Pilot Application of SEM/EDX Analysis on Suspected Cigarette Burns in a Forensic Autopsy Case of Child Abuse.

Abstract: Cigarette burn lesions present forensic scenarios that are often difficult to investigate, both from a morphological diagnostic point of view and with regard to the mode of infliction, especially if the victim is unable to speak or has died. Although there may be the suspicion for a lesion to be produced by a lit cigarette, to date one can only rely on the morphological aspects that characterize it, and there is a lack of tools to reach the most evidence-based diagnosis possible. This limitation arose when managing a forensic autopsy case of possible child abuse that resulted in the death of the child, characterized by the presence of 3 suspicious cigarette burn lesions. We therefore decided to perform scanning electron microscopy/energy-dispersive x-ray (SEM/EDX) spectrometry analysis on these lesions and on the cigarette butt found at the crime scene. At the same time, SEM/EDX was applied to the analysis of an unlit cigarette in its entirety (obtained from the same source package as the cigarette butt), a positive control skin sample with an iatrogenic cigarette burn injury, and a negative control skin sample. Among the various compounds highlighted on compositional analysis, only sulfuric anhydride (SO 3 ) and phosphoric anhydride (P 2 O 5 ) showed a highly significant distribution pattern by being found in the autopsy samples, the cigarette butt, the tobacco of the unlit cigarette, and the positive skin control. Considering this, cigarette burns appear to follow Locard's principle as well, and similarly to other lesions, SEM/EDX allowed the diagnosis of cigarette burn lesions, already suspected morphologically, to be corroborated. Therefore, SEM/EDX is confirmed as a helpful tool in forensic pathology investigations.