Transport Research International Documentation (TRID)

Drug prevalence in Canadian driving population

Tue, 14 Apr 2026 16:59:47 GMT

ObjectiveIn 2024 a drug prevalence roadside survey was performed in the Yukon territory of Canada. In 2024 a drug prevalence roadside survey was performed in the Yukon territory of Canada. Volunteer drivers on Wednesday through Saturday nights June through August 2024 were asked to donate oral fluid samples and participate in a questionnaire of drug use. Samples were collected from 294 noncommercial and 220 commercial drivers. Oral fluid sample collection was chosen due to the ease of collection for the donor. Drugs in oral fluid are indicative of those compounds in the blood at the time of collection. Drugs are deposited in oral fluid by diffusion from blood or coating the oral mucosa. Studies have shown similar drug class results when oral fluid and blood are compared (Kelley-Baker et al. 2014). The objective of this paper is to perform additional screening by liquid chromatography time of flight mass spectrometry (LC-QTOF-MS) on all samples for the Tier I and II compounds as suggested by NSC-ADID recommendations. Oral fluid samples were collected at the roadside using the Quantisal™ collection device and shipped overnight to 9 Delta Analytical, LLC where they were screened for delta 9-tetrahydrocannabinal, amphetamines, cocaine, benzodiazepines, and opiates including fentanyl. Initial screening was performed using a liquid chromatograph tandem mass spectrometer (LC-MS/MS). Screening parameters were fully validated and published in a peer reviewed journal (Coulter et al. 2022). All samples screening positive were confirmed by LC-MS/MS using a second sample aliquot. Additional testing resulted in an increased positivity rate for both driving cohorts. Positivity rates increased to 25% for both groups with polydrug use seen in 7.5% and 4.5% for noncommercial and commercial drivers respectively. Statistical analysis showed THC concentrations were different between the two driving groups. The mean concentration for THC in noncommercial drivers was 29 ng/mL compared to 8 ng/mL for commercial drivers, when high concentration outliers were removed. Additional discoveries of over the counter and antidepressant medication were made using Tier I and II recommendations. The NSC-ADID Tier I and II recommendations should be followed when conducting drug prevalence surveys of drivers. LC-QTOF-MS is the recommended tool to conduct drug screening for oral fluid samples.

Drug driving in Italy. The results of the first roadside drug testing service utilizing on-site confirmatory analysis between 2019 and 2022.

Tue, 23 Apr 2024 10:53:17 GMT

Drug driving represents a public safety concern, and the size of this issue in Italy is not fully known. Drug testing is composed of two steps: 1) screening and 2) confirmatory analysis. The second step, and the associate medical examination to assess the state of impairment, usually are not performed right after the screening as they require specialized personnel and instrumental equipment that are not historically available at roadblocks. These pitfalls make this process both complicated and time-consuming. A mobile laboratory was set up in 2019 by the Forensic Lab Service S.r.l. (limited liability company) to improve roadblock timing, planning, as well as to shed light on the extent of the drug driving issue in Italy. Drug screenings were performed using DrugWipe® Saliva testing. Confirmatory analysis was performed on oral fluids by liquid chromatography coupled with tandem mass spectrometry. A dedicated room of the mobile laboratory was also designed for drug driving medical assessment.2,082 samples were collected during 88 road safety services held in different locations across Italy. In total, 9% of the tested subjects were positive to both the screening and the confirmatory analysis. The most prevalent illicit drugs found in this study were THC (72%), followed by cocaine (41%). Drug drivers were mostly male (93%) and younger than 30 years of age (58%). The prevalence of drivers testing positive for illicit drugs resulted to be higher compared to the results obtained in the DRUID project and to other surveys previously performed in Italy. These data demonstrate the need for control services to improve road safety in regards to drug driving.

Trends in drivers testing positive for drugs of abuse in oral fluid from 2018 to 2021 in France

