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Driving Under the Influence of Marijuana:

A Medical Evidence Based Perspective

TASA ID: 20522

Note: This webinar is approved for CLE credit in CA, IL, NJ, and PA.

Disclaimer: Please remember that if you are applying for CLE credit you must attend for the full 60 minutes of the LIVE presentation, not the ONDemand version. If a participant is seeking credit in states we are not approved to issue credit and the participating party seeking credit incurs a fee to receive said credit, it is not the obligation of TASA to remit payment for such credit. It is the participant's obligation to remit payment to the state in which they would like to receive credit.

On May 13, 2021, at 3:00 p.m. (ET), The TASA Group, in conjunction with medical cannabis expert Dr. Rachna Patel, presented a one-hour, interactive webinar presentation, Driving under the Influence of Marijuana: A Medical Evidence Based Perspective, for all legal professionals. During this presentation, Dr. Patel provided medical evidence-based answers to the following questions:

•             Does Marijuana actually impair ability to drive?

•             Is testing for THC (the main psychoactive substance in cannabis) a reliable means to measure impairment?

•             How does Marijuana affect psychomotor performance?

•             How does Marijuana affect driving performance?

•             Does the dose of Marijuana consumed matter?

•             Is there a correlation between THC blood levels and degree of impairment?

•             How to test for marijuana?

•             What are legal limits for marijuana?


About the Expert:

Dr. Rachna Patel has been practicing in the field of Cannabinoid Medicine since 2012. She step-by-step walks patients through how to use Cannabinoid products (Marijuana and Hemp based) for their specific medical condition(s).

Dr. Patel is a sought after expert witness, corporate consultant, professional speaker, and media correspondent.  She's sold over 27,000 copies of her book, The CBD Oil Solution: Treat Chronic Pain, Anxiety, Insomnia and more without the High. Dr. Patel also served as Chief Medical Officer of a CBD Products company.


Najah: Good afternoon and welcome to today's presentation, "Driving Under the Influence of Marijuana: A Medical Evidence-Based Perspective." The information presented by the expert is not to be used as legal advice and does not indicate a working relationship with the expert. All materials obtained from this presentation are merely for educational purposes and should not be used in a court of law, sans the expert's consent, i.e., a business relationship where she or he is hired for your particular case.

In today's webinar, Dr. Rachna Patel will answer the following questions. Does marijuana actually impair our ability to drive? Is testing for THC a reliable means to measure impairment? How does marijuana affect psychomotor performance? How does marijuana affect driving performance? Does the dose of marijuana consumed matter? Is there a correlation between THC blood levels and degree of impairment? How to test for marijuana? And what are legal limits for marijuana?

To give you a little background about our presenter, Dr. Rachna Patel has been practicing in the field of cannabinoid medicine since 2012. She step-by-step walks patients through how to use cannabinoid products for their specific medical conditions. Dr. Patel is a sought after expert witness, corporate consultant, professional speaker, and media correspondent. She sold over 27,000 copies of her book, "The CBD Oil Solution: Treat Chronic Pain, Anxiety, Insomnia, and More - without the High." Dr. Patel also serve as the Chief Medical Officer of a CBD products company.

Attendees who require a passcode for today, the word is CBD. During the Q&A session, we ask that you enter this passcode into the Q&A widget for CLE reporting purposes. The Q&A is located to the left of your screen.

Please remember that if you are applying for CLE credit, you must log on to your computer as yourself and stay for the full 60 minutes. You are also required to complete the survey at the end of the program. Please note that the CLE credit cannot be given to those watching together on a single computer. Tuesday morning, I will send out an email with a link to the archived recording of the webinar. The slides can be downloaded from the resource list at the widget at the bottom of your screen. Thank you all for attending. And, Dr. Patel, the presentation is now turned over to you.

Dr. Patel: Okay, Najah, thank you so much for that introduction. One thing I want to check in on is, as I'm clicking on the slides, can my audience see the slide that I've clicked on?

Najah: Yes. Well, did you just click on that next one?

Dr. Patel: Yeah, I just clicked on the title slide.

