Evidence of adipocere in a burial pit from the foot and mouth epidemic of 1967 using gas chromatography–mass spectrometry

A practical review of adipocere: Key findings, case studies and operational considerations from crime scene to autopsy

After death, the body begins decomposition, a process that starts with the breakdown of organic matter and typically leads to the complete degradation of a body. Such a process is highly affected by (micro and macro) environmental factors of intrinsic and extrinsic nature. Adipocere is a substance formed from the decomposition of adipose tissue and represents a disruption to the typical decomposition process. Such disruption causes decomposition to slow or arrest completely, placing a body into a state of preservation, and determines complications in the estimation of the time since death (Post-Mortem Interval, PMI). While several studies have been performed on the nature, the formation and the degradation of adipocere, there is still no reliable model to assess the PMI of a body exhibiting it. Case studies are an important source to aid pathologists and investigators during a case. This review presents a summary and an update on the knowledge surrounding the chemistry and the factors affecting adipocere formation and degradation, the timing and the distribution of adipocere throughout a body, and the techniques used to investigate it. Furthermore, a table of the most important case studies involving adipocere since 1950, several images and descriptions of recent cases and operational considerations for the best practice at the crime scene and autopsy are presented to be used as a reference to facilitate forensic professionals in adipocere cases.

Preservation of cell structures in a medieval infant brain: a paleohistological, paleogenetic, radiological and physico-chemical study

Cerebral tissues from archaeological human remains are extremely rare findings. Hereby, we report a multidisciplinary study of a unique case of a left cerebral hemisphere from a 13th century AD child, found in north-western France. The cerebral tissue-reduced by ca. 80% of its original weight-had been fixed in formalin since its discovery. However, it fully retained its gross anatomical characteristics such as sulci, and gyri; the frontal, temporal and occipital lobe as well as grey and white matter could be readily recognised. Neuronal remains near the hippocampus area and Nissl bodies from the motor cortex area were observed (Nissl, Klüver-Barrera staining). Also, computed tomography (CT) and magnetic resonance imaging (T1, proton density, ultra short echo time sequences) were feasible. They produced high quality morpho-diagnostic images. Both histological and radiological examinations could not confirm the pathologist's previously suggested diagnosis of cerebral haemorrhage as the cause of death. Reproducible cloned mtDNA sequences were recovered from the skeleton but not from the brain itself. This was most likely due to the combined effect of formaldehyde driven DNA-DNA and/or DNA-protein cross-linking, plus hydrolytic fragmentation of the DNA. The chemical profile of the brain tissue, from gas-chromatography/mass-spectroscopy analysis, suggested adipocerous formation as the main aetiology of the mummification process. The hereby presented child brain is a unique paleo-case of well-preserved neuronal cellular tissue, which is a conditio sine qua non for any subsequent study addressing wider perspectives in neuroscience research, such as the evolution of brain morphology and pathology.

Modelling the buried human body environment in upland climes using three contrasting field sites

Despite an increasing literature on the decomposition of human remains, whether buried or exposed, it is important to recognise the role of specific microenvironments which can either trigger or delay the rate of decomposition. Recent casework in Northern England involving buried and partially buried human remains has demonstrated a need for a more detailed understanding of the effect of contrasting site conditions on cadaver decomposition and on the microenvironment created within the grave itself. Pigs (Sus scrofa) were used as body analogues in three inter-related taphonomy experiments to examine differential decomposition of buried human remains. They were buried at three contrasting field sites (pasture, moorland, and deciduous woodland) within a 15 km radius of the University of Bradford, West Yorkshire, UK. Changes to the buried body and the effect of these changes on hair and associated death-scene textile materials were monitored as was the microenvironment of the grave. At recovery, 6, 12 and 24 months post-burial, the extent of soft tissue decomposition was recorded and samples of fat and soil were collected for gas chromatography mass spectrometry (GCMS) analysis. The results of these studies demonstrated that (1) soil conditions at these three burial sites has a marked effect on the condition of the buried body but even within a single site variation can occur; (2) the process of soft tissue decomposition modifies the localised burial microenvironment in terms of microbiological load, pH, moisture and changes in redox status. These observations have widespread application for the investigation of clandestine burial and time since deposition, and in understanding changes within the burial microenvironment that may impact on biomaterials such as hair and other associated death scene materials.