Roadside Testing Research Articles

In vitro biotransformation of 3-methylmethcathinone (3-MMC) through incubation with human liver microsomes and cytosol and application to in vivo samples

Synthetic cathinones are the second largest group of new psychoactive substances (NPS) monitored by the European Monitoring Centre for Drugs and Drug Addiction. Although 3-methylmethcathinone (3-MMC, C11H15NO) is legally banned in many countries, it is readily available for purchase online and on the street. Due to the scarcity of information regarding the pharmacokinetic and toxicological profile of 3-MMC, understanding its biotransformation pathways is crucial in determining its potential toxicity in humans and in the development of analytical methods for screening of human matrices. To gain more insight, Phase I and Phase II in vitro biotransformation of 3-MMC was investigated using human liver microsomes and human liver cytosol. Suspect and non-target screening approaches were employed to identify metabolites. To confirm in vitro results in an in vivo setting, human matrices (i.e., plasma, urine, saliva and hair) positive for 3-MMC (n=31) were screened. In total three biotransformation products were identified in vitro: C11H15NO2 (a hydroxylated derivate), C11H17NO (a keto-reduced derivate) and C10H13NO (an N-desmethyl derivate). All three were confirmed as human metabolites in respectively 16 %, 52 % and 42 % of the analysed human samples. In total, 61 % of the analysed samples were positive for at least one of the three metabolites. Interestingly, three urine samples were positive for all three metabolites. The presence of 3-MMC in saliva and hair indicates its potential applicability in specific settings, e.g., roadside testing or chronic consumption analysis. To our knowledge, C11H17NO was not detected before in vivo. Although some of these metabolites have been previously suggested in vitro or in a single post mortem case report, a wide in vivo confirmation including the screening of four different human matrices was performed for the first time. These metabolites could serve as potential human biomarkers to monitor human 3-MMC consumption effectively.

An analytical approach for on-site analysis of breath samples for Δ9-tetrahydrocannabinol (THC).

Increased acceptance of cannabis containing the psychoactive component, Δ9-tetrahydrocannabinol (THC), raises concerns about the potential for impaired drivers and increased highway accidents. In contrast to the "breathalyzer" test, which is generally accepted for determining the alcohol level in a driver, there is no currently accepted roadside test for THC in a motorist. There is a need for an easily collectible biological sample from a potentially impaired driver coupled with an accurate on-site test to measure the presence and quantity of THC in a driver. A novel breath collection device is described, which includes three separate sample collectors for collecting identical A, B, and C breath samples from a subject. A simple one-step ethanol extraction of the "A" breath collector sample can be analyzed by UHPLC/selected ion monitoring (SIM) liquid chromatography/mass spectrometry (LC/MS) to provide qualitative and quantitative determination of THC in breath sample in less than 4 min for samples collected up to 6 h after smoking a cannabis cigarette. SIM LC/MS bioanalyses employed d3-THC as the stable isotope internal standard fortified in negative control breath samples for quantitation including replicates of six calibrator standards and three quality control (QC) samples. Subsequent confirmation of the same breath sample in the B collectors was then confirmed by a reference lab by LC/MS/MS analysis. Fit-for-purpose bioanalytical validation consistent with pharmaceutical regulated bioanalyses produced pharmacokinetic (PK) curves for the two volunteer cannabis smokers. These results produced PK curves, which showed a rapid increase of THC in the breath of the subjects in the first hour followed by reduced THC levels in the later time points. A simpler single-point calibration curve procedure with calibrators and QC prepared in ethanol provided similar results. Limitations to this approach include the higher cost and operator skill sets for the instrumentation employed and the inability to actually determine driver impairment.

