Alcohol is used often in eliquids--to dilute 100% VG (alcohol or distilled water works best) or to add flavor and TH. Some flavoring concentrates are alcohol based. I hate boozy ejuices, so when I detect alcohol, I leave the bottle open for a while in hope that the alcohol will evaporate. Those are minuscule amounts, though. I wouldn't worry about polyfill--cartomizers are disposable anyway. Besides, those who like to clean their cartos often soak them in vodka (for the record, I don't clean cartomizers myself--just throw them out after they have vaporized ~10 ml of ejuice, more if they are used in a tank).