The location of
human remains is performed primarily through the aid of cadaver detection dogs, which rely on the malodour produced through decomposition of decaying bodies. Malefactors will attempt to conceal these putrefactive odours through chemical additions such as
lime, which is also wrongly believed to accelerate decomposition and prevent the identification of the victim. Despite the frequency of
lime in forensic applications, to date no research has been performed to determine its effect on the
volatile organic compounds (VOCs) released during human decomposition. This research was therefore conducted to ascertain the effects of hydrated
lime on the VOC profile of
human remains. Two human donors were used in a field trial at the Australian Facility for Taphonomic Experimental Research (AFTER): one donor was covered with hydrated
lime, and the other had no chemical additions acting as a control. VOC samples were collected over a period of 100 days and analysed using comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS). The volatile samples were accompanied by visual observations of how decomposition progressed. The results showed that
lime application decreased the rate of decomposition and decreased total carrion insect activity.
Lime increased the abundance of VOCs during the fresh and bloat stages of decay, however the abundance of compounds plateaued during active and advanced decomposition and were much lower than those detected from the control donor. Despite this suppression of VOCs, the study found that
dimethyl disulfide and
dimethyl trisulfide, key
sulfur-containing compounds, were still produced in high quantities, and can thus still be used to locate chemically altered
human remains. Knowledge of the effects of
lime on human decomposition can inform the training of cadaver detection dogs, and ensure a greater chance at locating victims of crimes or mass disasters.