Shockingly, twenty-year-old human bones can easily be purchased online from websites such as Skulls
Unlimited International (2016) and The Bone Room (2015).
American law enforcement is able to use human flesh that is discarded from hospitals, such as limbs from
amputees, and also from people who have donated their body to science (Salladay, 2004). They also
readily have access to body fluids, blood, teeth and even placenta for dog training purposes (Alexander et
al, 2015). With both countries striving for a common cause- to help find missing people- it is baffling that
the methods used can be at such opposite ends of the spectrum.
In a recent interview with The Telegraph (Evans, 2016), Dr Anna Williams and Lorna Irish criticised the
current method of cadaver dog training, regarding pig substitutes. They have called for a change in the law
to allow hospital patients to voluntarily donate tissue, removed during medical procedures, to a UK
equivalent of the American body farms. Dr Williams has stated that using human tissue would greatly
increase confidence in VR dogs, as well as decrease the negative response this evidence receives in a
criminal court. At the end of this online article, was an interactive poll to ascertain the general public’s
feeling about this; 94% of 373 voters agreed with this plan (Evans, 2016).
Body farms in the USA have been extremely successful, and provided scientists with invaluable knowledge
about the decomposition of the human body; however, these studies cannot be generalised to other parts
of the world because of climate and environmental differences (Hunter et al, 2013; O’Neill, 2015; Williams
and Williams, 2015). Australia has recently become the second country in the world to have a body farm,
which began studies earlier this year when three male cadavers were placed into an on-site grave (O’Neill,
2015; Power, 2016; Sandle, 2016). European research is extremely limited due to the strict regulations,
meaning that data has only been collected from anecdotal experiments with animals and case studies
(Williams and Williams, 2015).
Many experiments have shown that even though anatomically pigs and humans are very similar, they
actually produce different chemicals as they decompose. After death, the cells in the body are deprived of
oxygen, triggering enzymes to begin breaking down the soft tissues, resulting in the production of volatile
organic compounds (VOCs) (Cockle and Bell, 2015; Forbes et al, 2016; Rosier et al, 2015). Vass et al (1997)
stated that aromas are a mixture of potentially hundreds of VOCs, and it has yet to be confirmed which, or
what combination, of these chemicals canines alert to (Forbes et al, 2016; Hoffman et al, 2009;
Oesterhelweg et al, 2008). The ‘lock and key’ theory suggests that each chemical has a different and
unique shape, which must fit with its corresponding site in sensory cells, in the nasal cavity, in order to be
accepted and then sent to the brain for identification (Vass et al, 1997).
Recent studies have aimed to establish human specific indicators through the sampling of VOCs. Vass et al
(2004) buried four human bodies at various depths, and sampled the chemicals that were present at the
soil surface. The study documented a total of 424 specific volatile chemicals released during the
decomposition process. It was noted that putrescine and cadaverine were not detected in this
experiment, however, these chemicals have a low volatility rate and are metabolised by bacteria soon
after release. This was also the case for Rosier et al (2015), who allowed 6 human and 26 animal bodies to
decompose over a six month period and recorded the release of VOCs during this time. One pig carcass
was used, and the results were compared to that of the human VOC profiles. Eight chemicals were
suggested to be both human and pig specific: ethyl pentanoate, propyl butyrate, propyl propionate, ethyl
propionate, 3-methylthio-1-propanol, pyridine, methyl(methylthio)ethyl disulphide and diethyl
disulphide. Rosier et al (2015) also refutes results from Vass (2012), in which he claims that pentane,
decane and undecane are human specific when compared to pig, deer, dog, cat, squirrel and sheep
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