards” approach to disasters. They usually include a comprehensive, overarching plan with specific plans or annexes for various incident types. For incident management response, the Hospital Incident Command System (HICS) has become the standard used by many hospitals, and the HICS organization makes program management materials readily available online. Hospital and health system personnel have significant roles and responsibilities preidentified in preparedness and response activities. Additionally, FEMA has developed standardized training for hospital-based personnel. Health care organizations should further coordinate through their EMP with local and regional partners via local emergency preparedness committees (LEPCs) or other appropriate mechanisms. These programs are further governed by The Joint Commission standards for emergency management oversight.

For chemical attacks, critical actions in pre-incident planning phases include (1) identifying first responders/first receivers for triage, treatment, and decontamination teams; (2) establishing appropriate training, exercise, and evaluation programs; (3) developing respiratory protection and supply programs; (4) identifying key suppliers and locations for chemical antidotes; and (5) drafting and testing life-cycle management programs, communication plans, operational and evacuation procedures and policies, shelter-in-place procedures, and warning and notification procedures.

The Hazard Vulnerability Analysis (HVA) assists in determining personal protective equipment (PPE) requirements and identifying other specific planning requirements. The HVA is done in conjunction with local municipal efforts. Community planning for hospitals includes coordinating with all other regional hospitals on all aspects of EMPs, including communications, mutual aid agreements, specialized treatments, alternate care facilities, cross credentialing, information management, supplies and logistics, and training exercises.

Finally, the critical step may be networking and information management links that are established during the pre-incident phases; although having a plan is important, having gone through the planning process is the critical step. Such relationships allow for rapid reorganization or self-organization of response systems under catastrophic duress, but they must be established before the incident to be effective. Hospitals should work through their LEPC.

Current standards and guidelines

The current operating standards and guidelines applicable in responding to chemical attacks present challenges on several fronts. Statutes established for either the workplace or the battlefield are less than optimal for emergency, life-saving actions in an urban MCI response. The need for multidisciplinary expertise in developing EMPs also requires that various regulatory agencies and professional societies work together in establishing pragmatic statutes and guidelines. Challenges lie in developing standards around so many unknown entities within the response requirements and the limited real-world experience of large-scale incidents. A review of the various agencies with statutory authorities demonstrates the importance of coordination and cooperation, and further details are provided elsewhere in this text.

FEMA now serves as the central integrating agency for incident management at the federal level. It plays a huge role in nearly all aspects of emergency management, including coordinating interagency planning, national training standards, best practices, incident management, grant programs, and lessons learned collection and analysis. It maintains the Lessons Learned Information Sharing (LLIS) portal, which includes the Responder Knowledge Base (RKB) and the Authorized Equipment List (AEL).

The OSHA within the Department of Labor serves as an advocate for worker safety and health by developing standards for workers and workplaces. This includes setting levels for exposure to hazardous chemicals during work cycles, as well as levels for short-term and emergency exposure. OSHA also works with the National Institute of Occupational Safety and Health (NIOSH), other federal agencies, and private industry to develop standards for general emergency planning, Hazardous Waste Operations and Emergency Response Standard (HAZWOPER), and PPE for emergency response personnel. More specific information is available in the OSHA Technical Manual.

The Code of Federal Regulations (CFR) serves as the basis for first responder safety in emergency response to chemical attack. However, OSHA recognizes that statutory code written for emergency first responders at an incident site may be too restrictive for hospital-based “first receivers” or those health care workers who receive contaminated victims at treatment facilities. Accordingly, OSHA promulgated guidelines to provide hospitals with expert consensus regarding safe response practices. In addition, incident commanders (ICs) may use their expertise and experience to make a “risk assessment” that allows responders at hospitals or at an incident site working under their supervision to deviate from standards in order to save lives.

The NFPA develops guides and recommends practices, codes, and standards for the protection of firefighters and emergency medical technicians. Standards are enforced through OSHA promulgation. For example, NFPA defines PPE Levels 1 to 4 (e.g., Level 1 being vapor-protective for hazardous chemical emergencies; Level 2 being liquid splash-protective for hazardous chemical emergencies; Level 3 being liquid splash-protective for nonemergency, nonflammable hazardous chemicals; and Level 4 being standard work clothes). These levels correspond closely to OSHA Levels A-D, respectively. NFPA also has several guidelines regarding competencies for first responders. As background, NFPA “owns” their own work as a private, nongovernmental entity developing national firefighter standards that are then adopted by OSHA as federal standards. Meanwhile, OSHA has their own, nonfirefighter regulations. In the hot zone, both levels are used, depending on who you work for (fire and emergency services, HazMat, EPA, etc.). For the most part, manufacturers develop suits that meet both criteria levels.