Characterization of Motorcycle Encroachments in the U.S

In 2020, there were 5,579 motorcyclist fatalities in the U.S., which is the highest on record. Despite accounting for only 3% of registered vehicles, motorcycles are involved in 42% of fatal guardrail impacts. Roadside safety hardware testing guidelines are outlined in the Manual for Assessing Safety Hardware (MASH) for passenger vehicles and large trucks but these procedures do not include any motorcycle impacts. Although international test procedures for roadside hardware prescribe motorcycle crash tests, it is not known if the prescribed test conditions reflect the conditions at which motorcycles depart the roadway in the U.S. A better understanding of the characteristics of motorcycles departing the roadway in the U.S. is needed before the development of motorcycle crash tests. This study used the National Cooperative Highway Research Program (NCHRP) 17-88 database to compare the encroachment and impact characteristics of motorcycles, passenger vehicles, single-unit trucks, and tractor-trailer trucks. Motorcycles were found to have a similar distribution of impact angles to passenger vehicles, with an 85th percentile of 24 degrees. The median and 85th percentile impact angle was found to be shallower for tractor-trailer trucks compared with motorcycles and passenger vehicles. Additionally, large trucks and motorcycles were found to roll over at a higher frequency than passenger vehicles. During the first event, almost 80% of motorcycles were upright. By the second event, almost 50% of motorcyclists were separated from the motorcycle. This indicates that a large percentage of riders lose contact with the motorcycle during the first event and are separated during any subsequent events. Based on these results, future motorcycle-barrier tests should consider an upright configuration and an impact angle of 24 degrees.

Marijuana: Forensics of Abuse, Medical Uses, Controversy, and AI

Motor vehicle accidents are a significant consequence of marijuana abuse. Limitations of its roadside detection and the forensic problems with establishing impairment require innovations that are scientifically achievable. Marijuana abuse currently is at an all-time high in the United States and its physiological effects make it a popular recreational drug that is reported to be a leading cause of preventable morbidity and mortality among the youth in the 18 most affluent nations. The medical benefits of drugs derived from marijuana complicate its forensic regulation. In an extensive 2017 report by The American Academy of Sciences, the evidence for the medical benefits of delta-9 tetrahydrocannabinol (derived from marijuana) were stated to be conclusive or substantial for the treatment of chronic pain in adults, as an antiemetic for treatment of chemotherapy-induced nausea and vomiting, and for improving patient-reported multiple sclerosis spasticity symptoms. The benefits from treatment for many other medical conditions were inconclusive or absent. The evidence is clear that safely driving a motor vehicle is significantly impaired while under the influence of marijuana. However, there is no roadside forensic test that reliably detects impairment, and there is an urgent need for such to protect the public while insuring the legal rights of users. There is strong societal pressure to relax marijuana’s forensic regulation, including removing it from Schedule I of the Controlled Substances Act. Artificial intelligence (AI) should be implemented with appropriate human control to resolve controversies.

Differential pulsed voltammetry of Δ9‐Tetrahydrocannabinol (THC) on disposable screen‐printed carbon electrodes: A potential in‐field method to detect Δ9‐THC in saliva

AbstractDue to recent legalization of marijuana across many states in the U.S., there is an increased concern of users driving while impaired/intoxicated with Δ9‐tetrahydrocannabinol (Δ9‐THC), the principal psychoactive constituent of cannabis/marijuana. Hence, there is a need for a rapid roadside detection of this drug that can be used to accurately screen drivers. Current field sobriety tests rely on a series of physical and mental exercises administered during DUI investigations to help determine a driver's level of impairment. Due to their portability and effectiveness, screen printed carbon electrodes (SPCEs) are ideal to work with when it comes to devising a low‐cost screening device for roadside testing. SPCE's can potentially detect low levels of Δ9‐THC in an individual's saliva via electrochemical oxidation of Δ9‐THC. Herein we report a fast, cheap, and accurate approach to electrochemically detect 1–20 μM Δ9‐THC in a 1 mL sample of artificial oral fluid (AF‐OF) diluted to 50 % with a buffer/electrolyte solution using differential pulse voltammetry (DPV) at the surface of a small SPCE. Implications for the use of this method to screen intoxicated drivers are discussed.

Metabolomics-based Sleepiness Markers for Risk Prevention and Traffic Safety (ME-SMART): a monocentric, controlled, randomized, crossover trial

