Benzene Highly irritating agents normally used by law enforcement for crowd control or by individuals for protection (for example, mace)

In the study, 20 healthy men, smokers whose average age was 32, took a series of single breaths of air in which levels of the irritating agent capsaicin were steadily increased.

Surfactant acts as an anti-glue factor by reducing the adhesion of mucus to the bronchial wall, in improving its transport and in providing protection against infection and irritating agents.

The warning label on the shell in this photo, posted on Acropolis Now, states: "Federal Riot Grenade Chemical Irritating Agent (CS) Warning ... Danger (...) Contents may cause severe injury if not used in accordance with the warning instruction."