Topicals, Edibles and roadside drug tests

[billytheechidna]

Hi medical ozstoners, this a long post and not a simple question, but if you want to take time to read it, thanks in advance.

 

So, in this thread I was hoping to have a discussion about cannabis topicals (creams applied to the skin) edibles and, ahem…suppositories and how they may or may not show up on roadside drug tests used by Australian police (as distinct from smoked cannabis).

 

A bit of background to explain why I’m interested in this - I’ve never actually used cannabis myself in any form, but a while back I became curious about trying homemade topicals (like a coconut oil infusion) to see if they helped with chronic muscle pain, and as a general relaxant. So I started trying to find out everything I could and pretty soon the issue of drug tests came up. Many people say that topicals with THC aren’t psychoactive and won’t show on drug tests but others say they are or might – there just isn’t any solid research. I started to read anecdotal reports too about roadside drug tests here in Australia, including of how folks have tested positive many, many days after smoking, long after they were actually impaired. I was pretty alarmed by this, as I’m sure are many others, since losing my licence just isn’t an option. To be sure, I’ve had plenty of alcohol breath tests and never once been tested for drugs on the road, but all the same I need to be really, really confident that I would test clean if it did happen. (I’m not worried about urine and blood tests – I just don’t need to take these, but some people might in their workplace).

 

I wasn’t ready to give up on the idea, and curious besides, so I set about learning what I could about the parameters of saliva drug testing and the police regime here in Australia. In the process of finding out as much as I can about the current road drug testing regime and how it does or doesn’t work (and many of you would know that it is deeply flawed), I’ve found that there is actually very little research about how cannabis that is ingested or applied without being smoked is detected in saliva. Almost all the research and testing relates to cannabis that is smoked (which is after all how most people consume it). The current saliva tests seem to work primarily by detecting remnants of THC that remain in the oral cavity during smoking - and it may be these that can stick around for a long after the effects have worn off, potentially giving a positive result for a sober person. (This isn’t how the roadside tests are supposed to work – they’re supposed to show if you have been smoking very recently and therefore unfit to drive. But they are actually quite sensitive and especially if you are a regular smoker, you could have quite a bit of cannabis chemicals stored in your ‘oral mucosa’)

 

But…what if you had consumed cannabis extracts in another way, say eating it, swallowing a sealed capsule, rubbing it on your skin or using a suppository? (I presume injecting is a possibility, but I don’t think anyone outside a laboratory actually does that). I’ve tried to find out what I can, and although there is hardly any research it seems that strict blood to saliva transfer of THC may actually be quite low, possibly even undetectable by the current ‘Drugwipe’ tests, overly sensitive as they are.  This, I thought, was interesting…

 

Roadside testing.

Here’s what I understand currently happens in Victoria and NSW if you get pulled over or stopped at a booze/drug bus. I might be wrong in some details, so please correct me.

The test used first is the Securetec AG Drugwipe which you wipe on your tongue, and it shows a coloured line if positive. (There are different models that test for different numbers of drugs called 6S, 5S and Twinwipe, but with respect to thc they are all the same.) The latest Drugwipe brochure boasts that it can now detect THC in oral fluid at or above 5 nanograms per mL.  (Previously the cutoff point was 10 or 12ng). If you do test positive, they then double check your saliva sample in a Draeger 5000 drug test machine – this also has a cutoff point of 5ng/mL I believe.

 

I actually contacted Securetec AG and asked them about blood to saliva transfer and whether or not THC that was in the blood but hadn’t contacted the oral cavity could be detected by the Drugwipe tests. At first I got an answer to the effect that “if its in your system it’ll get into your saliva”; and then when I asked for more details or any studies that showed this I was basically told that they don’t share data like that with private busybodies. This could mean that its secret in-house research, or as I suspect that they also don’t know.

