Re: Distilling water
Actually that's an interesting idea, depending on whether your poison is real or imagined - having to do two distillations. The first boils off the poison, which you collect and dispose of. Then with a fresh flask, you collect the water that is now boiling off, leaving behind the other problematic ingredients and giving you both water that is safe to drink, and a measure of poison to do with as you will.
Could be an interesting story element, it sparked my imagination anyway when chrispenycate wrote that!