THCCOOH concentrations in whole blood: Are they useful in discriminating occasional from heavy smokers?

Fabritius, Marie; Favrat, Bernard; Chtioui, Haithem; Battistella, Giovanni; Annoni, Jean-Marie; Appenzeller, Monique; Dao, Kim; Fornari, Eleonora; Lauer, Estelle; Mall, Jean-Frédéric; Maeder, Philippe; Mangin, Patrice; Staub, Christian; Giroud, Christian

doi:10.1002/dta.1581

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Journal article

THCCOOH concentrations in whole blood: Are they useful in discriminating occasional from heavy smokers?

Fabritius, Marie CURML University Center of Legal Medicine , UTCF Forensic Toxicology and Chemistry Unit , Lausanne and Geneva, Switzerland
Favrat, Bernard CURML University Center of Legal Medicine , UMPT Unit of Psychology and Traffic Medicine , Lausanne and Geneva, Switzerland
Chtioui, Haithem Division of Clinical Pharmacology and Toxicology, Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland
Battistella, Giovanni Department of Radiology, Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland
Annoni, Jean-Marie Neurology Unit, Department of Medicine, University of Fribourg, Switzerland
Appenzeller, Monique Division of Clinical Pharmacology and Toxicology, Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland
Dao, Kim Division of Clinical Pharmacology and Toxicology, Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland
Fornari, Eleonora Department of Radiology, Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland - CIBM Centre d imagerie BioMédicale , Centre Hospitalier Universitaire Vaudois CHUV unit, Lausanne, Switzerland
Lauer, Estelle CURML University Center of Legal Medicine , UTCF Forensic Toxicology and Chemistry Unit , Lausanne and Geneva, Switzerland
Mall, Jean-Frédéric Department of Psychiatry, SUPAA Service Universitaire de Psychiatrie de l Age Avancé , Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland
Maeder, Philippe Department of Radiology, Centre Hospitalier Universitaire Vaudois CHUV , Lausanne, Switzerland
Mangin, Patrice CURML University Center of Legal Medicine , UTCF Forensic Toxicology and Chemistry Unit , Lausanne and Geneva, Switzerland
Staub, Christian CURML University Center of Legal Medicine , UTCF Forensic Toxicology and Chemistry Unit , Lausanne and Geneva, Switzerland
Giroud, Christian CURML University Center of Legal Medicine , UTCF Forensic Toxicology and Chemistry Unit , Lausanne and Geneva, Switzerland

2014

Published in:

Drug Testing and Analysis. - 2013, vol. 6, no. 1-2, p. 155–163

English Some forensic and clinical circumstances require knowledge of the frequency of drug use. Care of the patient, administrative, and legal consequences will be different if the subject is a regular or an occasional cannabis smoker. To this end, 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) has been proposed as a criterion to help to distinguish between these two groups of users. However, to date this indicator has not been adequately assessed under experimental conditions. We carried out a controlled administration study of smoked cannabis with a placebo. Cannabinoid levels were determined in whole blood using tandem mass spectrometry. Significantly high differences in THCCOOH concentrations were found between the two groups when measured during the screening visit, prior to the smoking session, and throughout the day of the experiment. Receiver operating characteristic (ROC) curves were determined and two threshold criteria were proposed in order to distinguish between these groups: a free THCCOOH concentration below 3 µg/L suggested an occasional consumption (≤ 1 joint/week) while a concentration higher than 40 µg/L corresponded to a heavy use (≥ 10 joints/month). These thresholds were tested and found to be consistent with previously published experimental data. The decision threshold of 40 µg/L could be a cut-off for possible disqualification for driving while under the influence of cannabis. A further medical assessment and follow-up would be necessary for the reissuing of a driving license once abstinence from cannabis has been demonstrated. A THCCOOH level below 3 µg/L would indicate that no medical assessment is required.

Faculty

Faculté des sciences et de médecine

Department

Médecine 3ème année

Language