BackgroundToo little sleep and the consequences thereof are a heavy burden in modern societies. In contrast to alcohol or illicit drug use, there are no quick roadside or workplace tests for objective biomarkers for sleepiness. We hypothesize that changes in physiological functions (such as sleep–wake regulation) are reflected in changes of endogenous metabolism and should therefore be detectable as a change in metabolic profiles. This study will allow for creating a reliable and objective panel of candidate biomarkers being indicative for sleepiness and its behavioral outcomes.MethodsThis is a monocentric, controlled, randomized, crossover, clinical study to detect potential biomarkers. Each of the anticipated 24 participants will be allocated in randomized order to each of the three study arms (control, sleep restriction, and sleep deprivation). These only differ in the amount of hours slept per night. In the control condition, participants will adhere to a 16/8 h wake/sleep regime. In both sleep restriction and sleep deprivation conditions, participants will accumulate a total sleep deficit of 8 h, achieved by different wake/sleep regimes that simulate real-life scenarios. The primary outcome is changes in the metabolic profile (i.e., metabolome) in oral fluid. Secondary outcome measures will include driving performance, psychomotor vigilance test, d2 Test of Attention, visual attention test, subjective (situational) sleepiness, electroencephalographic changes, behavioral markers of sleepiness, changes in metabolite concentrations in exhaled breath and finger sweat, and correlation of metabolic changes among biological matrices.DiscussionThis is the first trial of its kind that investigates complete metabolic profiles combined with performance monitoring in humans over a multi-day period involving different sleep–wake schedules. Hereby, we aim to establish a candidate biomarker panel being indicative for sleepiness and its behavioral outcomes. To date, there are no robust and easily accessible biomarkers for the detection of sleepiness, even though the vast damage on society is well known. Thus, our findings will be of high value for many related disciplines.Trial registrationClinicalTrials.gov Identifier NCT05585515, released on 18.10.2022; Swiss National Clinical Trial Portal SNCTP000005089, registered on 12 August 2022.

What contributes to drug driving? An exploratory investigation into the influence of problematic substance use, roadside testing and alternative transport options

Despite a strong reliance on enforcement approaches to prevent drug driving in Australia, this behaviour is still prevalent. The objective of this study was to investigate the influence of problematic drug use (i.e., showing indications of addiction), exposure to roadside drug testing, the use of detection avoidance strategies, and perceptions relating to alternative transport options on drug driving among illicit drug users. A total of 1,541 licensed drivers from the states of Queensland, New South Wales, and Victoria completed an online survey. The survey collected demographic and problematic substance use information, as well as items assessing drug driving behaviour. Cannabis was reported to be the most commonly used drug (36.0%); the most common drug of problematic use (27.9%), and the drug most often taken prior to driving (43.5%). Observing police operating Roadside Drug Tests (RDT) was more common among the participants than being tested by RDT (35.7% vs 23%). The results indicated a significant association between being a drug driver and observing or being tested by RDT. The drug drivers were significantly more likely to report using a range of strategies to avoid police detection than the non-drug drivers. Similarly, the drug drivers reported that it was more difficult for them to use various alternative transport options than the non-drug drivers. Decision tree analyses found that significant predictors of self-reported drug driving were problematic drug use, holding a provisional or probationary licence, earning a low- or middle-income, and using detection avoidance strategies like remaining watchful for police vehicles and taking back streets. The findings of this study suggest that ongoing improvements to drug driving enforcement will need to be complemented by health-based approaches designed to reduce drug abuse and dependence, and improvements to public transport, in order to achieve a sustainable reduction in drug driving.

Rapid roadside drug testing in saliva using in vitro tongue

Rapid roadside drug testing in saliva using in vitro tongue

Driving under the influence of drugs (DUID) profiling in Spain: Data from oral fluid results between 2016 and 2022, including the effect of COVID-19 lockdown

