Effect of Blood Collection Time on Measured Δ9-Tetrahydrocannabinol Concentrations: Implications for Driving Interpretation and Drug Policy

Hartman, Rebecca L.; Brown, Timothy L.; Milavetz, Gary; Spurgin, Andrew; Gorelick, David A.; Gaffney, Gary R.; Huestis, Marilyn A.

doi:10.1373/clinchem.2015.248492

Cited by 51 publications

(34 citation statements)

References 31 publications

(42 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A clear consensus among different US states on the permissible THC concentration is lacking; however, 5 ng mL −1 is commonly reported as the cutoff limit [30]. Also, estimating the time of last use of cannabis in user is complicated due to polymorphic differences and different metabolism in frequent versus non-frequent users.…”

Section: Discussionmentioning

confidence: 99%

Ultra-high performance liquid chromatography tandem mass-spectrometry for simple and simultaneous quantification of cannabinoids

Jamwal

Topletz

Ramratnam

et al. 2017

Journal of Chromatography B

View full text Add to dashboard Cite

Cannabis is used widely in the United States, both recreationally and for medical purposes. Current methods for analysis of cannabinoids in human biological specimens rely on complex extraction process and lengthy analysis time. We established a rapid and simple assay for quantification of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), 11-hydroxy Δ9-tetrahydrocannabinol (11-OH THC) and 11-nor-9-carboxy-Δ9-tetrahydrocannbinol (THC-COOH) in human plasma by U-HPLC-MS/MS using Δ9-tetrahydrocannabinol-D3 as the internal standard. Chromatographic separation was achieved on an Acquity BEH C18 column using a gradient comprising of water (0.1% formic acid) and methanol (0.1% formic acid) over a 6 min run-time. Analytes from 200 µL plasma were extracted using acetonitrile (containing 1% formic acid and THC-D3). Mass spectrometry was performed in positive ionization mode, and total ion chromatogram was used for quantification of analytes. The assay was validated according to guidelines set forth by Food and Drug Administration of United States. An eight-point calibration curve was fitted with quadratic regression (r2>0.99) from 1.56 to 100 ng mL−1 and a lower limit of quantification (LLOQ) of 1.56 ng mL−1 was achieved. Accuracy and precision calculated from six calibration curves was between 85 to 115% while the mean extraction recovery was >90% for all the analytes. Several plasma phospholipids eluted after the analytes thus did not interfere with the assay. Bench-top, freeze-thaw, auto-sampler and short-term stability ranged from 92.7 to 106.8% of nominal values. Application of the method was evaluated by quantification of analytes in human plasma from six subjects.

show abstract

Section: Discussionmentioning

confidence: 99%

Ultra-high performance liquid chromatography tandem mass-spectrometry for simple and simultaneous quantification of cannabinoids

Jamwal

Topletz

Ramratnam

et al. 2017

Journal of Chromatography B

View full text Add to dashboard Cite

show abstract

“…It is possible, for example, to utilize hair samples that will provide an index of use over 3–5 months and also provide a basic ratio of THC and CBD (Demirakca et al, 2011). As toxicology tests of urine and other bodily fluids continue to improve (Hartman et al, 2015, 2016), researchers will need to update current methods and incorporate additional techniques to address some of these fundamental questions of pharmacokinetics and pharmacodynamics of marijuana.…”

Section: Remaining Questions and Future Directionsmentioning

confidence: 99%

Effects of Marijuana Use on Brain Structure and Function

Brumback

Castro

Jacobus

et al. 2016

International Review of Neurobiology

View full text Add to dashboard Cite

Marijuana, behind only tobacco and alcohol, is the most popular recreational drug in America with prevalence rates of use rising over the past decade. A wide range of research has highlighted neurocognitive deficits associated with marijuana use, particularly when initiated during childhood or adolescence. Neuroimaging, describing alterations to brain structure and function, has begun to provide a picture of possible mechanisms associated with the deleterious effects of marijuana use. This chapter provides a neurodevelopmental framework from which recent data on brain structural and functional abnormalities associated with marijuana use is reviewed. Based on the current data, we provide aims for future studies to more clearly delineate the effects of marijuana on the developing brain and to define underlying mechanisms of the potential long-term negative consequences of marijuana use.

show abstract

“…Cannabis‐alcohol effects were additive rather than synergistic, with 5 μg/L THC + 0.5 g/L alcohol showing similar SDLP to 0.8 g/L alcohol alone (Hartman et al, ). During‐drive THC concentrations previously associated with impairment (≥8.2 μg/L) decreased to median < 5 μg/L by 3.3 hr post dose and < 2 μg/L by 4.8 hr post dose; only 1 participant had THC ≥5 μg/L after 3.3 hr (Hartman et al, ).…”

Section: Risks Of Driving Under the Influence Of Drugsmentioning

confidence: 98%

Driving under the influence of drugs

Marillier

Verstraete

2019

WIREs Forensic Science

View full text Add to dashboard Cite

Driving is a very complex task, requiring the cooperation of several different cognitive and psychomotor functions at once. Approximately 2% of the drivers drive under the influence of drugs, sometimes more (20%) and more at specific times (weekend nights). Population surveys show that self‐reported driving after using psychoactive drugs (mostly cannabis) varies between 3.8 and 29.9%. In injured and fatally injured drivers, about 20–40% test positive for drugs. The risk of a crash is almost doubled after cannabis use, increased about seven times after amphetamine use. For the other drugs, the risk falls between these extremes. Amphetamines are estimated to cause half of the fatalities due to driving under the infuence of drugs (DUID). Medicinal drugs, taken according to prescription, only increase crash risk by 20–40%. In France 4% and 3% of the accidents could be prevented if no one drove after taking cannabis and impairing therapeutic drugs, respectively. Three types of DUID legislation exist: “impairment” legislation, “per se” legislation and the “two‐tier” approach that combines both. In impairment legislation, the prosecution must demonstrate that the driver was impaired or “under the influence.” A “per se” law prohibits driving if drugs are present in blood, serum, plasma, or oral fluid (OF) above a certain threshold concentration. OF is commonly used for roadside drug screening of drivers, and increasingly for confirmation as well. Recently developed methods for confirmation analysis, either on blood or on OF, use liquid chromatography (tandem) mass spectrometry (LC–MS[MS]) to test for dozens of drugs on a small sample volume. This article is categorized under: Toxicology > Drug‐Impaired Driving Toxicology > Drug Analysis

show abstract

Effect of Blood Collection Time on Measured Δ9-Tetrahydrocannabinol Concentrations: Implications for Driving Interpretation and Drug Policy

Cited by 51 publications

References 31 publications

Ultra-high performance liquid chromatography tandem mass-spectrometry for simple and simultaneous quantification of cannabinoids

Ultra-high performance liquid chromatography tandem mass-spectrometry for simple and simultaneous quantification of cannabinoids

Effects of Marijuana Use on Brain Structure and Function

Driving under the influence of drugs

Contact Info

Product

Resources

About