Baby got ahold of the dirty sponge

I caught my 10 month with the dirty kitchen sponge I use to clean. I have no idea how long he had it in his hands nor if he happened to stick it in his mouth. When I saw him with it he only had it in his hands but I can only think the worst. He’s poisoned, he’s going to get sick, he’s going to die 😩 What signs should I be looking for? That was on Thursday and it’s now Saturday.