Tags

Type your tag names separated by a space and hit enter

Driving under the influence of cannabis: a 10-year study of age and gender differences in the concentrations of tetrahydrocannabinol in blood.
Addiction. 2008 Mar; 103(3):452-61.A

Abstract

BACKGROUND

Delta(9)-Tetrahydrocannabinol (THC) is the major psychoactive constituent of cannabis and its various preparations. Increasing use of cannabis for recreational purposes has created a problem for road-traffic safety. This paper compares age, gender and the concentrations of THC in blood of individuals apprehended for driving under the influence of drugs (DUID) in Sweden, where a zero-tolerance law operates.

MEASUREMENTS

Specimens of blood or urine were subjected to a broad screening analysis by enzyme immunoassay methods. THC positives were verified by analysis of blood by gas chromatography-mass spectrometry (GC-MS) with a deuterium-labelled internal standard (d(3)-THC). All toxicology results were entered into a database (TOXBASE) along with the age and gender of apprehended drivers.

FINDINGS

Over a 10-year period (1995-2004), between 18% and 30% of all DUID suspects had measurable amounts of THC in their blood (> 0.3 ng/ml) either alone or together with other drugs. The mean age [+/- standard deviation (SD)] of cannabis users was 33 +/- 9.4 years (range 15-66 years), with a strong predominance of men (94%, P < 0.001). The frequency distribution of THC concentrations (n = 8794) was skewed markedly to the right with mean, median and highest values of 2.1 ng/ml, 1.0 ng/ml and 67 ng/ml, respectively. The THC concentration was less than 1.0 ng/ml in 43% of cases and below 2.0 ng/ml in 61% of cases. The age of offenders was not correlated with the concentration of THC in blood (r = -0.027, P > 0.05). THC concentrations in blood were higher when this was the only psychoactive substance present (n = 1276); mean 3.6 ng/ml, median 2.0 ng/ml compared with multi-drug users; mean 1.8 ng/ml, median 1.0 ng/ml (P < 0.001). In cases with THC as the only drug present the concentration was less than 1.0 ng/ml in 26% and below 2.0 ng/ml in 41% of cases. The high prevalence of men, the average age and the concentrations of THC in blood were similar in users of illicit drugs (non-traffic cases).

CONCLUSIONS

The concentration of THC in blood at the time of driving is probably a great deal higher than at the time of sampling (30-90 minutes later). The notion of enacting science-based concentration limits of THC in blood (e.g. 3-5 ng/ml), as discussed in some quarters, would result in many individuals evading prosecution. Zero-tolerance or limit of quantitation laws are a much more pragmatic way to enforce DUID legislation.

Authors+Show Affiliations

Department of Forensic Genetics and Forensic Toxicology, National Board of Forensic Medicine, Sweden. wayne.jones@rmv.seNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

18190663

Citation

Jones, Alan W., et al. "Driving Under the Influence of Cannabis: a 10-year Study of Age and Gender Differences in the Concentrations of Tetrahydrocannabinol in Blood." Addiction (Abingdon, England), vol. 103, no. 3, 2008, pp. 452-61.
Jones AW, Holmgren A, Kugelberg FC. Driving under the influence of cannabis: a 10-year study of age and gender differences in the concentrations of tetrahydrocannabinol in blood. Addiction. 2008;103(3):452-61.
Jones, A. W., Holmgren, A., & Kugelberg, F. C. (2008). Driving under the influence of cannabis: a 10-year study of age and gender differences in the concentrations of tetrahydrocannabinol in blood. Addiction (Abingdon, England), 103(3), 452-61. https://doi.org/10.1111/j.1360-0443.2007.02091.x
Jones AW, Holmgren A, Kugelberg FC. Driving Under the Influence of Cannabis: a 10-year Study of Age and Gender Differences in the Concentrations of Tetrahydrocannabinol in Blood. Addiction. 2008;103(3):452-61. PubMed PMID: 18190663.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Driving under the influence of cannabis: a 10-year study of age and gender differences in the concentrations of tetrahydrocannabinol in blood. AU - Jones,Alan W, AU - Holmgren,Anita, AU - Kugelberg,Fredrik C, Y1 - 2008/01/08/ PY - 2008/1/15/pubmed PY - 2008/6/11/medline PY - 2008/1/15/entrez SP - 452 EP - 61 JF - Addiction (Abingdon, England) JO - Addiction VL - 103 IS - 3 N2 - BACKGROUND: Delta(9)-Tetrahydrocannabinol (THC) is the major psychoactive constituent of cannabis and its various preparations. Increasing use of cannabis for recreational purposes has created a problem for road-traffic safety. This paper compares age, gender and the concentrations of THC in blood of individuals apprehended for driving under the influence of drugs (DUID) in Sweden, where a zero-tolerance law operates. MEASUREMENTS: Specimens of blood or urine were subjected to a broad screening analysis by enzyme immunoassay methods. THC positives were verified by analysis of blood by gas chromatography-mass spectrometry (GC-MS) with a deuterium-labelled internal standard (d(3)-THC). All toxicology results were entered into a database (TOXBASE) along with the age and gender of apprehended drivers. FINDINGS: Over a 10-year period (1995-2004), between 18% and 30% of all DUID suspects had measurable amounts of THC in their blood (> 0.3 ng/ml) either alone or together with other drugs. The mean age [+/- standard deviation (SD)] of cannabis users was 33 +/- 9.4 years (range 15-66 years), with a strong predominance of men (94%, P < 0.001). The frequency distribution of THC concentrations (n = 8794) was skewed markedly to the right with mean, median and highest values of 2.1 ng/ml, 1.0 ng/ml and 67 ng/ml, respectively. The THC concentration was less than 1.0 ng/ml in 43% of cases and below 2.0 ng/ml in 61% of cases. The age of offenders was not correlated with the concentration of THC in blood (r = -0.027, P > 0.05). THC concentrations in blood were higher when this was the only psychoactive substance present (n = 1276); mean 3.6 ng/ml, median 2.0 ng/ml compared with multi-drug users; mean 1.8 ng/ml, median 1.0 ng/ml (P < 0.001). In cases with THC as the only drug present the concentration was less than 1.0 ng/ml in 26% and below 2.0 ng/ml in 41% of cases. The high prevalence of men, the average age and the concentrations of THC in blood were similar in users of illicit drugs (non-traffic cases). CONCLUSIONS: The concentration of THC in blood at the time of driving is probably a great deal higher than at the time of sampling (30-90 minutes later). The notion of enacting science-based concentration limits of THC in blood (e.g. 3-5 ng/ml), as discussed in some quarters, would result in many individuals evading prosecution. Zero-tolerance or limit of quantitation laws are a much more pragmatic way to enforce DUID legislation. SN - 0965-2140 UR - https://www.unboundmedicine.com/medline/citation/18190663/Driving_under_the_influence_of_cannabis:_a_10_year_study_of_age_and_gender_differences_in_the_concentrations_of_tetrahydrocannabinol_in_blood_ L2 - https://doi.org/10.1111/j.1360-0443.2007.02091.x DB - PRIME DP - Unbound Medicine ER -