To provide information about driving under the influence of drugs (DUID) cases in Spain during the last 6 years and to evaluate the impact of the Spanish lockdown (March 14th to May 6th 2020) on drivers’ consumption profile. In total, 16,461 oral fluid samples were collected from drivers in Spain that tested positive on the roadside between January 1st 2016 and April 15th 2022. Samples were collected at different locations throughout the country and analyzed by LC-MS/MS at the Toxicology Service of the Institute of Forensic Sciences of the University of Santiago de Compostela. For data analysis, drugs and their metabolites were classified in 8 different groups (cannabis, cocaine, amphetamines, opioids, benzodiazepines, ketamine, methadone and zolpidem). Demographic characteristics and drug profile were evaluated during time. The impact of COVID-19 pandemic lockdown was also considered, applying Chi 2 test. Drivers were mainly young adults (33.3 ± 9.9 years old) and men (94.2% male). In 97.6% of cases, LC-MS/MS results confirmed at least one of the positive results detected on the roadside. Cannabis (72.6%) and cocaine (64.4%) were the most detected drugs, followed by amphetamines (13.8%), opioids (12.9%), benzodiazepines (7.7%), and methadone (7.4%). Polydrug use was observed in 55.1% of drivers, being the combination of substances from two different groups the most prevalent. Cannabis and cocaine were the most common combination (either only the two of them or mixed with more substances). Changes in drivers’ consumption profile was noticed when comparing data from the specimens collected during the Spanish lockdown period ( n = 151) vs. specimens obtained during 2020 before (“pre-lockdown”, n = 557) and after (“post-lockdown”, n = 1974) that period. During the lockdown period drivers were 3 years older in average, and polyconsumers of 4 and 5 different groups of substances doubled (in average, 4.5% vs. 9.9% for 4 groups; 0.7% vs. 1.3% for 5 groups). Nevertheless, results were only statistically different for consumers of 4 groups of substances during lockdown, either compared with pre- and post-lockdown results. Also, for polyconsumers, the combination of cannabis and cocaine with amphetamines, with high prevalence before lockdown, was substituted by the combination of cannabis and cocaine with methadone. Furthermore, opiates use was two times higher (in average, 14.0% vs. 24.5%), being this difference statistically significant when comparing the 3 periods. On the other hand, amphetamines and ketamine were less consumed by drivers during lockdown (in average, 11.2% vs. 9.9% for amphetamines; 3.2% vs. 0.7% for ketamine). Nevertheless, these differences were only statistically significant when considering ketamine consumption post-lockdown (either compared with pre-lockdown or lockdown results). The use of oral fluid samples was able to confirm the vast majority of the screening results found in roadside screening tests. In Spain, cannabis and cocaine remain the most detected drugs on the roadside, as previously reported from our group in the period 2013–2015 (Lema-Atán JA. Drug Alcohol Depend 2019;195:106–113). During the lockdown period in Spain, due to stay-at-home orders, mobility was only allowed for “essential workers”. Samples collected in those months showed an increase in polydrug use, especially for opiates and methadone, as well as a decrease in the use of “party drugs” (amphetamines and ketamine). LC-MS/MS confirmation result was negative in only 2.4% of the cases. The DUID driver profile was a young man, consuming either cannabis or a combination of cannabis and cocaine, alone or combined with more substances. During lockdown, drivers consumed less “party drugs” and more opiates and methadone. Moreover, there was a higher rate of polyconsumers (4 or 5 groups of substances).

High resolution, high accuracy non-targeted LC-HR-MS/MS dried urine spot screening for drug of abuse testing

Screening for drugs of abuse in urine samples collected during roadside traffic testing is common practice in Switzerland. The use of an onsite rapid test for the detection of drugs and their metabolites is generally limited by a restricted panel of detectable drugs or substance classes (e.g. buprenorphine, benzodiazepines, cocaine, EDDP, morphine or opiates) with limited sensitivity and specificity. To improve the screening for legal and illegal drugs, the already collected urine sample typically undergoes an additional screening routine in a forensic laboratory. By using dried urine spots (DUS), sample handling, shipment, and storage could be substantially simplified, when compared to the sample handling of liquid urine. To prepare a DUS, the driver's urine is pipetted on a prepared paper card. The subsequent drying of the specimen, starting immediately after its collection, can prevent the post-sampling formation or degradation of substances (e.g. caused by bacteria). Furthermore, the DUS can be stored and shipped at ambient temperature and need no cooling or freezing. To evaluate the potential of DUS screening, 17 authentic urine samples containing multiple substances, were pipetted (10 μL) onto Autocollect TFN filter paper cards (Ahlstrom, France). After drying, the DUS cards were extracted (6 mm Ø extraction head) into glass vials with an insert (100 μL, methanol/water, 70/30, v/v), using a fully automated CAMAG DBS-MS 500 HCT autosampler in combination with a PAL RSI 3 robot. Subsequently, the prepared extracts were analyzed on a Sciex 5600 TOF instrument using a non-targeted screening and library searching approach. Thereby, 1 μL of the extract was injected onto a Kinetex C8 column and a ballistic gradient was used (mobile phase A: H2O+ 0.1% HCOOH, mobile phase b: MeCN + 0.1% HCOOH). A run time of 15 minutes was applied. To evaluate the performance of DUS, the screening results were compared to the analysis of the same urine sample in liquid form, using the same method on the same LC-MS instrument (injection of 1 μL of a 1/10 diluted urine). More than 50 different legal and illegal drugs were successfully identified within the investigated 17 urine samples using the DUS screening approach: 6-MAM, alprazolam, amoxicillin, amphetamine + metabolite, bisoprolol, bupropion + metabolite, caffeine + metabolites, carbamazepine + metabolites, citalopram + metabolite, cocaethylene, cocaine + BE + EME, codeine + metabolite, fentanyl, gabapentin, ketamine + metabolites, lacosamide, lamotrigine, levetiracetam, lidocaine, lorazepam + metabolite, losartan, metamizole-metabolites, metformin, methadone + EDDP, methylphendiate, metoclopramide, metoprolol, midazolam + metabolite, morphine + metabolite, nicotine + cotinine, ondansetron, oxazepam, paracetamol + metabolites, phenytoin, pregabalin + metabolite, promazine, propranolol, quetiapine + metabolites, sildenafil + metabolite, THC-COOH, torasemide, tramadol + metabolite, tranexamic acid, trazodone-metabolite, trimipramine + metabolites, venlafaxine-metabolite, zolpidem + metabolite. When compared to the analysis of liquid urine, the following compounds could not be identified: 2× nicotine, 1× promazine, 1× THC-COOH. Overall, 96% of the target substances that have been detected in liquid urine were identified correctly using the DUS approach. The DUS contain 10 μL of urine, therefore the signal intensity compared to liquid urine analysis, where we used 30 μL, is on average 68% lower. In most cases all substances were identified correctly using the DUS screening approach. Because of lower signal intensities for the DUS in one case of nicotine, promazine and THC-COOH were not properly identified. DUS Screening offers a simple, cost-effective and easier sample handling alternative to the traditional use of liquid urine. Based on the obtained results, a pilot study has been initiated (during roadside traffic control by the local police) in order to verify the usability in the forensic workflow.

