Mass Casualties From Crowd-Control Agents

Riot-control agents such as 1-chloroacetophenone (CN), o-chlorobenzylidene malononitrile (CS), and oleoresin capsicum (OC) are short-acting, less-lethal agents used by military and law enforcement to temporarily incapacitate potentially dangerous crowds. They are commonly referred to by names such as “tear gas,” “mace,” and “pepper spray.” They produce rapid-onset sensory irritation of skin, eyes, nose, and lungs that is usually of short duration once exposure ceases. Depending on the specific agent, other effects such as gastrointestinal (GI) upset can occur as well. Excepting confined space exposure, which has the potential to cause significant respiratory distress, riot-control agents have an excellent safety profile. First responders should be trained in using and provided with adequate protective equipment, including impermeable gloves, goggles, and respirators, and hospitals should be able to implement standard decontamination protocols when treating exposed patients. Victims should be removed from the exposure scene, decontaminated with both clothing removal and copious irrigation, and given appropriate supportive care targeted at the affected organ system.