My dad uses Fun Light (a brand of Light Lemonade), which contains aspartame and acefulfam K, to kill ants. He claims that the human body can't process the artificial sweeteners and they just pass through, but that they actually are quite toxic to ants, and that ants bodies actually take it up. Trying to find out if what he said is true, I researched it a bit.
Looking around the web I have found this story in several versions:
Sucralose was discovered in 1976 by scientists from Tate & Lyle, working with researchers Leslie Hough and Shashikant Phadnis at Queen Elizabeth College (now part of King's College London).3 While researching ways to use sucrose and its synthetic derivatives, Phadnis was told to test a chlorinated sugar compound. Phadnis thought Hough asked him to 'taste' it, so he did.6 He found the compound to be exceptionally sweet.1
This is a fairly common version:
I like telling this true story since my wife is from India, and because the “discovery” of Splenda originates back to London in 1975 and a young Indian student who was doing graduate work in chemistry while studying insecticides.
The young fellow was helping on a project of looking for ways to kill insects, when one day he mis-understood the instructions from his boss, who said to be sure to “test” his efforts. He thought the instructions were to “taste” the product, and when he did as told, imagine the surprise when he reported that this highly toxic liquid was 600 times sweeter than plain old sugar.2
Saccharine and Aspartame
Artificial sweeteners are great systemic ant killers. Saccharine was discovered while research was being done to get rid of ants. Aspartame is also very effective. Because these sweeteners are soon destroyed by damp it is best to leave them powered up at various points around the house. The ants will take the sweeteners back to the nest and the nest will literally starve to death because there is no nutrition in the sweeteners but they can’t resist eating them.3
Snopes says it's wrong but there are counter-claims in the comments
User EvelynVincent says the snope article is wrong, and cites Dr Mercola
I have seen several different claims about artificial sweeteners, and how they affect ants. Some against, some for, and they are not uncommonly saying each other is wrong.
So which is it? Does any of the artificial sweeteners work as insecticide against ants?