Biochemical pathways generating post-mortem volatile compounds co-detected during forensic ethanol analyses

Forensic Analysis of Volatile Organic Compounds from Decomposed Remains in a Soil Environment

“…During decomposition, the putrefactive breakdown of macromolecules produces a variety of decomposition gases including methane, carbon dioxide and hydrogen sulfi de as well as volatile organic compounds (VOCs) (Gill-King 1997 ;Dent et al 2004 ;Statheropoulos et al 2005 ;Boumba et al 2008 ). VOCs can be generally defi ned as any compound with an appreciable vapour pressure and can have a variety of chemical properties (ASTM International 2004 ).…”

“…VOCs can be generally defi ned as any compound with an appreciable vapour pressure and can have a variety of chemical properties (ASTM International 2004 ). The degradation of soft tissue produces hundreds of decomposition VOCs from numerous chemical classes including alcohols, aldehydes, alkanes/alkenes, aromatics, carboxylic acids, esters, ethers, halogens, ketones, nitrogen and sulfur compounds (Vass et al 2004 ;Statheropoulos et al 2005Statheropoulos et al , 2007Boumba et al 2008 ;Vass et al 2008 ;Dekeirsschieter et al 2009 ;DeGreeff and Furton 2011 ;Paczkowski and Schutz 2011 ;Statheropoulos et al 2011 ;Brasseur et al 2012 ;Cablk et al 2012 ;Dekeirsschieter et al 2012 ;Stadler et al 2013 ). Although similar chemical classes have been reported in a variety of studies the complexity of these samples has precluded the complete characterisation of decomposition odour (Statheropoulos et al 2011 ;Dekeirsschieter et al 2012 ).…”

“…The chemical pathways and exact origins of these compounds are uncertain however it is clear that the decomposition environment and the bacteria present during decomposition will affect their production (Boumba et al 2008 ;Dekeirsschieter et al 2009 ;Paczkowski and Schutz 2011 ;Statheropoulos et al 2011 ). Currently there is a large amount of variability in the compounds reported (DeGreeff and Furton 2011 ;Paczkowski and Schutz 2011 ).…”

“…Little is known about the microfl ora involved with decomposition, however it is known to be a complex combination of intrinsic bacteria from the respiratory and digestive systems and extrinsic bacteria from soil and the surrounding environment (Carter et al 2007 ;Janaway et al 2009 ). This diverse ecosystem encompasses both aerobic and anaerobic bacteria as well as fungi (Janaway et al 2009 ), whose metabolic pathways degrade proteins, lipids and carbohydrates to produce numerous breakdown products, including VOCs (Boumba et al 2008 ;Dekeirsschieter et al 2009 ;Paczkowski and Schutz 2011 ). This metabolism may be the result of several bacteria or may be products of a sequential food chain with one organism working on the products of the next (Boumba et al 2008 ;Paczkowski and Schutz 2011 ).…”

“…This diverse ecosystem encompasses both aerobic and anaerobic bacteria as well as fungi (Janaway et al 2009 ), whose metabolic pathways degrade proteins, lipids and carbohydrates to produce numerous breakdown products, including VOCs (Boumba et al 2008 ;Dekeirsschieter et al 2009 ;Paczkowski and Schutz 2011 ). This metabolism may be the result of several bacteria or may be products of a sequential food chain with one organism working on the products of the next (Boumba et al 2008 ;Paczkowski and Schutz 2011 ). Microbial modifi cation of VOCs may also occur within soil as compounds migrate from buried remains (Vass et al 2004 ).…”