Fort Worth Police Department, Crime Laboratory, East Lancaster Ave, Fort Worth, TX 3616, United States.
Department of Biomedical and Clinical Sciences, Division of Clinical Chemistry and Pharmacology, University of Linköping, Linköping 58183, Sweden.
J Anal Toxicol. 2024 Jan 31;48(1):9-26. doi: 10.1093/jat/bkad078.
Excessive drinking and drunkenness are underlying factors in many fatal accidents, which make the quantitative determination of ethanol in postmortem (PM) specimens an essential part of all unnatural death investigations. The same analytical methods are used to determine ethanol in blood taken from living and deceased persons although the interpretation of the results is more complicated in medical examiner cases owing to various preanalytical factors. The biggest problem is that under anaerobic conditions ethanol can be produced naturally in decomposed bodies by microbial activity and fermentation of blood glucose. Ways are needed to differentiate antemortem ingestion of ethanol from PM synthesis. One approach involves the determination of ethanol in alternative specimens, such as bile, cerebrospinal fluid, vitreous humor and/or urine, and comparison of results with blood alcohol concentration (BAC). Another approach involves the analysis of various alcohol biomarkers, such as ethyl glucuronide, ethyl sulfate and/or phosphatidylethanol or the urinary metabolites of serotonin 5-hydroxytryptophol/5-hydroxyindoleacetic acid (5-HTOL/5-HIAA). If ethanol had been produced in the body by microbial activity, the blood samples should also contain other low-molecular volatiles, such as acetaldehyde, n-propanol and/or n-butanol. The inclusion of 1-2% w/v sodium or potassium fluoride, as an enzyme inhibitor, in all PM specimens is essential to diminish the risk of ethanol being generated after sampling, such as during shipment and storage prior to analysis. Furthermore, much might be gained if the analytical cut-off for reporting positive BAC was raised from 0.01 to 0.02 g% when PM blood is analyzed. During putrefaction low BACs are more often produced after death than high BACs. Therefore, when the cadaver is obviously decomposed, a pragmatic approach would be to subtract 0.05 g% from the mean analytical result. Any remaining BAC is expected to give a more reliable indication of whether alcohol had been consumed before death.
过度饮酒和醉酒是许多致命事故的潜在因素，这使得定量测定死后（PM）标本中的乙醇成为所有非自然死亡调查的重要组成部分。虽然由于各种分析前因素，在法医案例中对结果的解释更加复杂，但用于确定活体和死者血液中乙醇的分析方法是相同的。最大的问题是，在厌氧条件下，微生物活动和血糖发酵会使分解尸体中自然产生乙醇。需要区分生前摄入的乙醇和 PM 合成物。一种方法是测定替代标本（如胆汁、脑脊液、玻璃体和/或尿液）中的乙醇，并将结果与血液酒精浓度（BAC）进行比较。另一种方法是分析各种酒精生物标志物，如乙基葡萄糖醛酸、乙基硫酸盐和/或磷脂酰乙醇或血清素 5-羟色醇/5-羟吲哚乙酸（5-HTOL/5-HIAA）的尿代谢物。如果乙醇是由微生物活动在体内产生的，那么血液样本中也应该含有其他低分子量挥发物，如乙醛、正丙醇和/或正丁醇。在所有 PM 标本中加入 1-2%w/v 的钠或钾氟化物（作为酶抑制剂）对于减少采样后（如在运输和分析前储存期间）乙醇产生的风险至关重要。此外，如果在分析 PM 血液时将报告阳性 BAC 的分析截止值从 0.01 提高到 0.02g%，可能会有更多收获。在腐败过程中，死后产生的低 BAC 比高 BAC 更为常见。因此，当尸体明显分解时，一种实用的方法是从平均分析结果中减去 0.05g%。任何剩余的 BAC 都有望更可靠地表明在死亡前是否摄入了酒精。
