This study, conducted at the University of Tennessee's Anthropological Research Facility (ARF), describes the establishment of the Decompositional Odor Analysis (DOA) Database for the purpose of developing a man-portable, chemical sensor capable of detecting clandestine burial sites of human remains, thereby mimicking canine olfaction. This “living” database currently spans the first year and a half of burial, providing identification, chemical trends and semi-quantitation of chemicals liberated below, above and at the surface of graves 1.5 to 3.5 ft deep (0.45 to 1.0 m) for four individuals. Triple sorbent traps (TSTs) were used to collect air samples in the field and revealed eight major classes of chemicals containing 424 specific volatile compounds associated with burial decomposition. This research is the first step toward identification of an “odor signature” unique to human decomposition with projected ramifications on cadaver dog training procedures and in the development of field portable analytical instruments which can be used to locate human remains buried in shallow graves.

This study, conducted at the University of Tennessee’s Anthropological Research Facility (ARF), lists and ranks the primary chemical constituents which define the odor of decomposition of human remains as detected at the soil surface of shallow burial sites. Triple sorbent traps were used to collect air samples in the field and revealed eight major classes of chemicals which now contain 478 specific volatile compounds associated with burial decomposition. Samples were analyzed using gas chromatography‐mass spectrometry (GC‐MS) and were collected below and above the body, and at the soil surface of 1.5–3.5 ft. (0.46–1.07 m) deep burial sites of four individuals over a 4‐year time span. New data were incorporated into the previously established Decompositional Odor Analysis (DOA) Database providing identification, chemical trends, and semi‐quantitation of chemicals for evaluation. This research identifies the “odor signatures” unique to the decomposition of buried human remains with projected ramifications on human remains detection canine training procedures and in the development of field portable analytical instruments which can be used to locate human remains in shallow burial sites.

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GC-MS can provide analytical information that is most reliable for many types of organic analyses. As field-portable GC-MS analytical systems evolve, the application scenarios have diversified as well. With the development of rugged fieldable systems, these instruments were demonstrated to be usable in the harsh environment of the jungle and in chemical demilitarization or military reconnaissance situations. Continuous unattended operations of a GC-MS for 12-or 24-hour monitoring applications in the field have been shown to be possible. A real-time algorithm strategy is proposed, which can be developed to aid in the advancement of field-portable mass spectrometry applied to chemical warfare agent analysis in military vehicles and can be used to raise the standard for field data quality. Each of these capabilities is discussed with the intent on reviewing analysis situations that can be expanded because of developments in field GC-MS instrumentation. (J Am Soc Mass Spectrom 2001, 12, 683-693)

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Ion mobility spectrometry (IMS) is a valued field detection technology because of its speed and high sensitivity, but IMS cannot easily resolve analytes of interest within mixtures. Coupling gas chromatography (GC) to IMS adds a separation capability to resolve complex matrices. A GC-IONSCAN® operated in IMS and GC⁄ IMS modes was evaluated with combinations of five explosives and four interferents. In 100 explosive/interferent combinations, IMS yielded 21 false positives while GC⁄ IMS substantially reduced the occurrence of false positives to one. In addition, the results indicate that through redesign or modification of the preconcentrator there would be significant advantages to using GC⁄ IMS, such as enhancement of the linear dynamic range (LDR) in some situations. By balancing sensitivity with LDR, GC⁄ IMS could prove to be a very advantageous tool when addressing real world complex mixture situations.

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Field as well as laboratory gas chromatography-mass spectrometry (GC-MS) systems are limited in several ways. Laboratory systems with air circulation ovens are bulky, power inefficient, and have a narrow range of temperature programming rates. Commercial field-portable GC-MS systems are too heavy, and many are limited to isothermal column temperature control. A resistively heated low thermal mass (LTM) GC system has been developed that can overcome most of these limitations, offering laboratory-level performance, or better, in a small, lightweight package. A prototype LTM GC was developed and evaluated in parallel with a commercial laboratory GC-MS used as a benchmark. A series of hydrocarbons, a Grob mixture, and a drug mixture critical pair of cocaine and nortriptyline were analyzed under different chromatographic conditions, and the performance of both systems was compared in terms of speed, efficiency, temperature control, resolution, precision, and power demand. The LTM GC was found to provide performance that was equivalent to the lab-based commercial GC when conventional temperature ramp rates were used (up to 30 • C/min). The LTM GC provided additional advantages over the conventional GC system in terms of positive or negative temperature ramping rates and range, cool-down time reduction, and lower power requirements (1-5 W/m). This new GC system demonstrated a capability for a wider range of linear temperature programming rates providing analysts flexibility when performing established forensic methods. Method development and implementation of the LTM GC was successful in demonstrating GC analyses that are controllable, reproducible, and fieldable.