Boric acid (20 mule team Borax) and pet rats...?

I have two pet rats that are very people friendly and I frequently allow them to run around my room or bathroom to play and explore. This week I found a roach climbing down my wall and I hoped to use boric acid to kill/repel them because I strongly dislike bug sprays. I was wondering if the powder will harm my rats if they walk over it, if they will even touch it, or if they will be safe. I am sprinkling a thin coat around the edge of my room and under the bed. Please dont tell me to eliminate the things that attract them because it is useless. My room is in the basement, I live next to a field, we have a drop down ceiling, and all food and water stays cleaned up. The rats dont not attract roaches either. If anythinf the amonia in their urine repels them. Amonia is toxic to roaches. Thank you.