Related Papers
Traffic Injury Prevention Delays in DUI blood testing: Impact on cannabis DUI assessments
Phillip Drum, PharmD, Ed Wood
Objective: This study examined the time fromlaw enforcement dispatch to the first blood draw in cases of driving under the influence (DUI) vehicular homicide and a subset of DUI vehicular assault cases in Colorado in 2012. Laboratory toxicology resultswere also examined to understand the implications of delays in blood draws in cases of driving while under the influence of marijuana’s delta-9-tetrahydrocannabinol (THC). Methods: Colorado court records were reviewed and information regarding charges, presence of alcohol and/or drugs, time of lawenforcement contact and blood draw, crash location, and other contextual factors were identified. The distributions of first blood draw times were studied by charge and by responding law enforcement agency. Toxicology data from a different cohort of DUI traffic arrests in Colorado and Washington were examined to determine the proportion of blood tests for THC that were above specified legal limits in those states. Results: The average time fromlawenforcement dispatch to blood drawin cases of vehicular homicide and vehicular assault was 2.32 h (SD ± 1.31 h), with a range of 0.83 to 8.0 h and a median of 2.0 h. Data from DUI traffic arrests found that between 42 and 70%of all cannabinoid-positive traffic arrests tested below5 ng/ml THC in blood, which is the legal limit in Colorado and Washington. Conclusion: Given the current delays to blood testing in cases of arrests for vehicular homicide and vehicular assault in Colorado, many blood tests are unlikely to confirm that driverswho are impaired from smoking marijuana have THC levels above established legal limits.
Clinical chemistry
Effect of Blood Collection Time on Measured Δ9-Tetrahydrocannabinol Concentrations: Implications for Driving Interpretation and Drug Policy
2016 •
David Gorelick
In driving-under-the-influence cases, blood typically is collected approximately 1.5-4 h after an incident, with unknown last intake time. This complicates blood Δ(9)-tetrahydrocannabinol (THC) interpretation, owing to rapidly decreasing concentrations immediately after inhalation. We evaluated how decreases in blood THC concentration before collection may affect interpretation of toxicological results. Adult cannabis smokers (≥1×/3 months, ≤3 days/week) drank placebo or low-dose alcohol (approximately 0.065% peak breath alcohol concentration) 10 min before inhaling 500 mg placebo, 2.9%, or 6.7% vaporized THC (within-individuals), then took simulated drives 0.5-1.3 h postdose. Blood THC concentrations were determined before and up to 8.3 h postdose (limit of quantification 1 μg/L). In 18 participants, observed Cmax (at 0.17 h) for active (2.9 or 6.7% THC) cannabis were [median (range)] 38.2 μg/L (11.4-137) without alcohol and 47.9 μg/L (13.0-210) with alcohol. THC Cmax concentration...
Transportation Research Record: Journal of the Transportation Research Board
Wreck on the Highway: Intersectionality of Driver Culpability, Tetrahydrocannabinols, Other Intoxicants and Fatalities in Washington State
2019 •
Mary Stohr
Given the legalization of recreational cannabis in 2012 in Washington State and recent mixed results regarding the effects of cannabis on driver safety, the paper examines the link between delta-9-tetrahydrocannabinols (THC) and driver behavior, including speeding and driver errors which may have contributed to a particular fatal crash. The current study utilized data from the Washington State Fatality Analysis Reporting System Analytical File (WA FARS) from 2008 to 2016. A series of logistic regressions were employed to compare THC-positive and -negative drivers, as well as drivers who tested positive for other intoxicants. The results of the study were mixed; it was found that delta-9-THC positively predicted speeding, but not other driver errors. Interestingly, carboxy-THC, a non-psychoactive chemical which can be detected for a longer period of time, was a significant predictor of both speeding and driver errors. This research further demonstrates that cannabis is predictive of ...
Clinical Chemistry
Cannabis-Impaired Driving: A Public Health and Safety Concern
2015 •
Marilyn Huestis
Journal of Safety Research
Ability to monitor driving under the influence of marijuana among non-fatal motor-vehicle crashes: An evaluation of the Colorado electronic accident reporting system
Karin A. Mack
Clinical Chemistry
Impact of Prolonged Cannabinoid Excretion in Chronic Daily Cannabis Smokers' Blood on Per Se Drugged Driving Laws
2013 •
Marilyn Huestis
Journal of pharmaceutical and biomedical analysis
Positive" urine testing for Cannabis is associated with increased risk of traffic crashes
2018 •
Silvia Mengozzi
Although recent Cannabis use is widely reported to be associated with drug-related traffic accidents, the evidence that Cannabis users show an increased risk of being involved in road crashes is still not unequivocally proved. The purpose of the present work is to provide an objective assessment of this hypothesis, by comparing the frequency of occurrence of positive urine analyses in drivers involved in traffic accidents (n = 1406) with that observed in a control population undergoing mandatory urine drug testing (n = 1953). Urine analyses for drugs of abuse were performed by screening immunometric techniques followed by confirmation with UHPLC-QQQ MS, adopting a cut-off concentration for THC-COOH of 15 ng/mL. A case was classified as "positive" when a driver admitted to hospital for road traffic injuries showed urine concentrations of THC-COOH higher than the cut-off. All samples showing positive results for any other controlled drug in urine or blood alcohol concentrati...
Injury Epidemiology
Trends in alcohol and marijuana detected in homicide victims in 9 US states: 2004–2016
oybek nazarov
Background Use of alcohol and other drugs is a major risk factor for assaultive injuries and violent deaths. The purpose of this study was to examine the time trends in the prevalence of alcohol and marijuana detected in homicide victims. Methods We analyzed toxicological testing data for homicide victims (n = 12,638) from the 2004–2016 National Violent Death Reporting System in 9 US states (Colorado, Georgia, Massachusetts, New Jersey, Oregon, Rhode Island, South Carolina, Virginia, and Wisconsin). We used the Cochran-Armitage test for trend to assess the statistical significance of changes in the prevalence of alcohol and marijuana detected in these homicide victims during the study period. Results Overall, 37.5% of the homicide victims tested positive for alcohol, 31.0% positive for marijuana, and 11.4% positive for both substances. During the study period, the prevalence of marijuana increased from 22.3% (95% confidence interval [CI] = 19.6, 25.0) in 2004 to 42.1% (95% CI = 39.2...
Journal of Analytical Toxicology
Blood Synthetic Cannabinoid Concentrations in Cases of Suspected Impaired Driving
2013 •
Barry Logan
Journal of Forensic Sciences
A Two‐Year Study of Δ 9 Tetrahydrocannabinol Concentrations in Drivers; Part 2: Physiological Signs on Drug Recognition Expert (DRE) and non‐DRE Examinations
2017 •
Ariana figueroa
