"There are stories that have come to light, over the years, that make the Central Intelligence Agency look like a collection of Looney Tunes shorts. The violence, the slapstick, and the over-the-top ridiculousness of the experiments that have been conducted over the years boggle the mind. They came from the (slightly-boggled) mind of one man: Sidney Gottlieb.
When Gottlieb wasn't trying to break someone's brain, he was trying to poison people. He was the one to come up with the infamous 'poison cigar' and 'exploding seashell' gags which failed to take out Fidel Castro. When he didn't aim to kill, he simply aimed to annoy. He wanted to spray thallium on Castro's shoes. Supposedly this was to make his beard fall out, but more likely it was yet another murder plot. Thallium is an element that is so toxic it has earned the nickname of "The Poisoner's Poison," or "Inheritance Powder." Although it can be treated with dialysis or chemicals that absorb the element, thallium isn't just a depilatory.
One idea Gottlieb oversaw, meant to poison Castro, was instead used on an Iraqi general. It involved a poisoned handkerchief tucked into a suit pocket. It did not work. Another failed assassination scheme involved a tube of poisoned toothpaste meant for Patrice Lumumba, the Prime Minister of the Republic of the Congo. This toothpaste was meant to be doused with a biological agent, rather than a chemical one. This was a bit outside Gottlieb's experience, so he experimented with many different possible agents, including smallpox, tuberculosis and equine encephalis. Lumumba eventually died in 1961, the victim of an uprising against him."
The SS too had a man who experimented with drugs. His name was Dr. Mengele.