It will not be dangerous until a fault occurs and then it could be lethal - you might never know about it.
Electrical fittings designed to be eartherd MUST ALWAYS be earthed.
Your assertion, "there is not an earth wire there" may not be correct - have another look - pull gently on the wires and see what comes through the hole in the ceiling - If you can't find an earth then call in an electrician.
Good luck... take care...
Peccavi, November 2009