Characterization of the volatile organic compounds present in the headspace of decomposing animal remains, and compared with human remains
Desert Research Institute, 2215 Raggio Parkway, Reno, NV 89512, USA. Forensic science international
(Impact Factor: 2.14).
03/2012; 220(1-3):118-25. DOI: 10.1016/j.forsciint.2012.02.007
Human Remains Detection (HRD) dogs can be a useful tool to locate buried human remains because they rely on olfactory rather than visual cues. Trained specifically to locate deceased humans, it is widely believed that HRD dogs can differentiate animal remains from human remains. This study analyzed the volatile organic compounds (VOCs) present in the headspace above partially decomposed animal tissue samples and directly compared them with results published from human tissues using established solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) methods. Volatile organic compounds present in the headspace of four different animal tissue samples (bone, muscle, fat and skin) from each of cow, pig and chicken were identified and compared to published results from human samples. Although there were compounds common to both animal and human remains, the VOC signatures of each of the animal remains differed from those of humans. Of particular interest was the difference between pigs and humans, because in some countries HRD dogs are trained on pig remains rather than human remains. Pig VOC signatures were not found to be a subset of human; in addition to sharing only seven of thirty human-specific compounds, an additional nine unique VOCs were recorded from pig samples which were not present in human samples. The VOC signatures from chicken and human samples were most similar sharing the most compounds of the animals studied. Identifying VOCs that are unique to humans may be useful to develop human-specific training aids for HRD canines, and may eventually lead to an instrument that can detect clandestine human burial sites.
Available from: Agapios Agapiou
- "The animals were prepared in a local slaughterhouse in compliance with EU regulations. During euthanasia, efforts were made to reduce blood loss, as blood plasma is considered an additional fluid Table 1 An overview of the main factors affecting the decomposition rate         . "
[Show abstract] [Hide abstract]
ABSTRACT: Field experiments were devised to mimic the entrapment conditions under the rubble of collapsed buildings aiming to investigate the evolution of volatile organic compounds (VOCs) during the early dead body decomposition stage. Three pig carcasses were placed inside concrete tunnels of a search and rescue (SAR) operational field terrain for simulating the entrapment environment after a building collapse. The experimental campaign employed both laboratory and on-site analytical methods running in parallel. The current work focuses only on the results of the laboratory method using thermal desorption coupled to comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (TD-GC×GC-TOF MS). The flow-modulated TD-GC×GC-TOF MS provided enhanced separation of the VOC profile and served as a reference method for the evaluation of the on-site analytical methods in the current experimental campaign. Bespoke software was used to deconvolve the VOC profile to extract as much information as possible into peak lists. In total, 288 unique VOCs were identified (i.e., not found in blank samples). The majority were aliphatics (172), aromatics (25) and nitrogen compounds (19), followed by ketones (17), esters (13), alcohols (12), aldehydes (11), sulfur (9), miscellaneous (8) and acid compounds (2). The TD-GC×GC-TOF MS proved to be a sensitive and powerful system for resolving the chemical puzzle of above-ground "scent of death".
Copyright © 2015 Elsevier B.V. All rights reserved.
Available from: Moshe (Mike) Dalva
- "Methods to expedite locating clandestine graves have been developed where surface clues are lacking and where the content of a potential grave is unknown              . Changes in soil properties have been examined [5,7,10,13,15–17] and volatile chemical compounds and odors that could indicate the presence of buried remains        have been identified. "
[Show abstract] [Hide abstract]
ABSTRACT: Twelve pig carcasses were buried in single, shallow and deep (30 and 90 cm, respectively) graves at an experimental site near Ottawa, Ontario, Canada, with three shallow and three deep wrapped in black plastic garbage bags. An additional six carcasses were left at the surface to decompose, three of which were bagged. Six reference pits without remains were also dug. The objective of this three-year study was to examine the biogeochemistry and utility of nitrous oxide (N2O), methane (CH4) and carbon dioxide (CO2) in grave detection and whether grave depth or cadaver condition (bagged versus bare) affected soil pore air concentrations and emission of the three gases. Graves showed significantly higher (α = 0.05) concentrations and surface fluxes of N2O and CO2 than reference pits, but there was no difference in CH4 between graves and reference pits. While CH4 decreased with depth in the soil profiles, N2O and CO2 showed a large increase compared to reference pits. Shallow graves showed significantly higher emissions and pore air concentrations of N2O and CO2 than deep graves, as did bare versus bagged carcasses.
- "Scent-detection canines are an integral tool used by many law enforcement agencies to assist in locating a range of target sources including drugs, explosives, currency, accelerants, and livingand deceasedindividuals.Canines used tolocate deceased individuals or decomposed remains are typically referred to as human remains detection dogs (HRD dogs) or cadaver-detectiondogs123.Aneedforthisspecializedgroup of scent-detection canines was recognized when police observed that search and rescue dogs had difficulty tracking an individual following death, indicating a clear behavioral distinction ofthecanines inresponsetodifferentodorsources . Theseobservationshaveinitiatedmultiplestudiesoverthepast decade to determine the chemical composition of decomposition odor and the key compounds that detection dogs utilize for scent recognition [1, 2,456789. An odor profile comprises a range of volatile organic compounds (VOCs) in a gaseous state . "
[Show abstract] [Hide abstract]
ABSTRACT: Cadaver-detection dogs are used by the police to locate missing persons, victims of homicide, and human remains following mass disasters. Training is conducted using a variety of training aids including blood which can be hours, weeks or months old and stored under variable conditions. The aim of this study was to chemically profile human blood using solid-phase microextraction coupled with gas chromatography–mass spectrometry to determine how the volatile organic compound (VOC) profile changed
over time and under variable storage conditions. The VOC profiles of fresh and degraded blood were analyzed as well as blood stored at room temperature, refrigerated, and frozen. Fresh and degraded blood samples produced distinctive VOC patterns with VOC profiles becoming more complex over time. Freezing the blood produced a complex VOC profile that was clearly discriminated from the VOC profile for blood stored at room temperature or in a refrigerator. This study highlights the importance of standardizing
the age and storage conditions when using blood as a training aid to ensure cadaver-detection dogs are
exposed to an accurate representation of the blood VOCs they may encounter at a scene.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.