Potential of volatile organic compounds as markers of entrapped humans for use in urban search-and-rescue operations

Volatile organic compounds (VOCs) emitted by a human body form a chemical signature capable of providing invaluable information on the physiological status of an individual and, thereby, serving as signs of life for detecting victims after natural or man-made disasters. For this review, we created a database of potential biomarkers of human presence based on literature reports on VOCs in human breath, skin emanations, blood and urine. We estimated approximate fluxes of these VOCs from the human body, and used them to predict concentrations in the vicinity of victims. We classified proposed markers in groups by potential for victim detection. The major classification discriminants were the capability of detection by portable, real-time analytical instruments and background levels of VOCs in the urban environment. We intend data summarized in this review to assist studies on the detection of humans via chemical analysis and to accelerate investigations in this area of knowledge.