X-Pertise Consulting, 42 rue Principale, Mittelhausbergen, France.
Institut de Médecine Légale, 11 rue Humann, Strasbourg, France.
J Anal Toxicol. 2020 Jan 7;44(1):65-68. doi: 10.1093/jat/bkz004.
The retrospective calendar of an individual's drug use requires a multisectional analysis in which the length of hair, corresponding to the full temporal window available, is cut into shorter sections to measure drug use during shorter periods of time (generally 1 cm corresponds to ~1 month). Segmental hair analysis is used to verify both previous drug history and recent enforced abstinence. However, after drug discontinuation, the fresh new hair growth segment cannot be immediately negative, due to the contribution of dormant hair. The objective of the study was to test hair samples from chronic tramadol and cannabis users after the discontinuation of both drugs and to evaluate the delay to wait until the hair will become negative. Hair specimens were obtained from eight subjects with a known history of tramadol abuse. Hair was collected 3-6 months after tramadol discontinuation. Tramadol was tested by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with a LOQ at 5 pg/mg. A second set of hair specimens were obtained from 15 subjects with a known history of cannabis abuse. Hair was collected 6-9 months after cannabis discontinuation. THC-COOH was tested by LC-MS-MS with a LOQ at 0.2 pg/mg. The hair stands were cut into L × 1 cm segments, according to their length (L), and tested for the respective drug. It was asked to each subject to clearly indicate the date of drug discontinuation. Assuming a rate of hair growth of 1 cm/month, the segment corresponding to the time of last drug use was calculated. The older segment just before this one was considered as the 100% of the response. THC-COOH and tramadol concentrations in this segment ranged from 2.3 to 8.9 and 895 to 21,010 pg/mg, respectively. After cessation of drug consumption, the presence of both drugs in new growing hair segments continued for a certain period with a more or less broad transition zone. Negative hair results were obtained ~3-4 and 6-7 months after cessation of tramadol and cannabis abuse.
个体药物使用的回顾性日历需要进行多节段分析，其中，头发的长度（对应于可用的完整时间窗口）被切成更短的节段，以测量较短时间内的药物使用情况（通常 1 厘米对应约 1 个月）。分段头发分析用于验证既往药物史和近期强制戒断。然而，在停止药物使用后，由于休眠头发的贡献，新长出的头发段不能立即呈阴性。该研究的目的是测试停用曲马多和大麻的慢性使用者的头发样本，并评估等待头发呈阴性所需的时间延迟。从已知滥用曲马多的 8 名受试者中获得头发样本。在停用曲马多 3-6 个月后采集头发。通过液相色谱-串联质谱（LC-MS-MS）检测曲马多，定量限为 5 pg/mg。从已知滥用大麻的 15 名受试者中获得第二组头发样本。在停用大麻 6-9 个月后采集头发。通过 LC-MS-MS 检测 THC-COOH，定量限为 0.2 pg/mg。根据头发的长度（L），将头发切成 L×1 cm 的节段，并对相应的药物进行检测。要求每位受试者清楚地标明药物停用的日期。假设头发每月生长 1 厘米，计算出最后一次使用药物的时间段对应的节段。前一个稍老的节段被认为是 100%的反应。该节段中 THC-COOH 和曲马多的浓度分别为 2.3 至 8.9 和 895 至 21010 pg/mg。停止药物使用后，两种药物在新生长的头发段中仍存在一定时间，具有或多或少宽的过渡区。停用曲马多和大麻滥用后约 3-4 个月和 6-7 个月，头发结果呈阴性。
