What should I do if I feel like the living conditions are not safe for an animal?

I have been doing drop-in visits for a puppy for the past weekend and finally finished them. The living situation for this dog was just beyond my comprehension. The home was incredibly dirty, and reminded me of a hoarder situation. The dog had been left in my care (twice a day 30-minute visits) and that of her boyfriend. The boyfriend appears to be leaving the dog in the crate all day, where I would routinely find pee and poop left in there. The last day of my visits, she had continued to have me come although her boyfriend was living there and he was keeping the dog in her crate all day, leaving pee and poop in there without cleaning it up, and leaving a shredded dog bed in there as well. I have been doing the best I can, but I am even afraid to be in there and the uncleanliness was haunting my dreams. I fear for the well-being of this dog, who while small, will grow to be a large dog. There is no space for this dog to live. Do I report this situation to the APL? Has anyone ever feared for the safety of a pet?