Wed, 15 Nov 2023 09:19:57 GMT

Driving under the influence of drugs (DUID) is a risk factor for traffic accidents. The testing of oral fluid by roadside immunochromatography and laboratory-confirmed chromatography coupled to mass spectrometry (LC-MS/MS) analysis to detect drug abuse has increased in France. The aim of this study was to describe the trends observed in drivers testing positive for illicit drugs in oral fluid and to investigate the concordance between the two analytical methods used. The authors received for confirmation 3051 oral fluid samples from drivers who had tested positive at the roadside with a Drugwipe-5S® device between 2018 and 2021 around Grenoble, France. Samples were collected with FLOQSwab® and analyzed by LC-MS/MS (THC, amphetamine, methamphetamine, MDMA and MDA, MDEA, cocaine and benzoylecgonine, morphine and 6-monoacetylmorphine) at Grenoble Alpes University Hospital, France. Binomial logistic regression was performed to evaluate consumption trends. Most of the drivers were men (93.2%), with a median age of 26 years (range: 14–66 years). Cannabis (94.6%) cocaine (17.5%) and MDMA (2.5%) were the drugs most frequently detected. Poly-drug use was observed in 17.3% of drivers and involved cannabis and cocaine in 85.3% of these drivers. Poly-drug use was more frequent among drivers over the age of 32 years (OR, 3.48; 95% CI, 2.59–4.68; p ≤ .001), as was cocaine use (OR, 5.15; 95% CI, 3.75–7.08; p ≤ .001). The frequency of positive tests for amphetamines was higher in women than in men (OR, 2.53; 95% CI, 1.50–4.27; p ≤ .001). The positive predictive value of Drugwipe-5S was 98.2% for cannabis, 22.6% for amphetamines, 75.4% for cocaine and 17.3% for opiates. At least one discrepancy between Drugwipe-5S® and LC-MS/MS results was observed for 22.3% of the samples tested. The authors report recent trends for drivers testing positive for illicit drugs in oral fluid in France. Cannabis was the most prevalent drug of abuse identified, suggesting that a general prevention program might be useful. The results also highlight the need for LC-MS/MS confirmation when screening oral fluid for drugs of abuse.

Use of psychoactive substances by goods carriage drivers associated with Kerala, India

Mon, 16 Oct 2023 14:01:22 GMT

ObjectiveThis study aimed to measure the prevalence of drugs of abuse (DOA) among the goods carriage drivers associated with the southern State of India, Kerala.MethodsPoint-of-collection testing (POCT) of oral fluid collected from the participants (n?=?249) was done using the Evidence MultiSTAT DOA Oral Fluid II Assay kits and the Evidence MultiSTAT analyzer.ResultsOut of the total samples, 53 (21.29%) were positive for one or more DOA. A high prevalence of tetrahydrocannabinol (THC) (10.04%) and synthetic cannabinoids were detected in the samples. The use of ketamine, alpha-PVP, LSD, methamphetamine, opiate, 6-MAM, benzodiazepines I, methadone, PCP, tramadol, and amphetamine was also detected and their frequency of use ranged between 4.02 and 0.80%. An association between drug abuse and distance of travel was found in drivers in this study, ?2 (5, N?=?249)?=?123.5, p?

The Utility of Delta 9-Tetrahydrocannabinol (THC) Measures Obtained from Oral Fluid Samples in Traffic Safety

Tue, 17 Dec 2019 14:13:43 GMT

Blood and/or urine are typical drug detection matrices used by law enforcement. There are some concerns about using oral fluid (OF) in the identification of drivers potentially impaired by cannabis, particularly regarding their accuracy when compared to blood. The study objectives were to (1) examine the accuracy of predicting delta 9-tetrahydrocannabinol (THC) in blood from THC measured in OF and (2) examine factors influencing prediction accuracy. Using data from the 2007 and 2013–2014 National Roadside Survey (NRS) of Alcohol and Drug Use, 7,517 drivers with known laboratory results in both OF and blood were included in this study. OF samples were collected using the Quantisal® device and analyzed at the same private laboratory in both the 2007 and 2013–2014 NRS. The Quantisal device has consistently shown to collect 1 mL ±10%. Descriptive statistical analyses were used to examine and compare the distribution of THC concentrations in OF and blood. A hurdle model was applied to examine factors influencing the accuracy of the THCblood predictions based on THCOF while accounting for the decisions of cannabis consumption. The authors estimated the number of true positives (TPs), false positives (FPs), true negatives (TNs), false negatives (FNs), sensitivity, specificity, and positive predicted value (PPV). Results: This study found that THC measured in OF (THCOF) is a good predictor of THC measured in blood (THCblood), in particular when THCOF > 0 ng/mL is used to predict being positive for THCblood (THCblood > 0 ng/mL). However, as blood and OF concentrations depart from 0 ng/mL, the proportion of TPs (sensitivity) decreases, which might be a concern for law enforcement. The likelihood of accurately predicting THCblood from THCOF is lower for drivers who were simultaneously using cannabis and other drugs. The findings of this study are based on THC measures obtained in a laboratory, which may not be the same as those conducted by police using point-of-care devices. However, this study is unique due to its large sample of drivers obtained in similar roadside locations and times to actual law enforcement activities. Though a positive THCOF may assist law enforcement in probable cause for a blood draw, efforts to develop reliable methods to detect drug impairment based on OF should continue.

