User blog comment:Gundam Legilis/Environmental Issues in RWBY/@comment-24901923-20150403120210

Personally, considering how important it is to keeping the Grimm at bay, I would hope that mankind would try to conserve Dust for this purpose, weaning themselves off it and using substitutes for other purposes. I would also like to hope that they would attempt to synthesize Dust, but that would be virtually impossible without understanding the natural processes that made it in the first place. They may be getting closer with Penny's artificial Aura, but the tech level for a completely synthetic soul would be far higher than we see now, so I'm guessing an Full Metal Alchemist was pulled and some poor donor had their soul, and possibly organic parts to sustain it, removed for use in Penny.