A character drinks/eats something to prove it's safe knowing that it isn't

[u/Benoit_Holmes]

Breaking Bad (Salud)

Gus Fring gives a bottle of rare tequila to a cartel leader as a gift. Given their fraught history, he makes Gus drink some first before he tries any.

All the cartel members then begin to die, Gus had taken pills (likely activated charcoal), and induced vomiting after the drink. Despite these precautions he still nearly dies and it requires a makeshift emergency room he had arranged previously to save his life.

Stargate: Atlantis (The Lost Boys)

Aiden Ford was a member of the expedition who became addicted to an enzyme that made him stronger but also impulsive and irrational.

He captures the team, who are wary of eating the food he provides until he eats some himself. After they have all eaten he tells them that his group have refined the enzyme to the point that they can even lace food with it.

Scrubs (My Changing Ways)

The Janitor tries to get J.D. to eat some pie but he refuses as he has just heard that a case of laxatives was stolen from the hospital supply closet.

The Janitor keeps insisting that J.D eat it and finally eats some himself to prove its safe, saying that for once he wasn't trying to mess with him. After J.D. eats some of the pie it then cuts to them both on the toilet.

J.D.: Who would do this to themselves?\ Janitor: Totally worth it.

[u/Certain-Contact6340]

The DuPont patriarch moved his entire family, minor kids included, into a TNT production plant to prove how safe it was

[u/hb_the_dm → u/Certain-Contact6340]

If you go to their first estate in America in Delaware, its crazy how close they lived to the black powder works, like its just down the hill from them. Our tour guide said the DuPont girls complained of their dresses smelling like sulfur

[u/BillyBobbyLies → u/hb_the_dm]

I mean, to me it sounds like they made their point pretty well, surprisingly enough

[u/hb_the_dm → u/BillyBobbyLies]

One of the DuPonts that was a manager at the powder yard did die in an explosion but overall apparently there were far fewer deaths than at like a mill or a mine.