You probably don't go hunting for decaying bodies too often, but then you probably don’t work in the field of forensics. If you did, then you’d be glad to hear that technology recently developed by America’s National Institute of Standards and Technology (NIST) should make finding buried bodies much easier. Traditionally, cadaver-sniffing dogs have been used to find bodies, but they can be limited in situations such as where a body is buried under concrete. The new device, however, uses a probe slightly thicker than a human hair to probe the soil, detecting ninhydrin-reactive nitrogen (NRN) that collects in air pockets around gravesoil. Previous technology could only achieve that same end through what NIST describes as “the tedious and expensive process” of solvent extraction of soil samples.
The instrument was developed by NIST chemists Thomas J. Bruno and Tara M. Lovestead. Its probe consists of an alumina-coated, porous layer, open tubular column, with a motorized pipette to pull in air samples from the soil at ambient temperature. In the past, soil samples had to be processed at ultra-cold temperatures. The fact that the system utilizes ninhydrin reagent makes it more practical still, as that chemical is already used in law enforcement for exposing latent fingerprints.
The device is the first-ever example of technology that can detect NRN in its vapor phase. In order to probe the soil under a concrete slab for that NRN, a one-eighth inch hole need only be drilled through it.
In the course of their research, the scientists took air samples adjacent to dead feeder rats buried under eight centimeters of soil, laid on top of the soil, and from boxes with no dead rats in them. They took samples at one week intervals for six weeks and then again at 10 and 20 weeks and found that after five weeks, the amount of NRN was at its highest, but was still detectable after 20 weeks.
At present only the probing hardware is portable, but Bruno is working on making the processing end portable too, so the whole system can be used in the field.