I was watching an NPR thing about moonshining and how the moonshiner ( a Little Guy nameof "Popcorn") would proof his load. He3d cut it from 180% alcohol (ethanol and propanol which are effectively the solubility limits of alcohol in air or else it merely sucks water out of the air and requires drying agents to get a higher proof "Shine").
They would cut the proof by adding spring water until the bubbles resulting from shaking, dont disappear so quickly (Apparently 100 proof is the desired alcohol level for shine). However, the 2 propanol (isopropyl alcohol) that is produced and transferred into the liquor is a function of high proof shine. SO were your alcohol made from a distillation process that was a high proof (like vodka or tequila) then you ould have a measurable amount of isopropyl alcohol in your likker.
Isopropyl is commercially produced by a bucket method with sulfuric acid and propene but it also is poroduced as a late end distillate from the production of ethanol. ASO, were I a drinkin man, Id stay away from anything with a really high proof or a likker that is naturally proofed at a reading of near 100 or higher.
Isopropyl acohol , while not deadly as methanol, is much more easily metabolized into acetone than is ethanol, and acetone has some severe liver reactions should one try an excly=usive diet of high proof alcohols.