The deceased’s sister took the insurance firm to Court to seek pay-outs on two personal accident policies. Our expert was requested to review toxicology reports to provide independent opinions on potential adverse drug interactions, and on the allegedly “elevated” concentrations of four prescribed drugs identified in postmortem blood. Our TFEG expert reported that two drugs (bromazepam and mirtazapine) were actually below toxic levels in living persons, and could not be rightly described as “elevated”. Additionally, based on the findings from a recent Finnish study where duloxetine, mirtazapine and olanzapine were encountered in respectively, 109, 2179 and 1127 of postmortem cases, the concentrations of these three drugs in the deceased’s blood were below the postmortem blood concentrations of fatal poisoning cases. Thus, the levels of the four drugs in the deceased were not excessive, and did not provide evidence of overdose.
“Insurance suit: Man’s death ‘not accident”, The Straits Times (2 Apr 2016).
The Science behind it
Postmortem toxicology has been described as a “toxicological nightmare”, owing to postmortem drug redistribution (“PMR”).8 PMR refers to the processes by which drugs, toxicants and metabolites move between tissues, organs and body fluids after death. This well-known phenomenon, which can significantly change drug concentrations after death, was first reported in the mid-1970s. Large errors and wrong conclusions can arise when postmortem measurements are used to estimate antemortem drug concentrations and the ingested dose.