 

 

Studies

I tried to read all the published studies I could that were freely available on PubMed. There aren’t many that directly address the question of blood>saliva transfer and some were quite old. I’ve copied out a few salient quotes:

 

Schramm et al Drugs of Abuse in Saliva: A review Journal of Analytical Toxicology vol 16 Jan/Feb 1992

(20 and 16 are references to papers that I couldn’t get a free copy of, but if you read the original you can see the ref.list)

 

Radiolabelled ThC administered by intravenous injection cannot be detected in saliva (20). Therefore it seems that THC or its metabolites do not pass into saliva or lungs from the blood but rather are sequestered in the buccal cavity during smoking. In some cases cannabanoids may be detected in saliva for a longer time than in plasma (16) because it is sequestered in the mouth.

 

Milman et al, Oral Fluid and Plasma Cannabanoid Ratios after around the Clock Controlled Oral Delta 9 Tetrahydrocannabinol Administration, Clinical Chemistry 2011 Nov. 57(11)

In summary, our data demonstrate that THC detected in OF primarily reflects smoked cannabis, not oral administration…

 

(In this study they took regular smokers and gave them repeated doses of oral THC then measured their saliva and blood levels. They observed that Oral fluid levels were high before they started –possibly because the participants had smoked recently – but as the study went on, the oral fluid levels kept going down, to the point where they were almost zero, even though they still had high levels of THC in their blood.)

 

Huestis, M.  Human Cannabanoid Pharmacokinetics, Chem. Biodivers. 2007 Aug 4(6).

 

This one is all round interesting and talks about different administration routes and oral fluid testing.

 

Oral mucosa is exposed to high concentrations of THC during smoking, and serves as the source of THC found in oral fluid. Only minor amounts of drug and metabolites diffuse from the plasma into oral fluid. Following intravenous administration of radiolabeled THC, no radioactivity could be demonstrated in oral fluid. No measurable 11 OH THC or THC-COOH were found by GC/MS (detection limit 0.5 ng/mL) in oral fluid for 7days following cannabis smoking  (This suggests to me that these metabolites don’t pass from the blood to the saliva)

 

(I can’t resist sharing this quote too: Several different suppository formulations were evaluated in monkeys to determine the matrix that maximises bioavailability….That must have been an interesting day at the lab!)

 

 And lastly this study about edibles by the same author was in the news this year. http://www.jhunewsletter.com/2017/02/16/saliva-test-designed-to-identify-marijuana/

 

I haven’t read it except for the summary on science news sites, but it is actually really relevant. They wanted to find out if edibles, which are becoming more popular in legal MM US states, will show up on roadside saliva tests. They tested the Draeger 5000 and another similar device that had cutoff detection levels of 5ng/mL  and 25ng/mL respectively. They took previous smokers (whose mouths may not have been 1000% clean anyway) and gave them each a 50.6mg brownie. As I said I’m not experienced at all but that seems a fairly good dose.

Well, they found that THC could be accurately detected as positive in saliva, but only if the machines were set to a cutoff level much lower, around 1-2ng/mL. This suggests to me that those volunteers could conceivably have driven through an Australian drug test with the Drugwipe/Draeger, and not tested positive, even with fairly high levels in their blood.

 

I would never advocate driving high or drunk  - I want my family to be safe on the roads too, - but what I’m beginning to suspect is that edibles or topicals may be the way to go if you want to responsibly consume, can allow enough time to sober up properly, and hope to test clear at the roadside in following days. Of course if you rub thc oil around in your mouth or eat brownies like the cookie monster you would surely leave residues in your mouth which would show up. I suppose your best bet would be to swallow neatly with a glass of water. (Or make like a lab monkey.)

 

If only the Drugwipe tests were available cheaply enough for responsible people to test themselves before driving, but unfortunately they run at around $70 each! Even the police pay around $40 per test.

 

That’s what I’ve got so far – does anyone else have any thoughts, experiences or expertise? Please let me know what you think.

  

Regards, BillyE

[billytheechidna]

Ok, so an update. I got my hands on a copy of the last study I mentioned that was in the news in Feb this year. The full title is Cannabis Edibles: Blood and Oral Fluid Cannabinoid Pharmacokinetics and Evaluation of Oral Fluid Screening Devices for Predicting Delta 9 Tetrahydrocannabinol in Blood and Oral Fluid following Cannabis Brownie Administration. The lead author was Matthew N. Newmeyer. 

