Question: Which chemicals are most commonly classified under the title of “riot control agents”?
Answer: Chloroacetophenone (CN), chlorobenzylidenemalononitrile (CS), chloropicrin (PS), bromobenzylcyanide (CA), dibenzoxazepine (CR), and combinations of these chemicals are irritant agents that belong to a class of agents collectively known as riot control agents or “tear gas”. Of the many tear gas agents used worldwide, CN and CS are the most common. Most exposures are inhalational, ocular, or dermal and typically lead to complaints of eye, nose, and throat irritation; hacking cough; suffocation or choking sensation; and dyspnea. High-dose exposures in an enclosed space which likely occurs only rarely, may lead to the development of airway edema, non-cardiogenic pulmonary edema, and possibly respiratory arrest.
The amount and route of the exposure to tear gas and the premorbid condition of the person exposed will contribute to the time of onset and the severity of illness. For example, given a similar route of exposure, clinical effects may vary from mild to severe, depending on the concentration of tear gas to which a person has been exposed. (https://emergency.cdc.gov/agent/riotcontrol/agentpoisoning.asp; accessed September 2017)