Drug Testing for Cannabis Orally
An absorbent collection device is placed in the mouth and the saliva collected is screened for drugs of abuse. Samples are checked to verify the saliva is human and undiluted
If saliva sample is tested in a lab, the detection level can be as low as 0.5 ng/mL (up to 72 hours after intake)
Unlike alcohol, for which impairment can be reasonably measured using a breathalyser (and confirmed with a blood alcohol content measurement), valid detection for cannabis is time-consuming, and tests cannot determine an approximate degree of impairment. The lack of suitable tests and agreed-upon intoxication levels is an issue in the legality of cannabis debate, especially regarding intoxicated driving.
The concentrations obtained from such analyses can often be helpful in distinguishing active use from passive exposure, elapsed time since use, and extent or duration of use.
The Duquenois-Levine test
is commonly used as a screening test in the field, but it cannot
definitively confirm the presence of cannabis, as a large range of
substances have been shown to give false positives.
Science and Research
2012 - Study ~ A
placebo-controlled study to assess Standardized Field Sobriety Tests
performance during alcohol and cannabis intoxication in heavy cannabis
users and accuracy of point of collection testing devices for detecting
THC in oral fluid.
2010 - Patent ~ # 7816143 Oral detection test for cannabinoid use.2010 - Study ~ Direct detection of Delta9-tetrahydrocannabinol in saliva using a novel homogeneous competitive immunoassay with fluorescence quenching.
2007 - Study - Interpretation of Oral Fluid Tests for Drugs of Abuse
2006 - Study ~ Drug Testing in Oral Fluid
An absorbent collection device is placed in the mouth and the saliva collected is screened for drugs of abuse. Samples are checked to verify the saliva is human and undiluted.
DRUG TESTING - ORAL & Cannabis studies completed
Portable Oral-Fluid Tests Still Unreliable For Pot, Study Says
June 12, 2008 - Ghent, Belgium
Ghent, Belgium: Saliva testing is neither a "practical" nor a "reliable" way for detecting the past use of cannabis, according to a scientific review published in the journal Therapeutic Drug Monitoring.
"Reliable point-of-care drug testing is still problematic, especially for cannabinoids and benzodiazepines," authors determined. "To date, there is no device that allows both reliable and practical point-of-care testing."
A 2007 review of ten oral fluid devices reached a similar conclusion. Of the ten devices tested, six recorded either false negative or false positive test results for marijuana's primary psychoactive compound THC. Five devices also recorded false positive results for the presence of marijuana's primary inactive metabolite, carboxy-THC (THC-COOH).
Previous evaluations of onsite oral fluid tests have also determined the technology to be unreliable for detecting recent cannabis use, particularly when administered at roadside checkpoints. Several European nations and a handful of US states are evaluating the use of such devices by law enforcement to identify motorists who may be driving under the influence of marijuana or other controlled substances.
For more information, please contact Paul Armentano, NORML Deputy Director, at: email@example.com. Full text of the study, "Current developments in drug testing in oral fluid," appears in the April issue of Therapeutic Drug Monitor.
updated: Jul 01, 2008
Interpretation of Oral Fluid Tests for Drugs of Abuse
Evaluation of on-site oral fluid screening using Drugwipe-5(+®), RapidSTAT(®) and Drug Test 5000(®) for the detection of drugs of abuse in drivers
|Wille SM, Samyn N, Ramírez-Fernández Mdel M, De Boeck G|
|Institution||Federal Public Service Justice, National Institute of Criminalistics and Criminology, Vilvoordsesteenweg 100, Brussels, Belgium. Sarah.Wille@just.fgov.be|
|Source||Forensic Sci Int 2010 May 20; 198(1-3):2-6.|
|Abstract||Driving under the influence of drugs is a major problem worldwide. At the moment, several countries have adopted a 'per se' legislation to address this problem. One of the key elements in the enforcement process is the possibility of rapid on-site screening tests to take immediate administrative measures. In this study, the reliability of three oral fluid screening devices (Mavand RapidSTAT, Securetec Drugwipe-5(+), and Dräger DrugTest 5000) was assessed by comparing their on-site results with confirmatory GC-MS plasma analysis. Our results demonstrate that for amphetamine screening, the oral fluid on-site devices on the market today are certainly sensitive enough. RapidSTAT, Drugwipe-5(+), and DrugTest 5000 demonstrated respectively a sensitivity of 93%, 100% and 92% for amphetamine/MDMA. For cocaine screening, sensitivities of 75%, 78% and 67% were obtained for the RapidSTAT, Drugwipe-5(+), and DrugTest 5000 devices, respectively. The studied devices were able to detect about 70% of all cannabis users in a roadside setting. However, a newer version of the DrugTest 5000 test cassette demonstrated a sensitivity of 93%, indicating an increased detection of Delta(9)-tetrahydrocannabinol using 'new generation' oral fluid screening tests with lowered cut-offs. Due to these promising results police officers and judicial experts are keen to use oral fluid screening devices. They believe that their ease of use and diminished amount of false positive results in comparison with urine screening will lead to more roadside tests and more appropriate juridical measures.|
|Pub Type(s)||Comparative Study|
Method For Detecting 23 Drugs And Medicines In Saliva Developed
ScienceDaily (Feb. 13, 2009) — A team of scientists from the Institute of Legal Medicine at the University of Santiago de Compostela (USC) has developed a technique for detecting the presence of 23 illicit drugs and medicines in saliva samples. The method, published in the journal Analytical and Bioanalytical Chemistry, is already being used by the DGT in Spain, as part of a European study on the frequency of alcohol and drug consumption amongst drivers.