Driving under the influence of psychostimulant drugs: Effects on cognitive functioning among truck drivers in Brazil

Mon, 16 Dec 2019 11:32:05 GMT

Brazil has one of the highest traffic accident rates in the world. Cargo vehicles are the second most common type of vehicle involved in these accidents. Driving under the influence of drugs increases the risk of truck drivers being involved in road traffic injuries or fatalities. Psychostimulant drug use among truck drivers is of particular interest, as they use these drugs to maintain their occupational performance. The aim of this study is to identify the prevalence of psychostimulant drug use among truck drivers through toxicological analyses of urine and saliva samples and to evaluate its effects on the drivers’ performance on attention level and executive functioning tests. A nonprobabilistic sample of 684 truck drivers was recruited at truck stops along three highways in Sao Paulo, Brazil. Participants were requested to answer questions on personal information and work-related matters via a structured research instrument. Afterwards, they were asked to perform four cognitive tests and to complete other questionnaires on confounding variables. Strict exclusion criteria were enforced. Descriptive and inferential analyses were performed in the Minitab 18.1 and R programs, version 3.5.3. Then, the variables from the cognitive performance tests were included as response variables in the generalized linear regression models, separately, correcting for the effects from confounding variables. 504 drivers were excluded from the data analysis due to health conditions that prevented them from safely participating in a cognitive performance evaluation. Therefore, 180 drivers remained in the sample; among them, 44 participants were categorized as users, and 136 were categorized as nonusers. The drug users performed better than the nonusers in almost all the cognitive tests in the univariate analysis. However, after controlling for the effects of confounding variables, the authors observed that despite drug users being faster at performing some tests, they committed more errors and had lower precision rates than nonusers in other measures. Moreover, users dealt with tasks that involved alternate and divided attention more poorly than nonusers. Psychostimulant drug use may initially seem advantageous to truck drivers since it allows users to maintain their attention for longer periods of time; however, the onus related to that use is much larger and should therefore be avoided by truck drivers and policed by competent authorities.

Roadside Drug Tests Often Contradict Driver Statements

Fri, 13 Dec 2019 17:05:29 GMT

This article summarizes a recent study conducted by the Insurance Institute for Highway Safety (IIHS) that compared self-reported drug use with drug test results. As expected, drivers are reluctant to admit to taking drugs within 24 hours of driving, even when the drugs used are legal. This study used data collected in two different national roadside survey efforts (2007 and 2013-2014), which included both biological and self-reported information from more than 7,000 drivers in each survey. For this additional analysis, IIHS researchers focused on the results related to cannabis, opioids, cocaine, antidepressants, and benzodiazepines (e.g., Valium, Xanax). The author contends that these findings support the importance of conducting blood or saliva tests, rather than relying solely on self-report, to understand the extent of the drug-impaired driving problem. Readers are referred to the full report by emailing researchpapers@iihs.org.

Detection Windows for Drugs in Oral Fluid: Cannabinoids, Stimulants, and Opioids

Wed, 31 Jul 2019 15:31:55 GMT

In impaired driving enforcement, blood has traditionally been the preferred biological specimen in determining the presence of drugs in drivers. However, collecting blood specimens from drivers can be challenging, often resulting in delays impacting test results and noncompliance. The use of oral fluid as a matrix for the analysis of drugs is gaining popularity and an increasing number of research studies substantiate the correlation between drug concentrations in oral fluid and blood (Bosker & Huestis, 2009; Busardo et al., 2018). Drugs may be deposited in oral fluid via ingestion (e.g., smoked or oral) and passive diffusion from blood into saliva (Lee & Huestis, 2014). As a detection matrix, oral fluid has several advantages over blood and urine: collection is easy, noninvasive, and can be observed, limiting opportunities for adulteration. Oral fluid also can be collected at the roadside, close to the time of a suspected impaired driving offense. However, there is still much to be learned about the use of oral fluid especially as a detection matrix at the roadside. The objective of this research brief is to assess the literature on oral fluid detection times to address how long after a person uses a drug it can be detected in oral fluid, and what factors may influence detection times. As drug prevalence does not imply impairment, efforts to understand the proximity of drivers’ drug use in time may assist in better understanding and properly enforcing drug-impaired driving laws.

