Tiny amounts of poisonous substance botulinum toxin are injected to give a youthful look.

Early formulas also used, as the analgesic ingredient, acetanilide, now known as a poisonous substance.

Barrels contained some toxic chemicals like trimethylsilyl chloride and hexamethyldisiloxane, about of a poisonous substance in each.

Conditioned taste aversion occurs when a subject associates the taste of a certain food with symptoms caused by a toxic, spoiled, or poisonous substance.

A poisonous substance may be added as an even more powerful deterrent.