Institute of Legal Medicine, University of Frankfurt/Main, Germany.
J Anal Toxicol. 2013 Apr;37(3):152-8. doi: 10.1093/jat/bkt002. Epub 2013 Feb 20.
Oral fluid (OF) tests aid in identifying drivers under the influence of drugs. In this study, 17 heavy cannabis users consumed alcohol to achieve steady blood alcohol concentrations of 0 to 0.7 g/L and smoked cannabis 3 h afterward. OF samples were obtained before and up to 4 h after smoking and on-site tests were performed (Dräger DrugTest 5000 and Securetec DrugWipe 5+). Maximum concentrations of tetrahydrocannabinol (THC) immediately after smoking (up to 44,412 ng/g) were below 4,300 (median 377) ng/g 1 h after smoking and less than 312 (median 88) ng/g 3 h later with 5 of 49 samples negative, suggesting that recent cannabis use might occasionally not be detectable. An influence of alcohol was not observed. Drinking 300 mL variably influenced THC concentrations (median only -29.6%), which suggests that drinking does not markedly affect on-site test performance. Many (92%) Dräger tests performed 4 h after smoking were still positive, indicating sufficient sensitivity for recent cannabis use. Differences in the results of a roadside study with DrugTest 5000 (sensitivity 84.8%, specificity 96.0%, accuracy 84.3%) could be explained by a higher number of true negatives, differences between OF and serum and differences between occasional and chronic users.
唾液（OF）检测有助于识别吸毒的驾驶员。在这项研究中，17 名重度大麻使用者饮酒，使血液酒精浓度稳定在 0 至 0.7 g/L，然后在 3 小时后吸食大麻。在吸烟前和吸烟后 4 小时内采集了 OF 样本，并进行了现场测试（Draeger DrugTest 5000 和 Securetec DrugWipe 5+）。吸烟后即刻（高达 44412 ng/g）的四氢大麻酚（THC）最大浓度（中位数 377 ng/g）在吸烟后 1 小时下降到 312 ng/g（中位数 88 ng/g）以下，5 份样本为阴性，表明最近使用大麻可能偶尔无法检测到。未观察到酒精的影响。饮用 300 毫升的酒精会对 THC 浓度产生影响（中位数仅减少 29.6%），这表明饮酒不会显著影响现场测试的性能。吸烟后 4 小时进行的许多（92%）Draeger 测试仍然呈阳性，表明对最近的大麻使用具有足够的敏感性。与 DrugTest 5000 进行的路边研究结果存在差异（灵敏度 84.8%，特异性 96.0%，准确性 84.3%），这可以用更多的真阴性、OF 和血清之间的差异以及偶尔使用者和慢性使用者之间的差异来解释。