Impact of vaping ethanol on the roadside field sobriety test in a clinical setting

Recent studies have shown that electronic cigarette (e-cig) liquid formulations (e-liquids) can contain ethanol, sometimes in concentrations greater than 20%. Ethanol, rarely listed as an ingredient in e-liquids, is often used as a thinning agent, to dissolve insoluble substances, or added intentionally for consumption. Ethanol in e-liquids has been demonstrated to be aerosolized by e-cigs. Ethanol within the aerosol can be absorbed across mucosal membranes in the mouth, and also within deep lung tissue based on mean-mass particle size diameter. Preliminary Breath Tests (PBT) and Evidentiary Breath Tests (EBT) are conducted to measure ethanol in exhaled breath, with a 15–20 minute wait period, and Standardized Field Sobriety Tests (SFST) evaluate several operant conditions to assess ethanol impairment. Literature on impacts of vaping ethanol is limited. An evaluation to assess the impact of vaping ethanol from e-liquids is essential for law enforcement officers (LEO), medical review officers, ethanol treatment and recovery providers, workplace drug testing, and court mandated drug testing. This study evaluated the impact of inhaled ethanol via vaping on the SFST, PBT, and EBT for thirteen participants using a blind two-by-two experimental design under Virginia Commonwealth University (VCU) IRB HM20015064 and in collaboration with the Virginia Department of Forensic Science, the Center for the Study of Tobacco Products at VCU, VCU Police Department, and City of Richmond Police Department. E-liquids were made by a commercial manufacturer at concentrations of 0% and 20% ethanol. Ethanol concentrations were verified in-house using a Shimadzu HS-20 headspace attached to a Nexis GC-2030 gas chromatograph with dual flame ionization detectors. Stability studies were performed monthly to ensure sample suitability prior to clinical use. Thirteen participants were enrolled into the study based on inclusion and exclusion criteria. They vaped either one or ten puffs of an e-liquid (0% or 20% ethanol). LEOs assessed indicators of impairment by following a study design incorporating SFSTs, PBTs, and EBTs at predetermined intervals. Ethanol concentrations within the e-liquids were determined to be stable at −20 °C for the duration of the study. Positive breath ethanol results ranged from 0.007–0.030 and 0.013–0.043 g/210 dL by PBT immediately after using a 20% ethanol e-liquid when vaping one-puff and ten-puffs, respectively. All subsequent PBTs were negative for ethanol. No ethanol or instrument error was detected by EBT for any vaping scenario, at any timepoint. Impairment was not indicated by SFST. A well-designed human clinical study with robust and relevant collaborations between a crime lab, police departments, and a research university is important to address pertinent questions to forensic science. Breath ethanol concentrations were detectable by PBT immediately after vaping an e-liquid containing 20% ethanol. The results demonstrated the standard wait period of 15–20 minutes employed by LEO before administering a PBT for roadside stops was effective in negating vaping-related false positive breath ethanol results. Vaping ethanol also did not impact SFST results. Results should be considered for other contexts of ethanol testing, such as workplace testing and vehicle ignition interlock systems.

