I thought I’d ease my way into the conference in as macabre a way as possible — with the smell of decaying flesh.

Grad student Sarah Jones and her advisor Dan Sykes at Pennsylvania State University presented their work on the volatile chemicals that waft from dead pigs’ bodies during the earliest stages of decay. The idea is to determine the chemical profiles of a body’s aroma at different time points after death, which might help crime scene investigator-types accurately determine the time of death.

Jones kicked off the show with some gnarly descriptions of the various stages of decomposition, starting with “fresh” and ending with “dry decay”, during with the bones finally turn to dust, as it were. My personal favorite was called the “black putrefaction” stage, at which point the body cavity — bloated from the gases and fluids produced by invading bacteria — ruptures, transforming the carcass into a wide open rotting flesh-fest for hungry insects and microbial scavengers. I should note that during Jones’s descriptions, a smiling Sykes held up large color images of decaying pigs in each respective stage.

These different stages of decay are very well studied — people even know which insects invade which orifices at which timepoints. Decaying flesh is the focus of America’s fascinating “body farms”, where universities in Tennessee, Texas and North Carolina recognize the scientific merits of having dead human bodies rotting away on their campuses.

But although people know all the gory visual details of decomposition, they’re less certain about the smell. This would be helpful, says Jones, for developing a portable electronic device that could determine time of death on-site and in a quick and accurate way.

The researchers set up freshly-dead pigs in special smell-catching death chambers. They used pigs because they’re about the same size as humans, rot in a similar fashion and can be studied immediately after death — no need to politely pause for mourning family members.

The chambers are outfitted with solid phase microextraction (SPME) fibers, which catch the volatile organic compounds. Jones and Sykes say the use of these fibers is the biggest advancement of their work, as previous studies of death smells used sorbent tubes, which are bulky and inconvenient, meaning they can’t be used “in the field”.

Jones didn’t really go into the details of the chemical profile, though it included names like “putrescine” and “cadaverine” and the more subtle “indole precursors”. So far, the research hasn’t turned up any big surprises, but the SPME fibers will let them go out into the field to check volatiles in different environmental conditions, which may turn up some new scents. Jones also repeatedly insisted that the work is in its “very very early stages”.

Image: FBI.gov

I thought I’d ease my way into the conference in as macabre a way as possible — with the smell of decaying flesh.

Grad student Sarah Jones and her advisor Dan Sykes at Pennsylvania State University presented their work on the volatile chemicals that waft from dead pigs’ bodies during the earliest stages of decay. The idea is to determine the chemical profiles of a body’s aroma at different time points after death, which might help crime scene investigator-types accurately determine the time of death.

Jones kicked off the show with some gnarly descriptions of the various stages of decomposition, starting with “fresh” and ending with “dry decay”, during with the bones finally turn to dust, as it were. My personal favorite was called the “black putrefaction” stage, at which point the body cavity — bloated from the gases and fluids produced by invading bacteria — ruptures, transforming the carcass into a wide open rotting flesh-fest for hungry insects and microbial scavengers. I should note that during Jones’s descriptions, a smiling Sykes held up large color images of decaying pigs in each respective stage.

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