However, for gross negligence he couldn't top Michael Sveda, who was smoking in the lab and put down his cigarette on a pile of chemicals. He then picked it back up and put it in his mouth, because you gotta get that nicotine rush no matter what, and noticed-guess what!-a sweet taste. He had stumbled on cyclamate, currently found only in the Canadian version of Sweet N' Low because apparently Canada has to be different.
The crown prize of stupidity, however, has to go with sucralose (aka Splenda): A foreign grad student named Shashikant Phadnis somehow misread a request for "testing these chemicals" as "tasting these chemicals." Instead of doing the logical thing and asking the professor what the hell kind of country this was, he obediently stuffed the chemicals in his mouth. If this were a wacky college movie he would have started tripping out and trying to have sex with inanimate objects. Since it was (boring) real life, he just tasted, of course, sweetness.
...Science?