Yes, you print a PLA model, put it into a bucket with sand/clay, and pour hot yummy molten metal into it.
The PLA will melt, is mostly non toxic, and you can produce metal parts in your back yard or driving lot.
At least for some applications it's easier and less dangerous.
http://3dtopo.com/lostPLA/
http://m.youtube.com/watch?v=NFnfLsr...%3DNFnfLsrSuAM