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The use of LC–MS to detect Δ9-tetrahydrocannabinol (Δ9-THC) in oral fluid samples

Blowmonkey

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The use of LC–MS to detect Δ9-tetrahydrocannabinol (Δ9-THC) in oral fluid samples

Cannabis and driving: The use of LC–MS to detect Delta 9-tetrahydrocannabinol (Delta 9-THC) in oral fluid samples

Cannabis is the most widely used illicit drug in the world. There is strong evidence from performance studies that Δ9-THC has significant effects on the cognitive and psychomotor tasks associated with driving. New, easy and sensitive methods to detect impaired drivers are needed. Therefore, it is necessary the use of alternative biological samples which may be accurate, precise and with trustfully interpretation results. This article presents an LC–MS methodology for detecting Δ9-tetrahydrocannabinol (Δ9-THC) in oral fluid samples. The mean recovery was 79%, coefficients of variations were between 2.9% and 6.9% and the limits of detection (LOD) and quantitation (LOQ) were 1.0 ng/ml and 2.0 ng/ml, respectively. The method is sensitive, accurate and reproducible and may be utilized in ongoing controlled cannabinoid administration studies and in roadside studies and thus, important for the fields of forensic toxicology.

Helena Teixeiraa, b, , , Paula Proençaa, Alice Castanheiraa, Sónia Santosa, Manuel López-Rivadullac, Francisco Corte-Reala, b, Estela P. Marquesa, b and Duarte Nuno Vieiraa, b

aDelegation of Coimbra, National Institute of Legal Medicine, Coimbra, Portugal
bFaculty of Medicine, University of Coimbra, Coimbra, Portugal
cInstitute of Legal Medicine, University of Santiago de Compostela, Spain
http://www.sciencedirect.com/scienc...serid=10&md5=c2e8856281ab5566a86bc1f6a948f9da
 
Most pot smokers know that low amounts of herb in your system isn't going to hurt driving. You might drive slower, and be more cautious. Thats all. If you are stoned out of your mind, or even just stoned, better stay out of the front left side of that car (or right front for you europeans).

Oral fluid? Sounds like they are trying to sound all smart. Saliva, fucking geeks.
 
IMO ALL amounts of herb impair driving ability, it certainly doesn't enhance it; maybe make an exception for medicinal users. There is one study that shows low amounts of pot could possibly benefit people playing computer games, enhancing their abilities, but this can by no means be applied to driving a car.

About the study.. How are they going to measure the readings in chronic users, as I'm sure these people will show up with readings even after abstaining for several days?
 
Blowmonkey said:
IMO ALL amounts of herb impair driving ability, it certainly doesn't enhance it; maybe make an exception for medicinal users.
I know that when I used to drive while high, I had no "Road Rage" at all. Otherwise you could expect me to be cursing at someone on the road. Have I ever felt impaired while high? Yes, I would say about 3-4% of the time. Back on topic: I guess there will have to be a new definition of what is considered "high."

peace,
beta theory
 
"IMO ALL amounts of herb impair driving ability" I totally agree, it's not as bad as alcohol most of the time, but I'm not down with people smoking and driving, unless we're talking really small amounts.

How are they going to measure the readings in chronic users, as I'm sure these people will show up with readings even after abstaining for several days?

I'd hope they'd do something like: assume there is no such thing as tolerance, and that if your blood concentration is above Xng/mL then you're busted...
 
I think this'll just wind up as another tool to arrest more cannabis users.. Bah.

And I screwed up the title, could someone edit this so it reads "Delta" instead of "Δ"..?
 
"is one study that shows low amounts of pot could possibly benefit people playing computer games, enhancing their abilities, but this can by no means be applied to driving a car."

Ya, I rock at video games when stoned... but driving a car? My morals tell me no.

This'll be good to stop unecessary dangerous driving, but this will arrest many cannabis users.

How long does the 9-THC stay in the mouth? Few hours? Only when stoned? Few days?
 
