In of themselves there's nothing necessarily dangerous about chat rooms.

Yes, young girls could get involved in a chat room and start interacting with someone who misrepresents themselves as perhaps younger or misrepresents himself in some other ways, and the danger lies in the out of chat room activity more than the in the chat room activity -- the requests, the seduction, the predator preying on the naiveté of the other member and encouraging involvement outside of that chat room.