Detection of Illicit Drugs in Oral Fluid from Drivers as Biomarker for Drugs in Blood

Tue, 08 Dec 2015 10:02:32 GMT

This study was undertaken to assess whether analysis of oral fluid can be used to identify individual drivers with drug concentrations in blood above 25 ng/mL for amphetamine and methamphetamine, 10 ng/mL for cocaine and 1.0 ng/mL for tetrahydrocannabinol (THC), which are the cut-off concentrations used in the European DRUID Project, by calculating the diagnostic accuracies when using the analytical cut-off concentrations in oral fluid as well as for the optimal cut-off concentrations. Paired samples of whole blood and oral fluid collected with the Statsure Saliva Sampler were obtained from 4080 drivers in four European countries and analyzed for amphetamine, methamphetamine, cocaine and THC using GC-MS or LC-MS. The vast majority (89%) were random drivers not suspected of drug-impaired driving. Receiver-Operating Characteristic analysis was used to evaluate the analytical results. The prevalence of drug findings above the cut-off concentrations in blood was 1.3% for amphetamine, 1.0% for methamphetamine, 0.6% for cocaine and 1.3% for THC. The cut-off concentrations in oral fluid that gave the highest diagnostic accuracy were for amphetamine 130 ng/mL (accuracy 99.8%), methamphetamine 280 ng/mL (accuracy 99.9%), cocaine 570 ng/mL (accuracy 99.6%), and THC 38 ng/mL (accuracy 98.3%). The proportion of false positives were 0.2%, 0.1%, 0.1% and 0.9%; and the proportion of false negatives were 0.1%, 0.0%, 0.3% and 0.8%, respectively, when using those cut-offs. The positive predictive values were 87.9%, 92.9%, 84.6% and 35.7% for amphetamine, methamphetamine, cocaine and THC, respectively. Analysis of concentrations of illicit drugs in oral fluid could not be used to accurately identify drivers with drugs concentrations above the selected cut-offs in blood in a cohort of drivers with low prevalence of drugs.

Illicit drugs and driving: an investigation of fatalities and traffic offences in Western Australia

Fri, 15 May 2015 12:21:05 GMT

The prevalence and characteristics of illicit drug related driving in Western Australia was investigated through the analysis of the records of drivers and riders fatally injured in the period 2000-2012 and drivers and riders charged with a Section 64AC offence (illicit substance in oral fluid), 2008-2012. Approximately 23% of fatally injured drivers/riders tested positive to one or more illicit substances with the annual rate of detection unchanged for the full study period, with some preliminary evidence of a decline from 2008. The odds of testing positive was significantly higher for males, those aged under 40 years; those driving without a valid licence; those testing positive to alcohol in the range 0.05gm%-0.149gm%, and those using benzodiazepines with and without opioids. Around 4% of drivers and riders undertaking a roadside oral fluid test 2008-2012 were charged with a Section 64AC offence. The annual offence rate significantly increased over the period. Offending was highest in males, younger age drivers/riders, and in the metropolitan area and select metropolitan police districts. A number of recommendations were provided covering issues such as data sharing, changes to the roadside oral fluid testing program, penalties, and research.

Correlates of Drug Use and Driving Among Undergraduate College Students

Thu, 29 May 2014 16:47:16 GMT

The National Roadside Survey is a study undertaken in the United States to determine the prevalence of alcohol and drugs in randomly selected drivers. Following the success of a 2006 pilot study, the 2007 survey incorporated, for the first time, the collection of biological specimens for drug analysis. This article compares the results obtained from blinded analyses of pairs of oral fluid and blood samples obtained from the same subject. During the 2007 survey, more than 7000 nighttime drivers were randomly stopped and surveyed for their self-reported drug use and were requested to donate an oral fluid specimen using the Quantisal (Immunalysis Corporation, Pomona, CA) device and a blood sample. Overall, 5869 oral fluid specimens were collected from nighttime drivers with 3236 corresponding blood samples. Biological specimens were analyzed for a wide range of drugs. At nighttime, 14.4 percent of the drivers were positive for drugs in oral fluid, with just over half of those having marijuana present (7.6%). Of the 3236 pairs of specimens, 2676 were negative for all drugs, and 326 matched pairs of samples were both positive, out of which 247 (75.8%) were an exact match for all drug classes and 70 (21.5%) were positive for at least one common drug class. Oral fluid and blood samples provided very similar information regarding recent drug intake by randomly tested drivers and oral fluid yielded a higher detection rate for one drug (cocaine) than blood. Oral fluid can be considered a reliable alternative to blood as a matrix for drug testing.