The NIOSH, a division of the Centers for Disease Control and Prevention (CDC), seeks to prevent work-related illness and injury by ensuring the development, certification, deployment, and use of PPE and fully integrated, intelligent ensembles. Although NIOSH establishes standards, it does not have enforcement authority. The National Personal Protective Technology Laboratory at the NIOSH partners with NFPA, OSHA, the Department of Defense (DoD), the National Institute of Standards and Technology (NIST), and the National Institute of Justice (NIJ) in the development of standards for CBRN respirators and their certification. All respirators used for response in a chemical attack must meet NIOSH certification.

The Office of Law Enforcement Standards (OLES) at NIST, part of the NIJ, works with various agencies and partners to establish objective performance standards and equipment testing programs for critical equipment. CBRNE standards development falls under the “Critical Incident Technologies” program area. Applying technical expertise and “gold standard” laboratory capabilities, OLES works with its partners to identify technical issues, develop standard testing protocols, identify testing labs, and develop standards for such things as communications interfaces for the first responder in protective equipment, tracking first responders, and networking sensors. The standards are then issued out through the appropriate agency with statutory authority, such as NIOSH, the Environmental Protection Agency (EPA), OSHA, FEMA, DoD, or DHS. The OLES also partners with the Interagency Board (IAB, see below). PPE Guidelines are promulgated through the U.S. Department of Justice Law Enforcement and Corrections Standards and Testing Program. ,

The Interagency Board for Standardization of Equipment and Interoperability (IAB), formed in the late 1998 through a partnership with DoD and FBI, ensures standardization and interoperability throughout the response community in preparing for and responding to weapons of mass destruction (WMD) incidents. Although it is not a statutory setting agency, it has an expanded stakeholder list of federal and local partners that includes statutory agencies. Its five subgroups work through a standards coordination committee, in conjunction with a science and technology committee, to develop, maintain, and update a national standardized equipment list (SEL). This SEL is maintained online currently at the IAB’s website.

Research, Development, and Support

In addition to many excellent academic research centers, the Technical Support Working Group (TSWG) conducts the U.S. interagency research and development program for combating terrorism, coordinates research and development requirements, disseminates technology information transfer, and influences basic and applied research. The CBRN Countermeasure Subgroup focuses on chemical incident response issues. The TSWG has broad representation from federal agencies and has international participation. Current projects include a comprehensive and novel look at decontamination strategies of medical casualties and development of improved PPE.

Other Departments and Agencies

Specific roles of federal agencies and departments are covered elsewhere in this textbook; however, some specific agencies merit mention here. The DHHS has several entities with relevance for chemical attack. The National Library of Medicine (NLM) provides ready, useful resources for information on chemicals. Their Chemical Hazards Emergency Medical Management (CHEMM) Web portal represents a most useful repository of all pertinent aspects of medical response to chemical incidents. They have leading-edge technology applications, including WISER (Wireless Information System for Emergency Responders), to make information portable and accessible.

The Agency for Toxic Substances and Disease Registry (ATSDR), an agency of the DHHS, serves the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and disease related to toxic substances. The ATSDR is directed by congressional mandate to perform specific functions concerning the effect on public health of hazardous substances in the environment. These functions include public health assessments of waste sites, health consultations concerning specific hazardous substances, health surveillance and registries, response to emergency releases of hazardous substances, applied research in support of public health assessments, information development and dissemination, and education and training concerning hazardous substances. ATSDR produces toxicological profiles for hazardous substances and includes them on the National Priorities List (NPL), ranked based on frequency of occurrence at the sites, toxicity, and potential for human exposure. The profiles for nearly all of the 275 toxic substances on the NPL are available at the ATSDR website. The DHHS is also home to the Public Health Emergency Medical Countermeasures Enterprise (PHEMCE), which coordinates with federal efforts to enhance preparedness for CBRN threats.