The scary thing is that this technology is actually going to be implemented... in my town they've been trialling some THC/meth salival-detection swabs - that is, if/when you get pulled over and breathalysed, they'll ask you if you wanna participate in the test... you say yes, they'll swab your saliva and regardless of result let you go, after giving you $25 (presumably so you can go buy another foil..). The idea is to then use these at EVERY BREATHALYSER STATION in Aus, given of course that the things work.

If THC stays in the saliva as long as it does in say, fatty tissue, or urine samples, then shit, you smoke a spliff, get pulled over two weeks later and you're FUCKED. That's reason enough for the test to never even be used, AFAIC.
 
Well, they don't bust you for small amounts of breath alcohol, so I don't see why they'd bust you for small amounts of THC.
 
i smoke and i drive and i didnt crash anybody (yet *sarcastic smile*)
i crashed a curb just this morning when driving sober, so i dont know :)
but it's good to have a method to detect the amount of THC in oral fluid samples in case of an accident or something and who to blame.
 
ya i definately get in more accidents when im sober, about 90% (and i've crashed a lot). but i can agree with the computer games, im exceptionally better at chess when stoned, especially if i havnt smoked in a while, and i know that for a fact. music helps too tho, wow this is so off-topic. yes i do wonder how long thc remains in your saliva, and how accuracte the test actually is. could they tell if you smoked a whole 8th of schwag? or perhaps a couple hits of premium bud vs shit weed? what about other cannabinoids? could you hypothetically smoke weed that had no d9-thc (or miniscule levels) but other cannabinoids and pass the test?
 
What if you have dry mouth? ;)

http://www.oralfluidscreen.com/

No, but seriously, I believe that the issue with these saliva test kits is that they only return positive or negative results... so if a cop tests you and you show up positive for THC, doesn't MATTER if it was two weeks ago - you've got an illegal arrangement of carbon, hydrogen, and oxygen in your bloodstream and "you're coming with us son."

Would it to be economically viable to use sophisticated electronic devices designed to measure the specific levels of THC/metabolites and (meth)amphetamine/metabolites in the saliva and then convert the saliva reading into a useful full-body ?g/kg reading? No? Fuck no. So basically it's a greenlight, redlight situation, which is TOTALLY inadequate for dealing with the situation...

Then there are the potential problems of false positives in persons taking pseudoephedrine for nasal congestion or high-potency hydroalcoholic hops extract for insomnia (because I see a naturopath who tries to help me get away with positive THC tests ;) ) or the like...

Breathalysers were implemented because they were not only effective but rather CHEAP and easy to reliably use on a standardizable basis (potassium dichromate/EtOH reaction and associated absorption readings, considered against the average qty. of ethanol that is lost through breath/etc.).

So I could imagine if such technology is implemented on the roads in Australia (which more people should be allowed to die on anyways ;) ) then there will (or at least should) be NUMEROUS ways to twist it around...

By the way, just like to take the time to say that I fucking LOVE this new Advanced Drug Discussion forum... finally Bluelight's got a forum that's jam-packed with useful and interesting shit ONLY (as opposed to the "I scored like this capsule n shit so you guys better tell me how to have fun real fast or I'm gonna eat it n e wayz" posts that seem to be butt-banging the Psychedelic forum's credibility all the way to Analfissure St.). Keep up the good work dudes!
 
Yes, but after you show up positive for THC, they could take you for an evidential blood test, just like they do for alcohol.
 
BilZ0r said:
Yes, but after you show up positive for THC, they could take you for an evidential blood test, just like they do for alcohol.
If a suspect tests positive for alcohol, then he has been drinking in the very near past. If a suspect tests positive for THC, it is not very conclusive when he was smoking. If someone had been smoking a week or two ago, it seems like an awful waste of time and money to run blood tests.


peace,
beta theory
 
yes, but could such a blood test differentiate between a pot smoked 2 hours ago from pot smoked 2 weeks ago?
 
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