Sarin is a potent nerve agent chemical weapon that was originally designed for military purposes as a fast-acting anti-personnel weapon that would kill or disable large numbers of enemy troops. Its potent toxicity, ease of deployment, and rapid degradation allow for rapid deployment by an attacking force, who can safely enter the area of deployment a short while after its release. Sarin has been produced and stockpiled by a number of countries, and large quantities of it still exist despite collective agreements to cease manufacture and destroy stockpiles. Sarin’s ease of synthesis, which is easily disseminated across the Internet, increases the risk that terrorist organizations may use sarin to attack civilians. Sarin has been used in a number of terrorist attacks in Japan, and more recently in attacks in the Middle East, where nonmilitary organizations have led much of the disaster relief and provision of medical care. In the present article, we examine and discuss the available literature on sarin’s historical use, delivery methods, chemical properties, mechanism of action, decontamination process, and treatment. We present a management guideline to assist with the recognition of an attack and management of victims by medical professionals and disaster relief organizations, specifically in resource-constrained and austere environments. (Disaster Med Public Health Preparedness. 2018;12:249–256)

Objective: To develop and apply a novel modeling approach to support medical and public health disaster planning and response using a sarin release scenario in a metropolitan environment.

Methods: An agent-based disaster simulation model was developed incorporating the principles of dose response, surge response, and psychosocial characteristics superimposed on topographically accurate geographic information system architecture. The modeling scenarios involved passive and active releases of sarin in multiple transportation hubs in a metropolitan city. Parameters evaluated included emergency medical services, hospital surge capacity (including implementation of disaster plan), and behavioral and psychosocial characteristics of the victims.

Results: In passive sarin release scenarios of 5 to 15 L, mortality increased nonlinearly from 0.13% to 8.69%, reaching 55.4% with active dispersion, reflecting higher initial doses. Cumulative mortality rates from releases in 1 to 3 major transportation hubs similarly increased nonlinearly as a function of dose and systemic stress. The increase in mortality rate was most pronounced in the 80% to 100% emergency department occupancy range, analogous to the previously observed queuing phenomenon. Effective implementation of hospital disaster plans decreased mortality and injury severity. Decreasing ambulance response time and increasing available responding units reduced mortality among potentially salvageable patients. Adverse psychosocial characteristics (excess worry and low compliance) increased demands on health care resources. Transfer to alternative urban sites was possible.

Conclusions: An agent-based modeling approach provides a mechanism to assess complex individual and systemwide effects in rare events. (Disaster Med Public Health Preparedness. 2009;3:75–87)

During the last decade, Japan has experienced the largest burden of chemical terrorism-related events in the world, including the: (1) 1994 Matsumoto sarin attack; (2) 1995 Tokyo subway sarin attack; (3) 1998 Wakayama arsenic incident; (4) 1998 Niigata sodium-azide incident; and (5) 1998 Nagano cyanide incident. Two other intentional cyanide releases in To kyo subway and railway station restrooms were thwarted in 1995. These events spurred Japan to improve the following components of its chemical disaster-response system: (1) scene demarcation; (2) emergency medical care; (3) mass decontamination; (4) personal protective equipment; (5) chemical detection; (6) information-sharing and coordination; and (7) education and training. Further advances occurred as result of potential chemical terrorist threats to the 2000 Kyushu-Okinawa G8 Summit, which Japan hosted. Today, Japan has an integrated system of chemical disaster response that involves local fire and police services, local emergency medical services (EMS), local hospitals, Japanese Self-Defense Forces, and the Japanese Poison Information Center.

