Detection of gasoline on arson suspects' hands

An arson suspect's contact with an ignitable liquid container can leave small traces of the substance on his hands, but detecting these traces is difficult. This research paper presents a method to obtain clear gasoline detection even 3h after hands have been moistened with 50 μL of gasoline using activated charcoal strips to adsorb the ignitable liquid traces directly from the suspect's hands. Light heating of the hands to 45 °C significantly increases the ability to detect gasoline traces. This methodology is part of a system to sample a suspect's hands at the scene of crime or in a police station. Samples are taken by investigators then analyzed in a laboratory. The suggested method provides an important improvement in detection sensitivity for ignitable liquids on suspect's hands.