Aspartame and other fake sugars can be used as an ant killer.
That seems to be an urban legend:
"...the satirical website The Spoof ran an article called “FDA certifies Aspartame as Ant Poison“, an attempt to parody the many anti-sweetener sites that claim various sugar substitutes (aspartame, sucralose, saccharin, etc.) are toxic to humans.
Unfortunately, even if the article ended with the phrase “The story above is a satire or parody. It is entirely fictitious”, several sites took the article seriously and began to spread the information that aspartame is toxic to ants. And so a new urban legend was born!
According to Wikipedia, aspartame is not a an ant poison and cannot be used to control ants. Whatever you may believe when it comes to the effects of aspartame on humans ..., ants are not poisoned by aspartame, nor does it repel them."