Like I said
before, if your base sample contains volatile organics, then you are
distilling those right alongside the water. They will vaporize first
and condense in your collector along with your 'pure' water.
Our distiller, currently in storage, has a little hole at the top of
the tube as it leaves the boiler. The design is to allow volatiles to
slip up and away rather than staying in the vapor that is then condensed.
No, I have never visited a distillation production facility and I
have no clue as to how or if they get rid of volatile organics.