Borax is commonly used in ant killing products, with baits such as Terro that mix it with a sugary solution. But what exactly does borax do to an ant physically? Does it eat up an ant’s digestive system, or perhaps mess around with an ant’s nervous system?
Whatever happens to the ant, it takes some time. The idea behind borax baits is that worker ants will not only consume it, but take it back to the colony to feed other ants. This means that the poison cannot be so potent as to kill the worker ants too quickly. What accounts for the delayed effect of borax on the ant? What kind of death does the ant experience when the poison really kicks in?
The exact mode of action is still open to debate. The active constituent, Boron, is a metal that is known to bind to enzymes and alter their activity. Studies seem to suggest that boron acts in cockroaches by disrupting gut enzymes, preventing digestion and starving the animal to death. The mode of action in ants is unknown but their was some evidence that it wasn’t due to direct action within the gut since food was still being absorbed. A possible explanation is that boron, which is fairly toxic to fungi and protozoa, kill essential gut microbes and prevent vitamin synthesis or gut fermentation.
I have no idea what sort of a death they experience but I would assume that it would involve the animal becoming gradually less active and eventually succumbing to disease. That’s how starvation affects most animals.
It’s worth remmebering that for termite treatments arsenic is commonly used for the same purpose, so there’s nothing magical about boron, it’s just that it has a fairly low mammalian toxicity so it’s use is widespread. You could potentially use arsenic with much better results.