Effects of the environment on bone mass: A human taphonomic study Yann Delannoy a,b,c,⇑ , Thomas Colard a,b , Erwan Le Garff a,b , Vadim Mesli a,b , Cindy Aubernon a , Guillaume Penel b,c , Valéry Hedouin a,b , Didier Gosset a,b a EA 7367 Forensic Taphonomy Unit – Lille Forensic Institute, Université de Lille, F-59000 Lille, France b Centre Hospitalier Régional Universitaire de Lille, F-59000 Lille, France c EA 4490 Physiopathologie des maladies osseuses inflammatoires, Université de Lille, F-59000 Lille, France article info Article history: Received 24 November 2015 Received in revised form 18 April 2016 Accepted 19 April 2016 Available online 20 April 2016 Keywords: Forensic science Forensic anthropology Burial Postmortem interval Bone moisture Desiccation abstract An experiment was designed using human ribs placed in different environments to document how mois- ture and temperature affect the bone mass according to the postmortem interval. The bones were defleshed, weighed and partially buried, with some ribs being left unburied as controls. The ribs were weighed daily, and the mass loss was monitored over a period of 90 days. The results showed that signif- icant differences in bone mass loss exist between environments, where the bone mass loss was signifi- cantly faster in an environment with low moisture content. This mass loss is thought to be primarily associated with the desiccation of the body and then for a greater part, with the atmospheric moisture content. However, the loss of bone mass can also be explained by early alterations in the organo- mineral matrix which were highlighted by Raman spectroscopy method. Ó 2016 Elsevier Ireland Ltd. All rights reserved. The diagenesis of human remains is subject to many variables. These variables are extrinsic, i.e., related to the environment where the body is located, or intrinsic, i.e., related to the body itself. From an ecological perspective, a cadaver is an organic resource that will interact with its environment [1]. Gravesoil chemistry techniques are therefore essential because the type of soil will impact the decomposition process [2,3]. When skeletonized remains are dis- covered outside, extrinsic factors are of major importance, and a detailed analysis of the environment (moisture, pH, temperature, activity of scavengers, etc.) is crucial for estimating the post- mortem interval (PMI) [4–7]. The effects of temperature and moisture have been described in previous studies. The relationship between temperature and cada- ver decomposition is mainly due to the development of entomo- logical activity on decomposing bodies because the majority of bodies found are at the soil surface [8]. The impact of moisture (and the microorganisms associated with it [9]) on the decompos- ing corpse has classically been described for buried bodies (with soft tissue present): a low moisture content promotes desiccation, whereas in high moisture settings, the breakdown is slower and is associated with the formation of adipocere [5–7]. In this study, we used defleshed human bones to assess the impact of different envi- ronments (i.e., these extrinsic parameters) and the length of time after death. The current techniques used to determine the PMI for skele- tonized remains are based on methods related to the physical or chemical reactivity between the bone and substrates [10–12], physico-chemical analyses of the bone composition [13–16] or radioisotope measurements [17–20]. These are often difficult to interpret and can provide complex results that are difficult to exploit in a forensic context. However, above all, these techniques can be very expensive and difficult to use in daily practice. To over- come these difficulties, the use of macroscopic methods to deter- mine a PMI for skeletonized remains, especially those with a simple design and a non-destructive nature, would be valuable [21]. The macroscopic factors that are studied include the change of the bone texture, its color, the number and size of cracks and its mass. Our current study focuses on the changes in bone mass over time because the variation of the bone mass loss in the post- mortem period can provide information about bone diagenesis. The results of this study will not only provide a quantitative under- standing of bone diagenesis progress but will also provide informa- tion about the early physico-chemical alterations of bones [4,22]. Bone is indeed an organo-mineral composite and during its diage- nesis, each component undergoes changes. The organic phase, which represents about 20% of bone structure, is mainly composed of type I collagen, while mineral phase is composed with hydrox- yapatite crystals. In order to study these early organo-mineral http://dx.doi.org/10.1016/j.legalmed.2016.04.006 1344-6223/Ó 2016 Elsevier Ireland Ltd. All rights reserved. ⇑ Corresponding author at: Institut de Médecine Légale – CHRU de Lille, rue André Verhaeghe, 59037 Lille Cedex, France. E-mail address: yann.delannoy@univ-lille2.fr (Y. Delannoy). Legal Medicine 20 (2016) 61–67 Contents lists available at ScienceDirect Legal Medicine journal homepage: www.elsevier.com/locate/legalmed