What is the active irritant in OC spray and its primary mechanism?

• A. Oleoresin capsicum; it irritates mucous membranes and eyes by activating TRPV1 receptors
• B. Capsaicin; it blocks TRPV1 receptors
• C. CS tear gas; it irritates mucous membranes
• D. Pepper spray contains no irritant

Answer: (A)

The active irritant is oleoresin capsicum, a mixture of capsaicinoids derived from chili peppers. It causes the burning, tearing, and mucous membrane irritation because these capsaicinoids bind to and activate TRPV1 receptors on sensory nerves in the eyes, nose, and throat. This receptor is a heat/pain sensor, so its activation leads to rapid neuron depolarization and release of pain mediators, producing the characteristic intense irritation. It does not block TRPV1 receptors (that would reduce pain), and the irritant is distinct from CS tear gas; pepper spray is specifically OC-based.