Science Daily is hard boiled. As hard boiled as death. And death, they say, has a smell all its own:
Speaking at the 238th National Meeting of the American Chemical Society (ACS), they said a profile of the chemicals released from decomposing bodies could also lead to a valuable new addition to the forensic toolkit: An electronic device that could determine the time elapsed since death quickly, accurately and onsite.
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Decomposing bodies release more than 30 compounds. Some, like the aptly-named “putrescine” and “cadaverine,” develop early in the decomposition process. Past studies used donated human bodies that were two to three days old. As a result, these studies were unable to detect putrescine, cadaverine, and other compounds that appear very early in the decomposition process.
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Sykes and Jones placed dead pigs in specially designed odor-collecting units under a variety of environmental conditions. Above each specimen, they affixed special sensors known as solid phase micro extraction (SPME) fibers to capture the gases. These specially-coated fibers are widely used to sample chemical composition of air. Jones and Sykes collected odor data every six to 12 hours over the course of a week.