(Cannabis Consumption, THC Levels, Performance Impairment) "It is difficult to establish a relationship between a person's THC blood or plasma concentration and performance impairing effects. Concentrations of parent drug and metabolite are very dependent on pattern of use as well as dose. THC concentrations typically peak during the act of smoking, while peak 11-OH THC concentrations occur approximately 9-23 minutes after the start of smoking. Concentrations of both analytes decline rapidly and are often < 5 ng/mL at 3 hours.
Statistics and data relating to operating a vehicle while under the influence of an intoxicant (DUII), also referred to as drugged driving, drunk driving, driving under the influence (DUI), or driving under the influence of drugs (DUID).
(Motor Vehicle Accident Risk From Cannabis Use and Estimated Wait-Time Before Driving) "Cannabis use impairs cognitive, memory and psycho-motor performance in ways that may impair driving.10 Recent data suggest that approximately 5% of Canadian drivers/adults report driving after cannabis use in the past year.39 Large-scale epidemiological studies using different methodologies (e.g., retrospective epidemiological and case control studies) have found that cannabis use acutely increases the risk of motor vehicle accident (MVA) involvement and fatal
(Increased Risk of Motor Vehicle Accident (MVA) From Various Drugs) "We identified cohorts of individuals hospitalized in California from 1990 to 2005 with ICD-9 diagnoses of methamphetamine- (n = 74,170), alcohol- (n = 592,406), opioids- (n = 68,066), cannabis- (n = 47,048), cocaine- (n = 48,949), or polydrug-related disorders (n = 411,175), and these groups were followed for up to 16 years. Age-, sex-, and race-adjusted standardized mortality rates (SMRs) for deaths due to MVAs were generated in relation to the California general population.
(DRUID Project Evaluation of Oral Fluid (Saliva) Testing Devices for DUI Enforcement) "It is disturbing that the sensitivities of the cannabis and cocaine tests were all quite low, although further testing of the cocaine tests is desirable due to the low prevalences and the low concentrations encountered in this study. There are several countries in Central and Southern Europe for which these two substance classes are of special interest.
(Oral Fluid Test Evaluations for DUI Enforcement) "It is disturbing that the sensitivities of the cannabis and cocaine tests were all quite low, although further testing of the cocaine tests is desirable due to the low prevalences and the low concentrations encountered in this study. There are several countries in Central and Southern Europe for which these two substance classes are of special interest.
(Conclusions of the EU's Driving under the Influence of Drugs, Alcohol and Medicines (DRUID) Project) "The following conclusions can be drawn:
" It is advised to establish legal risk thresholds for illicit drugs on the basis of solid empirical data, i.e. experimental and epidemiological results. If the empirical basis is too weak, pharmacokinetic substance characteristics could help to define a lower effect limit.
" The risk thresholds for drugs should reflect the impairment equal to that of 0.5g/L BAC or to any other legally relevant BAC.
(Feasibility of DRUID Approach and of 0.5g/L BAC Risk Threshold) "Any threshold discussion should address the question if the DRUID approach to determine risk threshold as equivalents to 0.5g/L alcohol is feasible. From a scientific point of view it can only be justified to accept the same risk for all psychoactive substances (including alcohol). From a political point of view the determination of risk thresholds as equivalents to 0.5g/L alcohol might be questionable, because a BAC of 0.5g/L is not a legal limit in all European countries.
(Testing for Drug Use by Drivers) "Evidence-gathering technology for drugs is not as advanced in terms of ease of use and noninvasiveness as it is for alcohol. Until recently, no simple test police officers could administer to obtain an indication of drug use similar to the preliminary breath test for alcohol has been available. Rather, samples of urine or blood typically must be sent away for laboratory analysis to determine the presence of drugs and their quantification.
(Difference Between Drug and Alcohol Per Se Laws) "Drug per se laws are not quite analogous to the alcohol impaired-driving per se laws now in effect in every State make it illegal to operate a motor vehicle with a blood alcohol concentration (BAC) of .08 grams per deciliter or greater. Alcohol-impaired driving per se laws are based on evidence that all drivers are impaired at .08 BAC. Drug per se laws are more analogous to zero-tolerance laws that make it illegal to drive with certain drugs in the system."
(Prevalence and Trends in Alcohol Use by Drivers in the US) "The comparison of the BAC [Blood Alcohol Content] test results from the four NRS [National Roadside Survey] studies suggests that, during the most recent decade, there continues to be a downward trend in the proportion of drivers with positive BACs21 on U.S. roads on weekend nights, from 36.1 percent in 1973, 25.9 percent in 1986, 16.9 percent in 1996, to a low of 12.4 percent in 2007.