Greetings.

Several mixes not to repel, but to kill are published as effective; being two most mentioned:

• borax + powder sugar, and

• baking soda + powder sugar + water.

Proportions seem empirical; is there a best proven ratio of compounds ?

Borax labeled as sodium borate, sodium tetraborate, or disodium tetraborate. Baking soda labeled as sodium bicarbonate. Do you know a better one ? It bothers me the baking soda-in-water preparation prevents? a later in-ants-belly reaction to produce gas as it would had already reacted while being prepared. In my ignorance, how wrong am I ? Is outgassing to be induced in the ant digestive tract and not before ingesting ?

Edited July 13Jul 13 by Externet

34 minutes ago, Externet said:

Greetings.

Several mixes not to repel, but to kill are published as effective; being two most mentioned:

• borax + powder sugar, and

• baking soda + powder sugar + water.

Proportions seem empirical; is there a best proven ratio of compounds ?

Borax labeled as sodium borate, sodium tetraborate, or disodium tetraborate. Baking soda labeled as sodium bicarbonate. Do you know a better one ? It bothers me the baking soda-in-water preparation prevents? a later in-ants-belly reaction to produce gas as it would had already reacted while being prepared. In my ignorance, how wrong am I ? Is outgassing to be induced in the ant digestive tract and not before ingesting ?

You may be confusing baking soda with baking powder. The latter is a mix of baking soda and tartaric acid which, when wetted will immediately start to react and evolve CO2. Baking soda on its own, however, won’t react when wet, only when acid is introduced. From what I read, ants eat sugar mixed with baking powder and the acid in their digestive system then triggers gas production. This apparently kills them. I’m not sure how but surface tension is a big deal for tiny insects, so maybe bubbles form that block their system or something. Someone else here may know.

You need the sugar to persuade the ants to eat the stuff.

Thanks. Yes, confused them ☹️. One of these days will experiment finely ground alka seltzer + powder sugar... 😁 Until I find a sweet acid + NaHCO3. What about using baking powder + sugar powder to make their bellies explode ?

Isn't formic acid ( HCOOH ) naturally produced by ants ?

But why kill the poor creatures ?
Ants follow trails of pheromones which are left by previous ants; that's why they follow winding trails across your floor.
Wipe the floor with a mild bleach solution and they lose their way, so they don't come back to the same place.

I never studied ant anatomy, or really studied that of humans.
But I know that we can burp, and I don't see why ants would not be able to do so.
Exploding ants seems unlikely.

However, if they eat a significant amount of sodium bicarbonate, that will throw their electrolyte balance out of kilter.

Also, in many countries, compounding your own unlicensed insecticides is illegal.

1 hour ago, John Cuthber said:

I never studied ant anatomy, or really studied that of humans.
But I know that we can burp, and I don't see why ants would not be able to do so.
Exploding ants seems unlikely.

No diaphragm

“The diaphragm is what pushes out our burps. But insects don’t have body parts that allow them to push gas from their foregut out of their mouths. And this might be why insects cannot – if you’re real technical about it – burp”

https://cals.ncsu.edu/news/do-bugs-burp/

(I thought maybe surface tension was a factor, but there’s no mention of it)

1 hour ago, John Cuthber said:

I never studied ant anatomy, or really studied that of humans.
But I know that we can burp, and I don't see why ants would not be able to do so.
Exploding ants seems unlikely.

However, if they eat a significant amount of sodium bicarbonate, that will throw their electrolyte balance out of kilter.

Also, in many countries, compounding your own unlicensed insecticides is illegal.

That’s why I wondered about surface tension. Burping may be impossible if you are so small that you can’t break the surface tension on a bubble in your gut.

But I agree “exploding” ants seems a bit of an, er, stretch.

1 hour ago, exchemist said:

But I agree “exploding” ants seems a bit of an, er, stretch.

I don't know if they 'explode', but they do 'pop' a bit when you focus sunlight on them with a magnifying glass.
( yes, I was a cruel child )

Regardless of the scale, surface tension is weaker than a solid gut wall.
Borates are not very toxic acutely in humans. Not sure about insects.

1 hour ago, John Cuthber said:

Regardless of the scale, surface tension is weaker than a solid gut wall.
Borates are not very toxic acutely in humans. Not sure about insects.

Yes I don’t suggest the ant would burst, just that its insides could become blocked and it would starve from lack of nutrition or something. But I’m only speculating.

Borax probably blocks nutrient absorption. We had ants for a while in Oregon and we mixed borax with corn syrup, making a paste. It is solid enough that workers will take bits back to the colony. Larvae can eat solid or semisolid pastes and they turn some of it into a liquid which is then what the Queen eats. That's where the effectiveness really lies.

3 minutes ago, TheVat said:

Borax probably blocks nutrient absorption. We had ants for a while in Oregon and we mixed borax with corn syrup, making a paste. It is solid enough that workers will take bits back to the colony. Larvae can eat solid or semisolid pastes and they turn some of it into a liquid which is then what the Queen eats. That's where the effectiveness really lies.

AFAIK the toxicity mechanism might still be poorly understood. Last time I looked was around 10-15 years back and while there were histotoxicological studies out there, there were still big gaps in figuring out what ultimately killed the ants when exposed to boric acid. I recall that histologically there were dose-dependent morphological changes in the epithelium of the gut, potentially related to intercellular adhesion and restoration. I believe there was some speculation that this also affects water homeostasis. But the main idea is that it somehow disrupts especially the midgut of ants.

I am not sure whether there are significant advances since then, but I suspect that it could be difficult to get funding for more detailed studies.

4 hours ago, CharonY said:

AFAIK the toxicity mechanism might still be poorly understood. Last time I looked was around 10-15 years back and while there were histotoxicological studies out there, there were still big gaps in figuring out what ultimately killed the ants when exposed to boric acid.

That's my impression, too. They understand the vectors of the paste better than what it does in the gut. It sounds a bit analogous to the impairment of intestinal villi in humans in conditions like Coeliac, Crohn's or Giardia, but far more rapidly devastating of course.

24 minutes ago, TheVat said:

That's my impression, too. They understand the vectors of the paste better than what it does in the gut. It sounds a bit analogous to the impairment of intestinal villi in humans in conditions like Coeliac, Crohn's or Giardia, but far more rapidly devastating of course.

Oh yes, there are a lot of unspecific observations (e.g. necrotization of tissues) but figuring out what leads to these phenotypes is often painstaking work and often unfundable. A pity, as it can be quite interesting.

Longtime user of honey/borax and peanut butter/borax (most ants alternate their diet between sugars and proteins I'm told). The key is to not use too much borax so it kills the foragers, you're looking for a 24 to 48 hour kill time. 1 tsp borax to 2 Tbsp bait works for me.

Edited July 17Jul 17 by LuckyR

This science forum covers small things to big innovations,thats impressive.