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“So, first of all, let me assert my firm belief that the only thing we have to fear is fear itself, nameless, unreasoning, unjustified terror which paralyzes needed efforts to convert retreat into advance.”


Franklin D. Roosevelt Inaugural address, March 4, 1933


Although the term “agents of mass destruction” is often used in planning for terrorist events, in reality, few chemicals can be delivered by terrorists in the appropriate fashion to create large numbers of deaths. However, chemical-associated mass casualties do occur. The 1984 industrial accident in Bhopal, India, caused >2500 deaths and 200,000 injuries from methyl isocyanate exposure. A natural emission of carbon dioxide in Lake Nyos, Cameroon, was responsible for 1700 chemical asphyxiant deaths. Chemical terrorism can occur through acts of willful deployment, as with the sarin release in the Tokyo subway in 1995 in which 12 people died and 5500 sought medical attention. The emergency physician is more likely to encounter the accidental release of a chemical in an industrial or transportation accident. In 2005, a freight train collision in Graniteville, South Carolina, caused the release of chlorine gas that resulted in nine deaths and 511 ED visits.1 Each year, there are 15,000 episodes in which hazardous chemicals are accidentally released in the U.S.


What we have learned from these incidents is that when chemicals are released, the agents create a penumbra effect, in which true chemical emergencies occur in the epicenter and a long shadow of fear and panic arises in individuals with lower levels of exposure. Planning for chemical disasters must take into account the chemical emergency occurring near the center of any chemical release and the chaos that can ensue through fear of exposure. What makes these events overwhelming for an individual ED is the larger number of victims, who are ambulatory, frightened, and who make their own way to the hospital. Appropriate planning for management of this large, self-extricated population is paramount to the concept of disaster preparedness for chemical emergencies and perhaps even more important than specific antidotes for rare agents that might be encountered.


At the epicenter of a chemical release (hot zone) highly contaminated individuals usually succumb early. In the immediate surrounding area (warm zone), depending on the agent and the circumstances surrounding the release, are a significant number of chemically exposed individuals who require decontamination and intensive care. In the area surrounding this often are many thousands of individuals with fear of exposure and a variety of symptoms that may be difficult to directly attribute to the actual chemical released.


Solids have a fixed volume and shape, and can be bulk solids, powders, or dusts. Dust particles are visible if they are >100 micrometers in diameter; particles below this size are imperceptible to the naked eye. Most dust particles settle with time as the result of gravity; however, in a wind-blown environment or an explosion, they can be light ...

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