the toxic side to the wormwood is the thujone itself. you cant really take that out of it.
there is no substantial proof that thujone is a hallucinogen. the 'special' although not really hallucinogenic effects of absinthe are from the push and pull of all of the different herbs in it on your body. you can test this idea by just macerating pure wormwood in alcohol and drinking. or making an extract out of it. all it will do is give you a headache and make you feel dizzy. (personal experience here)