The laboratory should be sterilized and the scientists executed.
“It is not far-fetched to imagine some possible technology such that, first, virtually all sufficiently advanced civilizations eventually discover it, and second, its discovery leads almost universally to existential disaster.”
http://www.centauri-dreams.org/?p=1848
About why there may be no ET’s exploring the galaxy in spaceships. They may have destroyed themselves, accidentally or otherwise, before they could.
Just put these morons in a sealed room with a broken vial of their neat little toy.