"The saliva samples are collected by putting some cotton on the end of a special device placed under the tongue as if it were a lollipop, with an indicator that turns blue when there is a sufficient sample (0.5 millilitres)", so SINC was informed by Manuel López Rivadulla, one of the creators of the technique and researcher from the Institute of Legal Medicine at the USC. Each piece of cotton is then placed in a tube and labelled for analysis.
Rivadulla commented that when it is the traffic police who take samples from drivers, the tubes are placed in specially prepared containers and transported refrigerated to the laboratory. The saliva is therefore processed and analysed using two combined systems: liquid chromatography (LC), by means of which the molecules searched for are separated, and tandem mass spectrometry (MS/MS), which enables the "unmistakable" identification of the different chemical compounds.
This new method, which has been published in the journal Analytical and Bioanalytical Chemistry makes it possible to determine up to 23 substances in saliva at the same time, both illicit drugs (such as cocaine, cannabis and amphetamines) and medicinal drugs (morphine, methadone, codeine and diazepam).
The research group pointed out that drug and medicine detection in oral fluids is a non-intrusive technique, in contrast to blood or urine analyses. The individual can also be observed directly while taking the samples.
More than 3,000 drivers will be controlled
Rivadulla has informed SINC that this method is already being used for analysing saliva as part of a Directorate General of Traffic (DGT) study on the number of drivers that drive under the effects of psychoactive substances.
According to Juan Carlos González Luque, medical adviser at the DGT's National Observatory for Road Safety, the aim of the study is to determine the prevalence of the consumption of alcohol, other drugs and medicines amongst Spanish drivers. "Two samples will be taken during the controls: one will be analysed in situ, using rapid antigen-antibody immunological techniques, and another sent to the USC's laboratory in Galicia", he explained.
The taking of saliva samples began in September 2008 at 32 points around Spain (except the Canary Islands, Ceuta and Melilla). Those responsible for this initiative, which will finish in September 2009, aim to carry out this random selection control in 3,000 to 3,500 drivers.
González Luque added that the study has a dual aspect: legal and research. Legally, the relevant disciplinary penalties and punishments will be imposed on drivers in whom the presence of drugs is detected. "And we have already detected various cases", commented the DGT medical adviser.
But the main aim is to determine how many Spanish drivers consume both drugs and alcohol. The conclusions of the report will also help to improve the controls. González Luque intimated that it is highly likely that a simple and quick procedure will be ready this year which any traffic policeman can use.
Drugs a bigger problem than alcohol amongst drivers
The DGT adviser also warned that the information obtained to date indicates that drug consumption by drivers is an "even bigger problem than alcohol". The researcher highlighted that in 2007 the presence of psychoactive substances was detected in 10% of drivers who died on the road, without including the number of people who had an accident, were injured or died away from the scene of the accident, on whom no data is available.
This research forms part of the DRUID (Driving under the Influence of Drugs, Alcohol and Medicines) European project, involving 37 international research centres working in different lines.
In addition to the DGT and University of Santiago, the research work in Spain also includes the University of Valladolid, whose experts classify the drugs according to their effect on the ability to drive. This information could be of great help to doctors and pharmacists when it comes to giving prescriptions to drivers.
Roadside oral fluid testing: Comparison of the results of Drugwipe tests with laboratory
Pehrsson A, Gunnar T, Engblom C, Seppä H, Jama A, Lillsunde P
National Public Health Institute, Drug Research Unit, Mannerheimintie 166, FI-00300 Helsinki, Finland.
Drugged drivers pose a serious threat to other people in traffic as well as to themselves. Reliable oral fluid screening devices for on-site screening of drugged drivers would be both a useful and convenient means for traffic control. In this study we evaluated the appropriateness of Drugwipe 5 and Drugwipe Benzodiazepines oral fluid on-site tests for roadside drug screening. Drivers suspected of driving under the influence of drugs were screened with the Drugwipe tests. Oral fluid and whole blood samples were collected from the drivers and tested for amphetamine-type stimulant drugs, cannabis, opiates, cocaine and benzodiazepines by immunological methods, GC and GC-MS. The performance evaluations of the tests were made by comparing the results of the Drugwipe tests with laboratory GC-MS confirmation results of oral fluid or whole blood. In addition to the performance evaluations of the Drugwipe tests based on laboratory results, a questionnaire on the practical aspects of the tests was written for the police officers who performed the tests. The aim of the questionnaire was to obtain user comments on the practicality of the tests as well as the advantages and weak points of the tests. The results of the performance evaluations were: for oral fluid (sensitivity; specificity; accuracy) amphetamines (95.5%; 92.9%; 95.3%), cannabis (52.2%; 91.2%; 85.1%), cocaine (50.0%; 99.3%; 98.6%), opiates (100%; 95.8%; 95.9%), benzodiazepines (74.4%; 84.2%; 79.2%) and for whole blood accordingly, amphetamines (97.7%; 86.7%; 95.9%), cannabis (68.3%; 87.9%; 84.9%), cocaine (50.0%; 98.5%; 97.7%), opiates (87.5%; 96.9%; 96.6%) and benzodiazepines (66.7%; 87.0%; 74.4%). Although the Drugwipe 5 successfully detected amphetamine-type stimulant drugs and the police officers were quite pleased with the current features of the Drugwipe tests, improvements must still be made regarding the detection of cannabis and benzodiazepines.
Published 3 March 2008 in Forensic Sci Int, 175(2): 140-8.
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