Metabolomics for determination of non-substance related sleepiness

To date, there is no way to prove non-substance related sleepiness in a forensic context (e.g., after a traffic accident) although it is estimated that drowsy drivers cause 10-20% of all driving accidents. However, the legal situation is clear: the legislator prohibits overtired people from driving a vehicle in road traffic. An objective test for determination of non-substance related sleepiness is desirable. Metabolomics can offer a direct readout of one's phenotype. Changes in physiological functions (such as sleep-wake regulation) are reflected in endogenous metabolism and should therefore be detectable as changes in the metabolic profile, as an increase or decrease of specific metabolites correlating with hours of wakefulness. Our study aimed to assess the feasibility of discovering significant changes in the metabolome associated with hours of wakefulness. Saliva as easy-to-access samples should be used for these studies. Oral fluid samples of 13 volunteers were collected during a previous controlled sleep study that involved a sleep deprivation session and a control session in a randomized cross-over design. After a baseline night of 8 hours sleep, subjects were kept awake for 40 hours in the sleep deprivation session, whereas a 16/8 hours sleep scheme was applied during the control session. Six samples per participant were taken using Salivette® cotton swabs at defined time points across each study session during wakefulness after 0, 16, 25, 31, 38 and 40 hours, respectively. A seventh sample was taken after a recovery night that consisted of 8 hours sleep. Samples were processed using protein precipitation and dilution steps with acetonitrile and analyzed by UPLC-HRMS/MS (Sciex QTOF 6600, IDA) in an untargeted metabolomics setup. Both a reversed-phase (RP) and a hydrophilic liquid interaction (HILIC) column were used and both positive and negative ionization mode were measured to cover a wide range of metabolites. Our analyses detected numerous salivary metabolites in the presented setup (RP: 3845, HILIC: 2434), and many that underwent noticeable changes across the study time course. On the one hand, there are metabolites that increased or decreased in linear manner by hours of wakefulness during sleep deprivation but did not during control session with regular sleep regime. More importantly, some receded to baseline after recovery sleep. On the other hand, significant differences in metabolic profiles were apparent between sleep deprivation and control session. However, high inter-individual differences between study subjects impeded formulation of general statements. In addition to that, there were metabolites that followed a diurnal rhythm (i.e., circadian rhythm), like cortisol, arginine and tyrosine. We have shown that our untargeted metabolomics platform is in principle capable of analyzing salivary metabolites in sleep deprived and control subjects across a time course. Oral fluid is a rich and easily accessible matrix. Due to its simple and non-invasive sampling protocol, it is tailor-made for roadside testing and thus for forensic purposes. While rhythmically changing metabolites are not suitable to serve as marker substances for sleepiness due to their natural swings, those that show linear dynamics correlating with hours of wakefulness may serve as biomarkers. Nevertheless, identification of these remains tedious. However, several further considerations need to be addressed for a future optimized study. If not receding to baseline after recovery sleep, a metabolite cannot be related to sleepiness. High inter-individual differences come into play, too. Also, different sleep habits and therefore different sleep phenotypes are prevalent, resulting in time-shifted endogenous cycles that must be considered. Thus, a strict study protocol is needed for investigation of potential metabolic biomarkers for sleepiness to mitigate or eliminate confounding factors.

Affinity Assays for Cannabinoids Detection: Are They Amenable to On-Site Screening?

Roadside testing of illicit drugs such as tetrahydrocannabinol (THC) requires simple, rapid, and cost-effective methods. The need for non-invasive detection tools has led to the development of selective and sensitive platforms, able to detect phyto- and synthetic cannabinoids by means of their main metabolites in breath, saliva, and urine samples. One may estimate the time passed from drug exposure and the frequency of use by corroborating the detection results with pharmacokinetic data. In this review, we report on the current detection methods of cannabinoids in biofluids. Fluorescent, electrochemical, colorimetric, and magnetoresistive biosensors will be briefly overviewed, putting emphasis on the affinity formats amenable to on-site screening, with possible applications in roadside testing and anti-doping control.

