I've got toxic damage on one focus and +poison affect on the other, and sometimes I hear the poison affect when I hit things either with dual fire or demonspine. It tends to kill quicker than I can see the affect icon, but I assume that's what it's doing.
EDIT: Just fired off Bone Shards and saw a couple of green cloudy giblets dissolve on the ground beside me. Not sure if that was a Howler or a Ravager; either way, no Afterlife for them.