Boric acid, mixed with an appropriate material to attract ants is a low toxicity ant killer. Mix the powder with jelly for sugar ants or peanut butter for grease ants. Even though it is pet friendly, place the bait in small jars with holes in the lid to limit access.
Boric acid mixed with the attractant works as a bait poison, so foraging ants take the food back to the colony. Each ant that eats the material then dies. In a few days, the bait kills the entire colony so there are no workers to look for food seen in the home. Pharmacies sell boric acid, typically stocking it in a powdered form with the eye care products.