as long as you let the pipe sit long enough for the glue to dry completely, i think you should be fine. Judging by where the pipe broke, I doubt that much heat will transfer, at least enough to emit fumes from the glue. Just be careful, if you start smelling something other than weed burning put that pipe down, heh. Thats ridiculous that it broke like that though. have you thought about returning it? Pipes are not suppose to break from just tapping out the ash. Thats definitely the sign of a poorly made pipe..