``Not everything that can be counted counts'' in ethanol toxicological results: an antemortem and postmortem technical interpretation focusing on driving under the influence

Data de publicação: 12/07/2024 Data Ahead of Print: 01/07/2024

Unidades de investigação

• Ciências da Saúde Pública e Forenses, e Educação Médica

Abstract

Ethanol blood analysis is the most common request in forensic toxicology, and some studies point to positive results in approximately one-third of all unnatural deaths. However, distinguishing sober deaths from drunk deaths is not as simple as it may seem. This technical, clinical, and forensic interpretation is proposed to interpret the ethanol toxicological results, discussing several artefacts and pitfalls that must be considered, namely focusing on driving under the influence. This work is presented with a practical and objective approach, aiming to alleviate the complexities associated with clinical, physiological, pathophysiological, and toxicological aspects to enhance comprehension, practicality, and applicability of its content, especially to courts. Particularly the physical integrity of the body, the postmortem interval, putrefactive signs, anatomic place of blood collection, alternative samples such as vitreous humour and urine, the possibility of postmortem redistribution, the inclusion of preservatives in containers, and optimal temperature conditions of shipment are among some of the aspects to pay attention. Although several biomarkers related to postmortem microbial ethanol production have been proposed, their translation into forensic routine is slow to be implemented due to the uncertainties of their application and analytical difficulties. Specifically, in the interpretation of ethanol toxicological results, ``not everything that can be counted counts and not everything that counts can be counted'' (attributed to Albert Einstein).

Keywords

• ethanol; alcohol; postmortem diffusion; endogenous; putrefaction; blood; urine; vitreous humour; interpretation; biomarkers