2014/06/27

Scientific American Jun 26, 2014: Changing Smell of Corpses Measures Time of Death

Aromatic chemicals released by dead bodies change at certain times, and this can help forensic scientists and train cadaver sniffing dogs

Not many of us like to consider the complex chemical processes that begin after we die. But new research into the chemical odors released by decomposing bodies is providing forensic scientists with a powerful tool to determine how long a person has been dead, a term known as post-mortem interval (PMI). Understanding this ‘smell of death’ also helps scientists understand how sniffer dogs discover buried disaster victims and locate clandestine graves.

An international research team used two-dimensional gas chromatography time-of-flight mass spectrometry to characterise the odours that create this smell of death:  volatile organic compounds (VOCs).  By measuring the VOCs released from pig carcasses the team identified a cocktail of several different families of molecules, including carboxylic acids, aromatics, sulfurs, alcohols, nitro compounds, as well as aldehydes and ketones. The combination and quantities of these VOCs change as a function of time as a cadaver goes through different stages of decomposition. more