Abstract

The advantages of analysis of drugs in hair samples are recognized for the long window of detection, alongside easy sampling and long stability after sample collection. Alcohol markers, ethyl glucuronide (EtG) and total fatty acid ethyl esters (FAEEs) in hair, are widely used for monitoring alcohol consumption for clinical and forensic purposes. Although stability of drugs and EtG in hair samples is documented to a certain extent, stability of FAEEs in hair samples after collection has not been reported. This study covered hair samples that had been tested for FAEEs on the day of arrival at the laboratory and retested between 4 and 80 months later. The statistical analysis of the data set reveals significant lower FAEEs levels including ethyl palmitate (EtPa) ester levels when samples were retested for the second time after 6 days of storage under ideal conditions. Specifically, the results suggest that when measuring total FAEEs or solely EtPa in hair samples, the elapsed time between sample collection and analysis of the sample needs to be considered when interpreting the results. The recommendation is that whenever hair samples need to be tested for total FAEEs or EtPa, the analytical procedure needs to be performed within 1 week after collection in order to obtain meaningful results. The study results substantiate the case for the use of hair samples solely for the analysis of EtG, in conjunction with other measurements such as full blood count, carbohydrate-deficient transferrin test, liver function test or phosphatidylethanol alongside clinical assessment for a more effective evaluation of alcohol consumption.

中文翻译：

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延长储存时间对头发样品中脂肪酸乙酯稳定性的影响

摘要

毛发样品中药物分析的优势在于检测窗口长，易于采样和样品收集后的长期稳定性。头发中的酒精标记，乙基葡糖醛酸苷（EtG）和总脂肪酸乙酯（FAEEs）被广泛用于监测酒精消耗，以用于临床和法医目的。尽管在一定程度上记载了药物和EtG在头发样品中的稳定性，但尚未报道收集后FAEE在头发样品中的稳定性。这项研究涵盖了在到达实验室当天已对FAEE进行测试并在4到80个月后重新测试的头发样本。数据集的统计分析表明，在理想条件下储存6天后第二次重新测试样品时，包括棕榈酸乙酯（EtPa）酯在内的FAEEs水平明显降低。具体而言，结果表明，在测量头发样品中的总FAEE或仅测量EtPa时，在解释结果时需要考虑样品收集与样品分析之间的经过时间。建议是，每当需要对头发样本中的总FAEE或EtPa进行测试时，都需要在采集后1周内进行分析程序，以获得有意义的结果。研究结果证实了将头发样本仅用于EtG分析以及其他测量（例如全血细胞计数，缺乏碳水化合物的转铁蛋白测试，