title: Detection of decomposition volatile organic compounds in soil following removal of remains from a surface deposition site.
abstract: OBJECTIVE
  Cadaver-detection dogs use volatile organic compounds (VOCs) to search for human remains including those deposited on or beneath soil. Soil can act as a sink for VOCs, causing loading of decomposition VOCs in the soil following soft tissue decomposition. The objective of this study was to chemically profile decomposition VOCs from surface decomposition sites after remains were removed from their primary location.
  
  
  METHODS
  Pig carcasses were used as human analogues and were deposited on a soil surface to decompose for 3 months. The remains were then removed from each site and VOCs were collected from the soil for 7 months thereafter and analyzed by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry (GC×GC-TOFMS).
  
  
  RESULTS
  Decomposition VOCs diminished within 6 weeks and hydrocarbons were the most persistent compound class. Decomposition VOCs could still be detected in the soil after 7 months using Principal Component Analysis.
  
  
  CONCLUSIONS
  This study demonstrated that the decomposition VOC profile, while detectable by GC×GC-TOFMS in the soil, was considerably reduced and altered in composition upon removal of remains. Chemical reference data is provided by this study for future investigations of canine alert behavior in scenarios involving scattered or scavenged remains.
authors.affiliation: Centre for Forensic Science, University of Technology Sydney (UTS), PO Box 123, Broadway, NSW, 2007, Australia, katelynn.perrault@uts.edu.au.
authors.forename: Katelynn A
authors.initials: KA
authors.lastname: Perrault
authors.forename: Pierre-Hugues
authors.initials: PH
authors.lastname: Stefanuto
authors.forename: Barbara H
authors.initials: BH
authors.lastname: Stuart
authors.forename: Tapan
authors.initials: T
authors.lastname: Rai
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Focant
authors.forename: Shari L
authors.initials: SL
authors.lastname: Forbes
mesh_terms: D000818:Animals; D008401:Gas Chromatography-Mass Spectrometry; D023421:Models, Animal; D011180:Postmortem Changes; D025341:Principal Component Analysis; D012987:Soil / Q000737:chemistry*; D013552:Swine; D055549:Volatile Organic Compounds / Q000032:analysis*
chemical_list: D012987:Soil; D055549:Volatile Organic Compounds