Comparing Drug Detection in Oral Fluid and Blood: Data from a National Sample of Nighttime Drivers

Thu, 29 May 2014 09:28:47 GMT

Drug use among drivers who drank on alcohol outlets from Porto Alegre, Brazil

Tue, 25 Feb 2014 09:15:19 GMT

Background: Driving under the influence of multiple substances is a public health concern, but there is little epidemiological data about their combined use and putative impact on driving in low and middle-income countries where traffic crashes have been clustering in recent years. The aim of this study is to estimate the prevalence of alcohol and drug use – as well as their associated factors – among drivers in the context of alcohol outlets (AOs). Methods: A probability three-stage sample survey was conducted in Porto Alegre, Brazil. Individuals who were leaving AO were screened, with the selection of 683 drivers who met the inclusion criteria. Drivers answered a structured interview, were breathalyzed, and had their saliva collected for drug screening. Prevalences were assessed using domain estimation and logistic regression models assessed covariates associated with substance use. Findings: Benzodiazepines 3.9% (SE 2.13) and cocaine 3.8% (SE 1.3) were the most frequently detected drugs in saliva. Among drivers who were going to drive, 11% had at least one drug identified by the saliva drug screening, 0.4% two, and 0.1% three drugs in addition to alcohol. In multivariable analyses, having a blood alcohol concentration (BAC) > 0.06% was found to be associated with a 3.64 times (CI 95% 1.79–7.39) higher chance of drug detection, compared with interviewees with lower BACs. Conclusions: To drive under the influence of multiple substances is likely to be found in this setting, highlighting an association between harmful patterns of consume of alcohol and the misuse of other substances.

On-site testing of cannabis: a controlled study after smoking cannabis

Thu, 05 Dec 2013 08:47:24 GMT

Collection and analysis of drugs in oral fluid using conventional on-site test devices is time consuming, often taking more than 10 minutes. The BIOSENS system, utilizes an alternative approach which implies collection of mucus from the mucosal surface from the tongue with a special designed Oral Mucus Collector (OMC), subsequently analyzed in a BIOSENS system. The collection procedure takes a few seconds and the analysis procedure approximately 60 seconds. The aim of this study is to determine the window of detection and cut off values for THC (delta-9-tetrahydrocannabinol) using the BIOSENS system after smoking one single cannabis cigarette. Eight subjects smoked one cannabis cigarette (THC content 0.3mg/kg body weight). Conventional oral fluid samples and oral mucus samples were collected prior smoking and 1, 2, 3, 4, 5, 6h after smoking. The window of detection using the BIOSENS system was found to be 4 hours for four of the eight subjects, 3h for one subject, 2h for one subject, 1h for one subject and less than 1h for one subject. The window of detection after smoking a single cannabis cigarette was 3-4 hours and the very short sample collection/analysis time opens up possibilities to detect DUI (Driving Under Influence) in practical way. The window of detection is similar to the acute impairment window reported elsewhere. Apart from cannabis, we have observed that other drugs are accumulated in the mucosal surface of the tongue as well. The overall results showed that the BIOSENS system is applicable as an efficient screening method for detecting recent drug use.

Development of North American consensus guidelines for toxicological investigation of impaired driving and traffic fatalities cases

Thu, 05 Dec 2013 08:47:18 GMT

The objective of the project was to develop a set of guidelines that laboratories could follow to ensure uniformity of practice, relevant testing parameters, and create comparable datasets for epidemiological study and forensically defensible toxicology results for use in criminal cases. In November 2012, a set of recommendations were finalized based on consideration of analytical capabilities of most laboratories, toxicologically relevant concentrations, and prevalence data from the participating laboratories. Specific recommendations for the analytical approach were made based on the principle of an initial immunological screen of defined scope to include opiates, oxycodone, benzodiazepines (plus lorazepam, clonazepam), cannabinoids, amphetamine, methamphetamine, cocaine metabolite, methadone, carisoprodol, barbiturates, PCP, and zolpidem with quantitative confirmation by gas or liquid chromatography with mass spectrometry. The Panel also considered and established screening and confirmation thresholds for urine and oral fluid. Urine was generally seen as a less preferable sample, and while very few laboratories currently test for drugs in oral fluid, its value as a specimen in DUID casework was recognized. The laboratory recommendations will be published in early 2013.