May be the same ingredient as in baby powder.
https://richsoil.com/diatomaceous-earth.jsp
I bought a pound or so on eBay. The problem was the Ants have to walk over it. In my house (plaster walls) the Ants find some crack above the floor line or come in around the windows, bathroom and kitchen cabinets. No really good place to sprinkle powder.
"When sprinkled on a bug that has an exoskeleton (such as bed bugs, ants or fleas) it compromises their waxy coating so that their innards turn into teeny tiny bug jerky. But it doesn't hurt mammals. We can eat it. We do eat it! It's in lots of grain based foods because lots of grains are stored with diatomaceous earth to keep the bugs from eating the grain!"
I also read in another source concerning Cockroaches if you mix it in food and put it out the Roaches eat it and eventually die some where as it messes with their innards. When other bugs come to eat the dead they also ingest it and it kills again and again.
If you own an apartment building they generally have Roaches. You can spread the Diatomaceous Earth (food grade) without worry of toxicity. There is an issue if it gets in your eyes some what like getting dirt in your eyes.
People mix it in Pet food as it also is supposed to kill worms.
They say you can dust your pet's body down with it and it kills fleas. I tried that with my Cats and it was difficult to apply it and you need to avoid their Eyes. Also several days later they were still scratching. Did not appear to work well.