 

Basically this study was looking at how THC presents in blood and saliva after someone consumes an edible, and whether or not roadside screening devices can detect it.

 

They got a group of 16 volunteers to eat a brownie with 50.6mg of THC in it, and then they tested their blood and saliva over the next 48 hours. They use very sensitive lab tests as confirmation alongside the two roadside devices, the Draeger Drugtest 5000 (cutoff at 5ng/mL) and the Alere DDS2 (cutoff at 25ng/mL). The Draeger test is the one we are interested in because its the one used to confirm the result from the Drugwipe stick here in Australia.I say we're interested in the test, but really we're interested in knowing how long to wait before we will test clear.

 

They divided the group into 9 frequent smokers (most smoked daily) and 7 occasional smokers (2x per week). The frequent smokers had last smoked on average 9.5 hours before the test, whereas only one occasional smoker had smoked in the last 24 hours.

 

Basically, after accounting for the fact that the frequent smokers already had THC in their blood, the brownie dose affected the THC levels of all participants similarly (their blood and oral fluid levels, not subjective effects).

 

Here are some direct quotes from the bit about Oral Fluid Pharmacokinetics:

 

THC was detected in 5 (55.6%) frequent smokers (0.2-9.6ug/L) and no occasional smokers OF at baseline [before they ate brownies]

 

Peak OF THC concentrations were detected at first collection (0.33 hours) [20 min. The peak in blood came at between 1-3.5 hours for the frequent smokers and at between 1-5 hours]

 

THC was detected in frequent smokers' OF significantly longer ..than in occasional smokers'. At discharge (48h), 44.4% of frequent smokers were THC positive (0.3-2.6ug/L), while no occasional smoker was THC positive beyond 26h. [but that level is well below the Roadside DT cutoff]

 

With 1 and 2ug/L cutoffs, 100% of frequent smokers were THC-positive at 0.33h postdose, decreasing to 66.7% and 22.2% at 20h, and 11.1% (both cutoffs) at 48h, respectively; no occasional smoker was positive by 26h. With a 5ug/L cutoff, no frequent or occasional smoker was positive by 20 or 5h respectively.

 

So there is an interesting result. Remembering that 5ug/L = 5ng/mL, at that cutoff, 7 occasional smokers ate a 50.6mg brownie and after 5 hours, none tested positive in saliva (no mention of how impaired they looked or felt though.) 

For the frequent smokers it took much longer for all to test negative.

[billytheechidna]

So to summarize, the THC in oral fluid peaked at around 20 minutes after ingestion, then it went steadily down.

 

But the blood levels did not peak until between 1 and 5 hours later, then started to come down, meaning oral fluid THC was going down, even as blood levels were rising (!)

 

All the occasional smokers were clear of the 5ng/mL oral fluid test cutoff after 5 hours (but some may have been earlier). All the frequent smokers were clear of the 5ng/mL oral fluid test cutoff after 20 hours.

 

Another interesting thing to note is how high the peak in oral fluid was. For frequent smokers the median peak was 464ug/L with a range of (39.3 - 2111).

For occasional smokers the median peak was 392, with a range of (115 – 696).

Compare that to the peak in blood which ranged between 5.3-34.6ug/L for the frequent smokers and 3.2 - 14.3ug/L for the occasional smokers .

 

So what explains the wide ranges in the max OF THC and the difference between blood and saliva maxes? Was it previous smoking? Well, one of the occasional smokers had last smoked within 24 hours of the study beginning and all of the frequent smokers had too (with one particular guy having his last smoke only 40 minutes before going into the research facility. Poor dude probably needed to calm his nerves before eating a hash brownie for science! My money is on him being the one with the highest starting OF THC). However, as I said above, at baseline only half of frequent smokers and no occasional smokers tested positive in their OF.

 

I still think that oral contamination could be a big factor. The participants had 10 minutes to consume their brownie, and some may have chewed more than others, spreading the stuff around their mouths. I am just busting for someone to do a study on encapsulated THC to remove that variable!

 

Only 2 of the participants were women, aged 46 and 22 years. Both were in the occasional group. The rest were male between 19 – 40 years old.

