Postmortem Cartilage Degradation as a Potential PMI Tool and Preliminary Insights into Associated Soil Microbiome Dynamics

SHAWNA BOLTON

Accurate estimation of the postmortem interval (PMI) remains a persistent challenge in forensic science, particularly in environments where traditional indicators are highly variable. This study investigates postmortem cartilage degradation as a potential complementary tool for PMI estimation, alongside a preliminary exploration of associated changes in the soil microbiome following tissue deposition.

Using pig trotters/limbs as human analogues, controlled decomposition trials were conducted to characterize temporal changes in cartilage tissue across defined PMIs. Histological and structural alterations in the cartilage matrix were assessed to identify measurable degradation patterns that correlate with time since deposition. In parallel, soil samples collected beneath and adjacent to the deposited specimens are being analyzed to examine shifts in microbial community composition associated with decomposition, as well as the potential influence of these microbial communities on cartilage breakdown.

Initial findings indicate progressive, quantifiable changes in cartilage structure with increasing PMI, supporting its potential utility as a time-sensitive forensic marker. Preliminary soil analyses suggest detectable alterations in microbial community profiles following tissue deposition, with evidence of early successional shifts corresponding to decomposition stages. Ongoing sequencing and bioinformatic analyses aim to further characterize these microbial dynamics and evaluate their potential contribution to PMI estimation.

By integrating tissue-based degradation markers with environmental microbial assessments, this research contributes to the development of a multifactorial framework for PMI determination. These findings are particularly relevant to forensic investigations in warm and tropical climates, where accelerated decomposition underscores the need for robust, context-sensitive PMI tools.