RCU Labs, Inc., 408 Sunrise Avenue, Roseville, CA, 95661-4123, USA.
Cancer Immunotherapy Research Institute, 408 Sunrise Avenue, Roseville, CA, 95661, USA.
Sci Rep. 2022 May 18;12(1):8323. doi: 10.1038/s41598-022-11481-5.
Previous investigators have found no clear relationship between specific blood concentrations of ∆-tetrahydrocannabinol (∆-THC) and impairment, and thus no scientific justification for use of legal "per se" ∆-THC blood concentration limits. Analyzing blood from 30 subjects showed ∆-THC concentrations that exceeded 5 ng/mL in 16 of the 30 subjects following a 12-h period of abstinence in the absence of any impairment. In blood and exhaled breath samples collected from a group of 34 subjects at baseline prior to smoking, increasing breath ∆-THC levels were correlated with increasing blood levels (P < 0.0001) in the absence of impairment, suggesting that single measurements of ∆-THC in breath, as in blood, are not related to impairment. When post-smoking duration of impairment was compared to baseline ∆-THC blood concentrations, subjects with the highest baseline ∆-THC levels tended to have the shortest duration of impairment. It was further shown that subjects with the shortest duration of impairment also had the lowest incidence of horizontal gaze nystagmus at 3 h post-smoking compared to subjects with the longest duration of impairment (P < 0.05). Finally, analysis of breath samples from a group of 44 subjects revealed the presence of transient cannabinoids such as cannabigerol, cannabichromene, and ∆-tetrahydrocannabivarin during the peak impairment window, suggesting that these compounds may be key indicators of recent cannabis use through inhalation. In conclusion, these results provide further evidence that single measurements of ∆-THC in blood, and now in exhaled breath, do not correlate with impairment following inhalation, and that other cannabinoids may be key indicators of recent cannabis inhalation.
先前的研究人员并未发现 ∆-四氢大麻酚 (∆-THC) 的特定血液浓度与损伤之间存在明确关系，因此没有科学依据支持使用合法的“纯 ∆-THC”血液浓度限制。分析 30 名受试者的血液样本显示，在 12 小时的戒断期内，30 名受试者中有 16 名的 ∆-THC 浓度超过 5ng/mL，但并未出现任何损伤。在一组 34 名受试者在吸烟前的基线时采集的血液和呼气样本中，呼气中 ∆-THC 水平的增加与血液水平的增加呈正相关（P < 0.0001），且没有出现损伤，这表明呼气中 ∆-THC 的单一测量，就像血液中一样，与损伤无关。当将吸烟后损伤持续时间与基线时的 ∆-THC 血液浓度进行比较时，基线时 ∆-THC 水平最高的受试者的损伤持续时间往往最短。进一步表明，与损伤持续时间最长的受试者相比，损伤持续时间最短的受试者在吸烟后 3 小时的水平性眼球震颤发生率也最低（P < 0.05）。最后，对一组 44 名受试者的呼气样本进行分析发现，在峰值损伤窗口期间存在瞬态大麻素，如大麻二醇、大麻色烯和 ∆-四氢大麻素，这表明这些化合物可能是通过吸入最近使用大麻的关键指标。总之，这些结果进一步证明，血液中 ∆-THC 的单次测量值，现在包括呼气中的 ∆-THC 测量值，与吸入后损伤不相关，而其他大麻素可能是最近吸入大麻的关键指标。