 

This wasn’t a big or definitive study, but if you had to draw conclusions you could say that if you are a frequent male smoker who eats an 50mg edible, (and you refrain from smoking also), 20 hours is the minimum to wait to fall below the 5ng/mL cutoff.

If you are an occasional smoker (2x week or less) and you consume the same, you might be clear of the 5ng test after 5 hours – but, and this worries me, you might very well be at your most impaired around 5 hours as you experience your blood THC peak levels.

 

Now some people might think 50mg is a big dose, some a small one, but it is what it is. I’m also aware that in Australia one doesn’t stroll down to the dispensary to pick up edible products with THC% content neatly printed on the packet, but if you have some idea of the THC content of the strain you're using, you might be able to calculate roughly what your own edibles contain, and conservatively estimate THC and the time needed to sober up and test clear.  

[Sir PsychoHashy]

Thanks for posting that Billy E, some interesting stuff in there.

 

I think it's worth noting that in NSW at least, whilst in theory the Draeger machine is meant to be admissable in court blah blah, and if you pass it they let you drive away, if you sit the machine test because you failed the swab they send the swab off for lab testing.  Now it doesn't matter if it's a false positive or not, the testing they do aims to find the slightest trace, and if it does your busted, as Jester found out the hard way.  The law in NSW at least is very specific, it only requires you to have THC in your system, no matter how minor the level.  So relying on the settings on the Draeger to cover your arse based on the above info is not all you have to worry about.  This applies to all forms of consumption, so no matter how you do it there's an ongoing risk even if you know you're doing the right thing, which IMO sux big sweaty donkey balls.

 

Kinda hope that if our alleged medicinal cannabis legislation starts to become a reality, that they'll have to introduce a minimum level of THC in the blood for it to be an offence, but I'm not holding my breath.

 

[billytheechidna]

Hi Sir Psycho, I fully, fully agree about.....that thing with the donkey. What happened to Jester - was s/he let go and then charged later? 

 

I suppose I'm thinking that avoiding testing positive on the first screening is the goal, then you needn't be screened a second time on the Draeger.

 

The law in Vic is very similar. I did do some further research and had a chat with a courteous, helpful officer from Victoria Police highway patrol about what they currently do. He said that they used to use a machine similar to the Draeger, but no longer. He told me that in the case of a driver testing positive at the roadside, they would be taken back to the local station or drug bus for a second saliva test (with a similar test to the roadside swab. He was a little hazy on the details but kind of indicated that this involved putting a saliva sample in a solution of some kind, I'll see if i can confirm exactly what goes on). If the driver tested negative at the station, they would be free to go and not face future prosecution, however in all cases, both positive and negative, a saliva sample is sent to the Victorian Institute of Forensic Medicine for testing. He said that the police would receive a report indicating either that no THC was present, slight amounts, or that is was present; and only in the later case police would use this report to proceed with charges. He also indicated that unlike of roadside alcohol testing, a full certificate was not issued. 

 

I'll try to find out the details of what goes on at the Victorian Institute of Forensic Medicine and post here. 

 

Also I asked about how police decided who to test. He was quite upfront about the fact that the testing isn't random, or only partly so; for example, when they set up a drive though test site they might decided to test the first 8 people that come through for drugs, and after that they use their judgement, looking for obvious signs of impairment before drug testing. Slurred speech, unfocussed eyes etc. They get a positive result about 1 in12 times they test.

Out on the highway he said they wouldn't drug test everyone they stop, for example if they just pulled you over for a broken tail light. You'd always get breathalyzed though, which ties with my experience. Excessive speed (like 50+ over the limit) was a red flag for drug use, but I'd guess amphetamines usually. Really it was a pleasure talking to him, and when we were done he even wished me good luck with my paper or thesis!

Cheers, BillyE

 

 

  

 

 

[billytheechidna]

Another update with some new details.

 

So I was able to find out more about what Vic. Police use for RDTs- the first test on the roadside is the Securetec Drugwipe Twin, and if you test positive here, you get tested in the bus or at the station with the Securetec Drugwipe Twin Combo, which is essentially the same test again, only with the capacity to collect extra samples - one of which goes to the Forensic Institute and one of which you get to take away to have privately tested if you wish. 

