AlsoTapered
Bluelighter

UK police carry out welfare checks after Canada poison arrest
A Canadian man is being held on suspicion of selling a substance linked to suicides to people worldwide.

From what I can gather, he was posting barbiturates and sodium nitrite. I have to say that the LD50 of the latter is given as is 71 mg/kg although deaths have occurred at lower concentrations. Methemoglobinemia doesn't look a RELIABLE route.
I admit to having an aversion to intentional poisoning. I've come across some crazy examples including Barry Kidston who intentionally overdosed on cocaine. That sounds a deeply nasty way to go.