Are Current Drug Driving Enforcement Strategies Achieving the Desired Effect? Drug Users’ Perceptions of Drug Driving Legislation and Enforcement in Queensland

This study examined how illicit drug users perceived roadside drug testing (RDT) in Queensland, a jurisdiction that enforces a zero-tolerance enforcement strategy to drug driving. Fifty-two illicit drug users were interviewed, and thematic analysis was used to identify emerging themes. The results showed that exposure to RDT and apprehension certainty were reportedly low. The targeted regime of RDT had dichotomous implications towards apprehension certainty, due to the familiarity with the testing procedures. Participants also reported mixed experiences with testing accuracy, in that some offenders reported testing negative just following use, while others who reportedly regulated their driving tested positive, despite not having recently used. Next, participants reported engaging in punishment avoidance behaviours that aimed to evade police exposure and suspicion, and to mask the presence of drugs in their saliva. The combination of avoidance behaviours and perceptions of one’s ability to circumnavigate RDT impacted on participants’ apprehension certainty. Due to their experiences, the majority of (cannabis) users agreed that RDT approaches were discriminatory and unjust, due to the zero-tolerance policy, the testing of presence over impairment, and the lack of policing towards other drugs. These perceived limitations were noted to potentially increase user offending in some circumstances and suggested that there may be a dissonance between the intended aim of RDT and the outcome on drug user behaviours. The findings of this study may hold implications for future research in identifying limitations in the current evidence and help inform policing procedures and policy surrounding future drug testing approaches.

Evaluation of an Increase in Roadside Drug Testing in Victoria Based on Models of the Crash Effects of Random and Targeted Roadside Tests

Drug driving continues to be overrepresented in both fatal and serious injury crashes in Victoria. As an enforcement countermeasure, preliminary oral fluid tests to detect drug driving were introduced in Victoria, Australia in December 2004. Recent research has modelled the relationships between prevalences of THC and methamphetamine in fatally and seriously injured drivers and (a) the annual numbers of random and targeted drug tests during 2010-2016 and (b) the positive detection rates from these tests. The increase in roadside drug tests in Victoria from 42,000 in 2013 (1% of licensed drivers) to 100,000 per year (2.2% of drivers), particularly targeted tests, is estimated to have saved 33 fatal crashes (13.7% reduction) and at least 80 serious injury crashes (1.4% reduction) per year. Based on the findings from this research, further increases in targeted and random roadside drug tests are warranted, up to at least 390,100 total tests per year, which are estimated to save a further 46 fatal crashes and at least a further 134 serious injury crashes per year.

Short-Term Traffic State Prediction Based on Mobile Edge Computing in V2X Communication

Real-time and reliable short-term traffic state prediction is one of the most critical technologies in intelligent transportation systems (ITS). However, the traffic state is generally perceived by single sensor in existing studies, which is difficult to satisfy the requirement of real-time prediction in complex traffic networks. In this paper, a short-term traffic prediction model based on complex neural network is proposed under the environment of vehicle-to-everything (V2X) communication systems. Firstly, a traffic perception system of multi-source sensors based on V2X communication is proposed and designed. A mobile edge computing (MEC)-assisted architecture is then introduced in a V2X network to facilitate perceptual and computational abilities of the system. Moreover, the graph convolutional network (GCN), the gated recurrent unit (GRU), and the soft-attention mechanism are combined to extract spatiotemporal features of traffic state and integrate them for future prediction. Finally, an intelligent roadside test platform is demonstrated for perception and computation of real-time traffic state. The comparison experiments show that the proposed method can significantly improve the prediction accuracy by comparing with the existing neural network models, which consider one of the spatiotemporal features. In particular, for comparison results of the traffic state prediction and the error value of root mean squared error (RMSE) is reduced by 39.53%, which is the greatest reduction in error occurrences by comparing with the GCN and GRU models in 5, 10, 15 and 30 min respectively.

Cost-Effective Foam-Based Colorimetric Sensor for Roadside Testing of Alcohol in Undiluted Saliva

A novel foam-based colorimetric alcohol sensor was developed for the detection of alcohol in saliva. Detection was based on the color change of a potassium dichromate-sulfuric acid solution absorbed by melamine foam. In the presence of alcohol, the orange colorimetric sensor changed color to brown, green and, ultimately, blue, depending on the concentration of alcohol in the sample. The response of the proposed sensor toward alcohol was linear from 0.10 to 2.5% v/v. The limit of detection was 0.03% v/v. Alcohol concentration could be determined using the naked eye in the range of 0.00 to 10% v/v. The developed alcohol sensor presented good operational accuracy (RSD = 0.30–1.90%, n = 8) and good stability for 21 days when stored at 25 °C and 75 days when stored at 4 °C. The results of alcohol detection with the developed sensor showed no significant difference from the results of spectrophotometric detection at a 95% confidence level (p > 0.05). The sensor was easy to use, small, inexpensive and portable, enabling drivers to accurately measure their own blood alcohol level and providing convenient speed in forensic applications.