 

The Drugwipe Twin or Twin Combo isn't for sale to the public, but it is apparently is basically the same as the Drugwipe 5S which you can buy. 

 

As to the cutoff level, the Securetec website claims 5ng per mL for their new 2016 model, but its a bit more complicated than that. The new test claims to test for both Delta 9 THC and 11 Hydroxy THC which is the liver metabolite. An expert in the area told me that it is almost impossible (without an electronic test like the Draeger 5000) to test below 10ng per mL for Delta 9 THC, but it would be possible to test for 11 Hydroxy THC down to 5ng, so by including substance this they can claim the 5ng - a bit of tricky marketing. 

 

According to the same expert, only a small amount of 11 OH THC returns to your saliva from the liver, around 5 to 25 percent. Now this information raises an interesting question: are the police using a new version of the Drugwipe Twin that also tests for 11 OH THC?  Or will they be supplied with them in the future, even unknowlingly? I don't know, but 11 OH THC is not one of the prohibited substances that the Road Safety Act specifies. It specifically states only Delta 9 THC, so I would think that a test sensitive to 11 OH THC would not be permissible under the Act.   

 

"prescribed illicit drug" means—

        (a)     methylamphetamine; or

        (ab)     3, 4-Methylenedioxy- N -Methylamphetamine (MDMA);

        (     delta-9-tetrahydrocannabinol;

 

It looks like 10ng per mL for Delta 9THC is the practical cutoff for the screening test - and the good news is that you can buy the Drugwipes to test yourself. The best price i can find is 49 dollars, which is the bad news. Nevertheless you're a regular smoker it might be worth buying a couple to see if you really are in the clear "the next morning". Be aware that dose and potency are apparently significant factors. 

 

Also, I've been reading more interesting studies which I'll give the details for here. You can google up free online copies if you're in to this sort of thing. But basically I'm finding more evidence that THC does not transfer from blood to saliva well enough to show on saliva tests, unless the mouth is contaminated. And if you do eat a brownie and get cannabis chocolate crumbs around your mouth, the levels fall pretty rapidly.  THCCOOH, the non psychoactive metabolite that stays in your system for a long time is another matter, but shouldn't be relevant for RDTs.

And for topicals, it seems even more unlikely that anything will reach your saliva. 

 

Vandrey R. et al, Pharmacokinetic Profile of Oral Cannabis in Humans: Blood and Oral Fluid Disposition and Relation to Pharmacodynamic Outcomes (2017)

 

Lee, D and Huestis, M, Current Knowledge on Cannabinoids in Oral Fluid (2014)

 

Milman, G. Cannabinoids and metabolites in expectorated oral fluid after 8 days of controlled around-the-clock oral THC administration (2013)

 

Lee, D., Can oral fluid cannabinoid testing monitor medication compliance and/or cannabis smoking during oral THC and oromucosal Sativex administration? (2014)

 

Swortwood, MJ., Cannabinoid disposition in oral fluid after controlled smoked, vapourized, and oral cannabis administration (2016)

 

 

Cheers, BillyEchidna

[wannagrowbuds]

Considering that THC is not soluble in water (and therefore I assume saliva) there must be something in the smoke bonding with the THC which leaves residue in the saliva.

 

Which brings me to the point, would somebody who only vapes test positive?

[billytheechidna]

Hi wannagrowbuds,

 

I think if you vape regularly, the best thing would be to experiment yourself. Buy one of the securetec drugwipe tests and test yourself, say in the morning before you usually drive off to work or whatever. If you do it would be really interesting to hear your results.

 

You're right about THC being essentially water-insoluble, which is probably part of why it isn't readily secreted in saliva. But I unfortunately, I think what's happening when you smoke or vape or consume edibles (unless it something like canna caps) is that THC is just physically deposited in your mouth. Just like whatever else you put in your mouth, traces get stuck in the folds and wrinkles of your tongue, between your teeth etc. It doesn't need to be dissolved in your saliva to carry over onto a swab, it just floats along with the rest of breakfast or last night's dinner. The studies where participants ate brownies showed a peak in oral fluid THC right after eating, for everyone, including the non-frequent smokers. My theory is that that's because they had some crumbs and oil from the cakes in their mouth.  In the study where they used encaspsulated THC, they didn't see the same peak in oral fluid. 

