Who are you planning to slip it to? Actually, any number of substances will do that, depending on dose. I don't think you need to know which ones.
The substance is the same for both plants, it is an oily resin called urushiol.
By definition, Poison is a substance that can kill you if you ingest it.
it is a rare substance of a type of poison
Poison
antidote !
Antitoxin
poison
Alchohol and poison.
i think poison
poison
long term exposure to a harmful substance
A "poison" is some substance which, if ingested or injected, will compromise the function of the body's systems or chemistry - possibly leading to death.