The formation of adipocere in model aquatic environments

Abstract

An examination of the chemistry of adipocere formation in aquatic systems provides insight into how environmental factors affect the decomposition processes of human remains. Gas chromatography–mass spectrometry (GC-MS) and inductively coupled plasma–mass spectrometry (ICPMS) have been employed to monitor the changes to the chemistry of adipocere formed in aquatic environments used to model seawater, river and chlorinated water systems. Seawater was shown to inhibit adipocere formation, and a distinctively different elemental composition was produced in this environment due to the high concentrations of salts. By comparison, river water has been shown to accelerate the formation of adipocere. Chlorinated water appears to significantly enhance adipocere formation, based on a comparison with established fatty acid concentration values. However, a competing reaction to form chlorohydrins in chlorinated water is believed to be responsible for the unusual findings in this environment. The application of the chemical characterization of adipocere to an understanding of how this particular decomposition product forms in different water environments has been demonstrated, and there is potential to utilise this approach to identify the environment in which a body has been immersed.

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

“…Continued research into the elemental composition of adipocere may aid in further distinguishing adipocere samples into the different stages of formation: early, intermediate and late stage, and may also be useful to differentiate between different water environments in which adipocere has formed. Chemical analysis of the environment in which adipocere forms is also necessary to further understand the variables, such as pH, presence of oxygen, bacteria and water flow, that influence formation 58 . Furthermore, research in the area of adipocere degradation is suggested, especially with focus on the biochemical pathways and environmental influences that govern adipocere formation 42 .…”

“…Saturation of oleic degradation, the point where the rate of degradation did not increase further, was rapid in distilled and slow in saline. 58 found that seawater inhibits adipocere formation, while river water enhances it.…”

“…In this experiment, the chemical characterisation of adipocere was also carried out and showed that only seawater significantly affects its elemental composition. As a result of such findings, the authors suggested that there is a potential to utilise the chemical analysis approach on adipocere, to determine in what type of environment a body has been immersed 58 .…”

Seasonal variation of fatty acid profiles from textiles associated with decomposing pig remains in a temperate Australian environment

“…One means of examining the decomposition process using fatty acid concentrations is to monitor the transformation of unsaturated to saturated fatty acid concentrations that results from hydrogenation reactions. Such an approach has been used to monitor the formation of the decomposition product adipocere, which is comprised of a mixture of fatty acids [6,14]. Earlier investigations divided the process of adipocere formation into three stages based on the amount of saturated fatty acids present and the % of saturated fatty acids at each stage has been estimated as early (40-60%), intermediate (70-90%) and advanced (>90%).…”

Determination of Postmortem Interval by Estimating CSF Proteins Concentration after Death, by Dye Binding Method at a Tertiary Care Hospital in Lahore, Pakistan

“…These processes occur at different intervals. 9 No doubt, these methods depict changes and these changes are correlated with PMI, but multiple researches have shown that these physical changes get influenced by climatic changes, age of deceased, and any underlying disease. 10 Therefore, lack of precision of physical methods led to introduction of biochemical methods.…”