Was thinking about this earlier today. Say you do a very thorough job cleaning a glass bong using isopure alcohol; to the point where there is no visible residue on the glass and *looks* spotless. Can a marijuana test kit still test positive for traces of marijuana? How accurate are basic test kits that police usually use? How clean would your piece have to be?
i wouldnt worry about it man. 91% Iso is pretty strong and if you wash your piece properly i doubt that anything would really be picked up from it. If your really paranoid do a bleach wash in addition to the iso, or would that make some sort of explosion? test first in an open area