Hit and miss: a comparison of targeted and randomised roadside drug testing (RDT)

PurposeThis study first aimed to investigate the differences in drug driver detection rates between a trial of randomised and targeted enforcement operations. The second aim was to identify which indicator categories are most commonly used by police to target drug drivers and to assess the effectiveness of targeted drug testing. Finally, this study aimed to quantify what specific indicators and cues (of the overarching categories) triggered their decision to drug test drivers and which indicators were most successful.Design/methodology/approachThis research examined the detection rates in a trial comparison of randomised and targeted roadside drug testing (RDT) operations as well as the methods utilised by police in the targeted operations to identify potential drug driving offenders.FindingsVisual appearance was by far the most commonly utilised indicator followed by age, police intelligence on prior charges, vehicle appearance and behavioural cues. However, the use of police intelligence was identified as the most successful indicator that correlated with positive oral fluid testing results. During the randomised RDT operations, 3.4% of all drivers who were tested yielded a positive roadside oral fluid result compared to 25.5% during targeted RDT operations.Research limitations/implicationsThe targeted RDT approach, while determined to be an effective detection methodology, limits the overall deterrent effect of roadside testing in a more general driving population, and the need for a balanced approach to ensure detection and deterrence is required. This study highlights that by focussing on night times for randomised RDT operations and the identified effective indicators for targeted operations, an effective balance of deterrence and detection could be achieved.Practical implicationsWhile the presence of a single indicator is not indicative of a drug driver, this study highlights for police which indicators currently used are more effective at detecting a drug driver. As a result, police could adapt current RDT procedures to focus on the presence of these indicators to support drug driver detection.Originality/valueThis is a world-first study that examines both randomised and targeted roadside drug testing. This study controls for location and time of day while using the same police unit for roadside testing, thus is able to make direct comparisons between the two methodologies to determine the effectiveness of police targeting for roadside drug testing. Furthermore, this study highlights which indicators used by police results in the highest rate of positive roadside drug tests.

A biomolecule-free electrochemical sensing approach based on a novel electrode modification technique: Detection of ultra-low concentration of Δ⁹-tetrahydrocannabinol in saliva by turning a sample analyte into a sensor analyte

Cannabis is currently one of the most consumed drugs in many countries. Δ⁹-tetrahydrocannabinol (THC) is the principal psychoactive component of this drug and is present in saliva after consumption. This paper reports a novel biomolecule-free electrochemical approach to detect an ultra-low level of THC in saliva using modified electrodes with molecules of the same analyte (THC) that are detected later via square wave voltammetry. The results from this research revealed that the electrodeposition of THC on the working electrode (sensor analyte) could highly enhance the limit of detection by improving the affinity of the THC molecules present in the sample (sample analyte) to the sensing electrode surface. Detailed descriptions about the optimization of the sensor and its performance in simple media, such as PBS, and complex media, such as simulated and real saliva, are provided. This novel and yet simple electrochemical-based sensing strategy allowed for a low limit of detection of 1.6 ng/mL THC in simulated and real saliva, distinguishing concentrations ranging from 2 to 25 ng/mL, making this technology viable for a real-world application such as roadside testing.

Dried Blood Spot in Toxicology: Current Knowledge

Dried Blood Spot (DBS) is becoming very popular in various medical fields, especially in toxicology. Nowadays it is commonly used in newborn screening for inherited or congenital diseases. This paperwork is based on a review of available literature. DBS is simple and rapid, it does not require trained medical staff to collect the samples. Specimens can be easily and safely transported to the laboratory. DBS provides an opportunity for roadside testing and rather quick results. Venous blood spot, collected from a finger or a heel, is put on the special paper card, which can result in a different distribution of blood and concentration of detecting substances. Marking multiple substances from one spot is extremely challenging, but due to further advancements in this area, it is only a matter of time until it becomes possible and all the disadvantages vanish. DBS is certain to develop and become even more worldwide used.