Before the sarin incidents in Tokyo and Matsumoto, the Aum Shinrikyo (now Aleph) had tried to conduct bioterrorism with botulinum toxin and Bacillus anthracis. Followers of the Aum could not overcome technical difficulties inherent in developing biological weapons, and the perpetrators had not been prosecuted for their failed attempts of bioterrorism. But the Aum's biological attack revealed several shortcomings in the Japanese law that regulated biological weapons. Since the missile experiment of North Korea conducted in 1998, the Japanese government has come to consider the threat posed by biological weapons more seriously. In 2001, after the 11 September 2001 terrorist attacks and the series of anthrax letter scares in the United States of America, the Japanese government established its Five Basic Principles for Chemical and Biological Weapons Terrorism and several measures were taken at the central and local levels. Activities of the Aum have been monitored by the Public Security Investigation Agency and the National Police Agency under the Anti-Aum Law since 2000.

Although the 1995 Tokyo subway sarin attack probably was the most widely reported terrorist event in Japan to date (5,500 injured, 12 dead), the country has suffered numerous other large terrorism-related events in recent decades, including bombings of the headquarters of Mitsubishi Heavy Industries in Tokyo in 1974 (207 injured, 8 dead), the Hokkaido Prefectural Government office building in Sapporo in 1976 (80 injured, 2 dead), and the Yosakoi-Soran Festival in Sapporo in 2000 (10 injured, none dead). Japan also has experienced two other mass-casualty terrorist events involving chemical releases, including the 1994 Matsumoto sarin attack (600 injured, 7 dead) and the 1998 Wakayama arsenic incident (67 injured, 4 dead).

Until 1995, emergency management in Japan focused on planning and preparedness at the local level for the frequent disasters caused by natural events. Since that time, substantial progress has been made in advancing emergency planning and preparedness for terrorism-related events, including the designation of disaster centers in each prefecture, the implementation of several education and training programs for nuclear, biological, and chemical terrorism, and the establishment of a national Antiterrorism Office within the Ministry of Health, Labor, and Welfare.

The prediction of future disasters drives the priorities, urgencies, and perceived adequacies of disaster management, public policy, and government funding. Disasters always arise from some fundamental dysequilibrium between hazards in the environment and the vulnerabilities of human communities. Understanding the major factors that will tend to produce hazards and vulnerabilities in the future plays a key role in disaster risk assessment.

The factors tending to produce hazards in the 21st Century include population growth, environmental degradation, infectious agents (including biological warfare agents), hazardous materials (industrial chemicals, chemical warfare agents, nuclear materials, and hazardous waste), economic imbalance (usually within countries), and cultural tribalism. The factors tending to generate vulnerabilities to hazardous events include population growth, aging populations, poverty, maldistribution of populations to disaster-prone areas, urbanization, marginalization of populations to informal settlements within urban areas, and structural vulnerability.

An increasing global interconnectedness also will bring hazards and vulnerabilities together in unique ways to produce familiar disasters in unfamiliar forms and unfamiliar disasters in forms not yet imagined. Despite concerns about novel disasters, many of the disasters common today also will be common tomorrow.

The risk of any given disaster is modifiable through its manageability. Effective disaster management has the potential to counter many of the factors tending to produce future hazards and vulnerabilities. Hazard mitigation and vulnerability reduction based on a clear understanding of the complex causal chains that comprise disasters will be critical in the complex world of the 21st Century.

Kamedo is a Swedish Disaster Medicine study organization that sends observers to disaster areas anywhere in the world to study recent events, collect useful information, and identify problems relative to the practice of Disaster Medicine. The results of these investigations are published in the KAMEDO Reports, and the English versions will be published in Prehospital and Disaster Medicine.

Three of the recent reports follow: 1) KAMEDO Report 69: Ebolus Virus Epidemic in Zaire, 1995; 2) KAMEDO Report 70: The German Rescue and Emergency Organizations: a) Industrial Chemical Fire, Memmingen, Germany 23 January 1997; b) Fire at the Düsseldorf Airport, 01 April 1996; and c) Bus Accident on the Autobahn in Rosenheim, Germany; and 3) Terrorist Attack with Sarin, 20 March 1995. In addition, a catalog listing all of the KAMEDO Reports available in English is provided.