Sternutator agents toxicity

Diphenylcyanoarsine (Clark I) (DA), Diphenylchloroarsine (Clark II) (DC) and Adamsite (DM) are all classified as sternutator agents because they cause extreme sneezing, coughing and vomiting. All three chemicals have very similar structures (Figure 2.4) and all contain arsenic however, the levels that cause such a violent reaction are not toxic (0.1 mg m ). Once the particles fall to the ground after dispersion, they become ineffective unless they are re-dispersed. To have any effect, the aerosols must be inhaled or absorbed by the mucous of the eyes. 

Orthochlorobenzylidene malononitrile (CS) is the most commonly used irritant for riot control purposes. Chloracetophenone (CN) is also used in some countries for this purpose in spite of its higher toxicity. A newer agent is dibenzoxazepine (CR) with which there is little experience. Arsenical smokes (sternutators) have in the past been used on the battlefield. Apart from their lachrymatory action they also provoke other effects, e.g., bron-choconstriction and emesis, and are some times referred to as vomiting agents. 

---