 

So in theory, the more often you put THC in your mouth, and the higher the potency, the more plentiful the deposits. A daily smoker/vaper is always going to have some in their mouth. What I'm thinking is that the best way to keep your mouth clean would be to make canna caps with an extract (like a coconut oil infusion). It sounds a bit over the top, but you could use a delayed release capsule so that it is delivered straight to your small intestine, and even carefully put the filled capsule inside another bigger clean one to make 100% sure you weren't getting any oil in your mouth. 

 

I had another thought today - if THC is readily soluble in oils and alcohol, then gargling and brushing your mouth with plain coconut oil or alcohol mouth wash would be more likely to remove deposited THC by dissolving it, vs rinsing and brushing with water, which is just a mechanical action. One of the studies I mentioned referred to substances that increased pH of oral fluid (like antacids) as interfering with saliva tests, so brushing your teeth with bicarb soda could be a helpful thing too.

Edited June 10, 2017 by billytheechidna

[jonny77666]

Hey mate. Would just like to thank you for going to great lengths to provide this information. I've read a lot over the past. Ethanol mouthwash, essential oil mouthwash, biotene, vinegar. All work in their own way. Swish some vinegar and notice 30 seconds later the amount of saliva in your mouth. Dilutes the sample, nothing to do with acidity, or how it's used to supposedly pass urine tests.

 

Anyway I signed up to thank you and point out we can possibly deduce the Police specifically still use the Drugwipe twin (over the 5s, 6s) solely due to the fact it doesn't detech 11 OH-THC! Whereas all the others do and therefore can't be used by Police.

 

I believe you are correct and 10mg/nl is their cutoff point, the 5ng/ml refers to the 11 oh-thc and is indeed a deceptive piece of marketing like you say. We can further deduce this to be the case if securetec currently have a test available in their brochure that doesn't test for 11 ohc, it would have to say 10ng. I bet the twin is the only one they still carry that doesn't test for 11 ohc and is thus 10ng not 5ng.

 

The twin are incredibly unreliable (false positives) and from what I've read the cut off is actually 20mg, unless they revised the twin in 2016 also (wouldn't it be called Twin II "S"?). It's hard to find any information on the twin as it's not available for public sale.

 

http://www.drugtesting.com.au/drugwipe.ht

Edited January 18, 2018 by jonny77666

[jonny77666]

Ok found in Victoria it's 20ng/ml the first test (twin), 10ng/ml for the twin combo, and the laboratory test only shows positive for thc (not 11 oh thc) in amounts 15ng/ml>

 

The only thing I'm unsure about whether the first test is 10 or 12ng but it's most likely 20ng.

 

They're relatively reasonable. Shouldn't get charged after 4hrs of a smoke. Which is around the time or not long after the high is completely gone.

Edited January 19, 2018 by jonny77666

[billytheechidna]

Hi Jonny, sorry i haven't checked on the thread in months. It's good to hear you found all this interesting. I still reckon 4 hrs after smoking might be pushing your luck (not to mention that we are probably always more impaired than we think) but a lot depends on individual variables. Like I said somewhere above, if you only smoke a joint once a week on Saturday night, then you ought to be ok on Monday morning, but if you smoke everyday, then the THC deposits in your mouth are going to build up and take longer to dissipate.

 

If anyone else is still reading this thread and driving within the law matters to you, I would again recommend buying one or more of the $50 drugwipe tests from an online store and testing yourself at least once to see how you go, because of all the individual factors. It has to be money well spent if it saves your licence.

 

If you are only consuming capsules then I think it is highly unlikely (even 'clinically shown') that the tests don't pick it up, regardless of how stoned you are, but if you use in a way that contaminates your mouth, like tinctures, infused fudges or canna-buttered toast, then the same advice would apply.    

 

Thanks for the response! Drive responsibly, y'all.