Reading Cadaveric Decomposition Chemistry with a New Pair of Glasses

Abstract

The chemical processes of human cadaver decomposition are complex and not well understood. The study of decomposition chemistry aims to elucidate the postmortem processes, particularly relating to the production of volatile organic compounds (VOCs) throughout the various decomposition stages. The use of thermal desorption coupled with comprehensive two‐dimensional gas chromatography time‐of‐flight mass spectrometry (TD‐GC×GC‐TOFMS) has allowed for the VOC profile of decomposition odor above pig carcasses (human analogues) to be determined. An enhanced data‐processing approach combining Fisher ratio calculations with principal component analysis assisted in the identification of the major classes of compounds that contribute to the VOC profile and their variation across decomposition stages. Detection and profiling of these VOCs is valuable for understanding the mechanisms by which human‐remains detection (HRD) dogs locate victims in mass disasters and forensic investigations.

A Comparison of One-Dimensional and Comprehensive Two-Dimensional Gas Chromatography for Decomposition Odour Profiling Using Inter-Year Replicate Field Trials

“…More recent studies have highlighted the value of employing comprehensive two-dimensional gas chromatography (GC×GC) coupled with TOFMS for the chemical profiling of decomposition odour [4,17,18,[20][21][22][23][24][25]. In GC×GC, the coupling of two columns in series with different stationary phases allows the sample to be subjected to two independent separation processes (i.e.…”

“…Furthermore, the chromatographic peaks are compressed into highly focused pulses, as a result of zone compression occurring at the modulator, enhancing peak detectability. Overall, GC×GC is a particularly valuable technique for separating complex mixtures and has been applied in many fields where conventional 1D separations are used, such as food and flavour [27,28], environmental studies [29], metabolomics [30], petroleum products [31][32][33], and forensic science [34,35], including decomposition odour profiling [4,17,18,[20][21][22][23][24][25].…”

A New Approach for the Characterization of Organic Residues from Stone Tools Using GC×GC-TOFMS

“…Overall, this technique is highly sensitive and selective and has been shown to be extremely successful in other fields of VOC measurements such as forensic taphonomy [16][17][18][19][20], arson investigation [21], breath analysis [22], food and fragrance analysis [23,24], and many others. However, in most of these applications, the quantity of the sample is higher and the age of the sample is much more recent when comparing with archaeological investigations.…”

Postmortem Internal Gas Reservoir Monitoring Using GC×GC-HRTOF-MS

“…Comprehensive two-dimensional gas chromatography (GC×GC) techniques have already been reported to be of high efficacy for the monitoring of decomposition VOCs from different matrices such as soils [7][8][9][10][11] and whole body headspace [12][13][14][15][16][17][18][19]. An increase in separation power is required to efficiently separate the hundreds of VOCs emitted by decomposing remains.…”