The DoD is covered in more detail in other chapters of this textbook; however, several agencies play significant roles in preparing for and responding to chemical attacks. The Research Development & Engineering Command (RDECOM), formerly known as the Soldier Biological Chemical Command (SBCCOM is the research and development arm of the U.S. Army’s Chemical Corps. RDECOM, with the Edgewood Chemical Biological Center (ECBC), applies this R&D effort to develop concepts of operations, training programs, partnering efforts across the chemical-biologic response paradigm, and providing publications addressing significant, challenging issues in chemical incident response. RDECOM also serves as the partnering test facility with NIOSH, to perform official testing of mask/filter combinations against chemical weapons for CBRN certification.

The Army Forces Command 20th Support Command (CBRNE), formerly known as Guardian Brigade, represents an expert team specializing in responding to emergency, nonlifesaving aspects of chemical incidents ; although robust, CBRNE response capability now extends to many DoD units around the nation. The U.S. Marine Corps’ CBIRF, is a rapid response, antiterrorism unit located in Indian Head, Maryland. The USMC CBRIF serves as a model for CBRNE response teams around the world. CBRIF works closely with partners at the local, state, and federal levels, as well as with private industry, to develop, evaluate, and validate best practice TTPs for “all hazards” emergency management planning, improvement of response equipment, and development of advanced training techniques related to CBRNE. The U.S. Army Medical Research Institute for Chemical Defense (USAMRICD) provides the nation’s primary medical laboratories charged with identifying chemical weapons threats and developing medical countermeasures, including antidotes, barrier creams, decontamination solutions, and chemoprophylaxis. The training arm of Institute for Chemical Defense develops and provides the chemical portion of the “gold standard” Medical Management of Chemical/Biological Casualties and the Field Management of Chemical and Biological Casualties Courses.

The Department of Homeland Security also contributes to Chemical Defense through several offices. The Office of Science and Technology coordinates research and development and supports the Chemical Security Analysis Center (CSAC), which among other things, conducts the Chemical Terrorism Risk Assessment. The DHS Office of Health Affairs Chemical Defense Program also works with state, local, and private-sector partners and recently completed National Planning Guidance for Communities for Patient Decontamination in a Mass Chemical Exposure Incident.

The response

A chemical attack will likely occur abruptly and unexpectedly, creating large numbers of casualties. From past incidents it is expected that accurate information about the cause and extent of the event will only become clear over time. Incident command will be forced to make critical decisions about all phases of the response during a period of uncertainty and limited information. The scene perimeter will only be secured after many victims leave the scene potentially contaminated and enter the health care system unannounced. Specialized response teams, mutual aid, and other resources require time to mobilize; therefore, the initial response lies on the shoulders of the local response community. Local resources are likely to become overwhelmed, and additional resources will be necessary to augment the local response capabilities. Even though it is true that many chemicals cause their effects within seconds to minutes after exposure, the efficacy of response actions extends much longer beyond several hours. Ongoing or unpredictable exposures or shifting exposure levels; effects of comorbid medical conditions, partial or improper treatments; or delayed exposures can extend the onset of symptoms. Sublethal doses combined with underlying medical conditions, extremes of age, or coincident trauma or panic can lead to significantly compromised patients. Planning and preparedness assumptions should account for both immediate and ongoing response components.

During the Iran-Iraq War of the 1980s, Iran suffered several chemical warfare mass casualty attacks utilizing nerve agents, mustard agent, or a combination of the two (and sometimes in combination with conventional artillery attacks). The Iranian health system responded to these mass casualties, adjusting strategies and procedures over time by providing medical care closer to the incident site, eventually deploying mobile medical teams to provide care at the scene. Lessons learned from published exploits of response include the need to treat early and far forward in order to confer maximal patient benefit, the need for an integrated system of care, and a rapid response to antidote therapy and recovery for mild, uncomplicated casualties.

Several factors make it difficult to predict response time requirements. Toxicity and lethality data of specific agents are derived from animal models and are not easily translatable to humans. Toxicity curves are likely affected by extremes of age, confounding medical problems, and concomitant trauma, with unknown effects on the course of poisoning and greater potential for effects of sublethal exposures. Further, the management of large-scale MCI is poorly studied, as well, particularly in a heterogeneous population. The additional site response burden of working in PPE, and having an additional decontamination step in the treatment protocol, adds another dimension of complexity. The critical point is that response time requirements and treatment outcomes are not known; they may be affected by a multitude of factors and they may be extended.

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Aug 25, 2019 | Posted by in EMERGENCY MEDICINE | Comments Off on General Approach to Chemical Attack

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