Fitness to drive and cannabis: Validation of two blood THCCOOH thresholds to distinguish occasional users from heavy smokers

Fabritius, Marie; Augsburger, Marc; Chtioui, Haïthem; Favrat, Bernard; Giroud, Christian

doi:10.1016/j.forsciint.2014.05.014

Cited by 20 publications

(18 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Limited blood and plasma controlledadministration data exist for these compounds (15)(16)(17)35 ). Metabolites provide valuable information on smoking history and time since last intake (34,36 ). No study to date examined phase II metabolites after vaporization and alcohol; these data improve blood and plasma interpretation by toxicologists as medical and recreational cannabis prevalence expands.…”

Section: Continued On Page 866mentioning

confidence: 99%

Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol

et al. 2015

View full text Add to dashboard Cite

BACKGROUND:Increased medical and legal cannabis intake is accompanied by greater use of cannabis vaporization and more cases of driving under the influence of cannabis. Although simultaneous ⌬ 9 -tetrahydrocannabinol (THC) and alcohol use is frequent, potential pharmacokinetic interactions are poorly understood. Here we studied blood and plasma vaporized cannabinoid disposition, with and without simultaneous oral low-dose alcohol.

show abstract

Section: Continued On Page 866mentioning

confidence: 99%

Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Due to its long elimination half-life [11] , THCCOOH accumulates in the blood upon regular cannabis use [12][13][14][15] and has therefore been proposed as diagnostic marker to distinguish between occasional and heavy users [16,17]. In Switzerland, a free THCCOOH blood level of 40 µg/L is currently used as cut-off for the classification of impaired drivers as heavy users, as recommended by Fabritius et al [17,18]. Since chronic cannabis consumption may imply a long-term unfitness to drive, these drivers suspected of heavy cannabis misuse are required to undergo medical assessment of their fitness to drive, even if no active THC was detected in their blood.…”

Section: Introductionmentioning

confidence: 99%

Development of a rapid column-switching LC-MS/MS method for the quantification of THCCOOH and THCCOOH-glucuronide in whole blood for assessing cannabis consumption frequency

et al. 2016

View full text Add to dashboard Cite

The concentration of 11-nor-9-carboxy-Δ 9 -tetrahydrocannabinol (THCCOOH) in whole blood is used as a parameter for assessing the consumption behavior of cannabis consumers. The blood level of THCCOOH-glucuronide might provide additional information about the frequency of cannabis use. To verify this assumption a column-switching liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the rapid and direct quantification of free and glucuronidated THCCOOH in human whole blood was newly developed. The method comprised protein precipitation, followed by injection of the processed sample onto a trapping column and subsequent gradient elution to an analytical column for separation and detection. The total LC run time was 4.5 min. Detection of the analytes was accomplished by electrospray ionization in positive ion mode and selected reaction monitoring using a triple stage quadrupole mass spectrometer. The method was fully validated by evaluating the following parameters: linearity, lower limit of quantification, accuracy and imprecision, selectivity, extraction efficiency, matrix effect, carry-over, dilution integrity, analyte stability and re-injection reproducibility. All acceptance criteria were analyzed and the predefined criteria met. Linearity ranged from 5.0 -500 µg/L for both analytes. The method was successfully applied to whole blood samples from a large collective of cannabis consumers, demonstrating its applicability in the forensic field.

show abstract

“…States with legalized medical or recreational cannabis had increased DUI‐cannabis (DUIC) cases, with enforcement complicated by changing cannabis laws. Blood Δ 9 ‐tetrahydrocannabinol (THC) and its non‐psychoactive metabolite (11‐nor‐9‐carboxy‐THC, THCCOOH) concentrations may provide information regarding time since last intake and cannabis consumption frequency . However, blood collection is invasive and may be delayed 90 min–4 h after a DUI event .…”

Section: Introductionmentioning

confidence: 99%

“…Blood Δ 9 -tetrahydrocannabinol (THC) and its non-psychoactive metabolite (11-nor-9-carboxy-THC, THCCOOH) concentrations may provide information regarding time since last intake and cannabis consumption frequency. [13,14] However, blood collection is invasive and may be delayed 90 min-4 h after a DUI event. [15,16] OF, a valuable alternative sampling matrix, is non-invasively collected, more difficult to adulterate than urine, and provides information about recent intake.…”

Section: Introductionmentioning

confidence: 99%

Controlled vaporized cannabis, with and without alcohol: subjective effects and oral fluid‐blood cannabinoid relationships

Hartman

Brown

Milavetz

et al. 2015

Drug Testing and Analysis

View full text Add to dashboard Cite

Background and Aims Vaporized cannabis and concurrent cannabis and alcohol intake are commonplace. We evaluated cannabis’ subjective effects, with and without alcohol, relative to blood and oral fluid (OF, advantageous for cannabis exposure screening) cannabinoid concentrations and OF/blood and OF/plasma vaporized-cannabinoid relationships. Methods Healthy adult occasional-to-moderate cannabis smokers received vaporized placebo or active cannabis (2.9% and 6.7% Δ9-tetrahydrocannabinol, THC) with or without oral low-dose alcohol (~0.065g/210L peak breath alcohol concentration [BrAC]) in a within-subjects design. Blood and OF were collected up to 8.3h post-dose and subjective effects measured at matched time points with visual-analogue scales and 5-point Likert scales. Linear mixed models evaluated subjective effects by THC concentration, BrAC, and interactions. Effects by time point were evaluated by dose-wise analysis of variance (ANOVA). OF versus blood or plasma cannabinoid ratios and correlations were evaluated in paired-positive specimens. Results Nineteen participants (13 men) completed the study. Blood THC concentration or BrAC significantly associated with subjective effects including “high,” while OF contamination prevented significant OF concentration associations <1.4h post-dose. Subjective effects persisted through 3.3–4.3h, with alcohol potentiating cannabis effects’ duration. Effect-versus-THC concentration and effect-versus-alcohol concentration hystereses were counterclockwise and clockwise, respectively. OF/blood and OF/plasma THC significantly correlated (all Spearman r≥0.71), but variability was high. Conclusions Vaporized cannabis subjective effects were similar to those previously reported after smoking, with duration extended by concurrent alcohol. Cannabis intake was identified by OF testing, but OF concentration variability limited interpretation. Blood THC concentrations were more consistent across subjects and more accurate at predicting cannabis’ subjective effects.

show abstract

Fitness to drive and cannabis: Validation of two blood THCCOOH thresholds to distinguish occasional users from heavy smokers

Cited by 20 publications

References 46 publications

Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol

Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol

Development of a rapid column-switching LC-MS/MS method for the quantification of THCCOOH and THCCOOH-glucuronide in whole blood for assessing cannabis consumption frequency

Controlled vaporized cannabis, with and without alcohol: subjective effects and oral fluid‐blood cannabinoid relationships

Contact Info

Product

Resources

About