.Boric acid is highly toxic to pets and humans, so must be applied in places where they will not be able to touch or ingest it.
Diatomaceous earth is not toxic, in fact it can be eaten without causing harm. It is included in feed mixes for various livestock to control parasites, and is also included in some concoctions for human use around digestive health as well.
Better yet is if you can find a combination product that has the diatomaceous earth (DE) combined with Sulfur. I'll go check what company makes what I use.
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