External contamination of hair by cannabis smoking requires a careful evaluation in forensic toxicology. Medical and recreational cannabis are increasingly consumed by e-cigarettes, which give rise to side-stream vapor. Moreover, products containing low Δ9-tetrahydrocannabinol (Δ9-THC) and rich in cannabidiol (CBD) started spreading legally. The goal of the present study was to assess whether hair analysis could allow to distinguish the type of delivered product, with low or high Δ9-THC, and the delivering mode, by smoking or vaping. Contamination of blank hair was mimicked by in vitro exposure to low- (0.4%) and high-Δ9-THC (9.7%) products delivered by smoking and vaping within a small confined system. Cannabis vaping extracts were prepared to deliver identical target Δ9-THC doses. Eighty samples were analyzed by ultrahigh-performance liquid chromatography mass spectrometry and quantified for Δ9-THC and CBD. After contamination by cannabis smoking, THC levels were in line with past in vitro and in vivo studies. Samples exposed to cannabis (169.30 ng/mg) showed significantly higher Δ9-THC than hair exposed to “light cannabis” (35.54 ng/mg), and the opposite was seen for the CBD/Δ9-THC ratio. Hair contaminated by vaping or smoking did not show a statistically different Δ9-THC content.

中文翻译：

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大麻和吸烟和电子烟带来的“淡大麻”对头发的外部污染：一项体外研究

吸食大麻对头发的外部污染需要法医毒理学的仔细评估。电子烟越来越多地消耗医用和娱乐大麻，从而产生侧流蒸汽。此外，含有低Δ9-四氢大麻酚（Δ9-THC）和富含大麻二酚（CBD）的产品开始合法传播。本研究的目的是评估头发分析是否可以区分所输送产品的类型（Δ9-THC 低或高）以及输送模式（吸烟或电子烟）。通过在小型密闭系统内吸烟和电子烟产生的低（0.4％）和高Δ9-THC（9.7％）产品的体外暴露来模拟空白头发的污染。大麻电子烟提取物的制备可提供相同的目标 Δ9-THC 剂量。通过超高效液相色谱质谱法分析了 80 个样品，并对 Δ9-THC 和 CBD 进行了定量。受到吸食大麻污染后，THC 水平与过去的体外和体内研究一致。暴露于大麻的样本（169.30 ng/mg）显示出的 Δ9-THC 显着高于暴露于“淡大麻”（35.54 ng/mg）的头发，而 CBD/Δ9-THC 比率则相反。被电子烟或吸烟污染的头发没有表现出统计学上不同的 Δ9-THC 含量。