Najah: Okay. Yes, ma'am. We could see it.

Dr. Patel: Okay, perfect. Thank you. All right, so let's go ahead and dive right in. I'm gonna be talking about, as Najah mentioned, "Driving Under the Influence of Marijuana: The Medical Evidence Behind It." So what I'm gonna be going through is a list of questions, the list of questions that Najah mentioned, starting with two basic fundamental questions, legally, that this whole issue boils down to, and this was sort of a spoiler alert. But the first question is, does marijuana actually impair ability to drive? So basically, the long and short of it is, is that several studies have shown increased risk of impairment associated with cannabis use by drivers. However, other studies have not found increased risk of impairment.

The second question is, is testing for THC, the main psychoactive component of cannabis, a reliable means to measure impairment? And essentially, there are currently no reliable means to test or to measure whether a driver was actually impaired. All right, so moving on. How exactly does marijuana affect psychomotor performance? It's one of the main cognitive skills utilized while driving. So basically, the medical evidence shows that THC, specifically in the amount of 5 to 15 milligrams, can impair a variety of psychomotor functions as listed. Now, performance and all of these tasks deteriorate as the dose increases, and can last for two hours or more after the consumption of a single dose. And clearly these results have implications for performance in a variety of real life situations and across a range of occupations, including driving. So let's talk about that next. How exactly does marijuana affect driving performance?

So overall, long and short of it is, is that there are a number of driving-related skills that are impacted, and main skills that are impacted or that have been shown to be impacted are based on laboratory simulated studies in instrumented vehicles. Okay. So what we've found so far is that skills that are necessary for safe driving, such as slow reaction time, for instance, occurs. So this is, for instance, when someone is responding to an unexpected event, and they need to apply an emergency brake. Impairment under the influence of marijuana can also cause problems with road tracking. So we're talking about lane position variability, decrease divided attention, so target recognition. It can impair cognitive performance, so we're specifically talking about attention maintenance. It can also impair executive function, so route planning, decision making, and risk taking.

Now, what should be noted about the overall impact of marijuana on impairment, as far as we know, is that this is based on research that does not involve the measurement of blood THC levels. Rather, what's being done is that there's a comparison of subjects who have been given dose trials and non-dose trials, right. So essentially, under placebo conditions and non-placebo conditions. And as a result of this, what's been found is that there's a wide difference in blood THC levels between subjects. Okay, so I want to dive into a couple more specific studies when it comes to the impact of marijuana on driving performance. So a study published in 2010 compared the effects of three doses of cannabis on young, novice drivers and more experienced drivers. And the results of this simulated study showed that cannabis in general was associated with increases in speed and lateral position variability. And more specifically, results indicated that high dose cannabis was associated with decreased mean speed, increased mean and variability and headways, and longer reaction time.

Then a study published in 2015 looked at how blood THC concentrations relate to driving impairment. So this particular study didn't look at blood THC concentration, and results showed that cannabis increased standard deviations of lateral position. In other words, lane weave. And blood THC concentrations of 8.2 and 13.1 micrograms per liter during driving increased the standard deviations of lateral position, similar to 0.05 and 0.08 grams per 210 liters of breath alcohol concentrations, this is the most common legal alcohol limit.

Now, when cannabis was combined with alcohol, the effects were additive rather than synergistic. So with 5 micrograms per liter of THC plus 0.05 grams per 210 liters of alcohol showing similar standard deviations of lateral position, 2.08 grams per 210 liters of alcohol alone. And this is the next one I want to go over. Okay. And then finally, there was a study published in 2013 that evaluated the current literature on cannabis' effects on driving. And basically overall, the data showed that drivers attempt to compensate by driving more slowly after smoking cannabis, but control deteriorates with increasing task complexity. Cannabis smoking increases, as mentioned previously, lane weaving and impairs cognitive function. Critical-tracking tests, reaction time, divided-attention tasks, and lane-position variability all show cannabis-induced impairment. Okay. Now, here's the important point that I want to point out. Despite purported tolerance in frequent smokers, complex tasks still show impairment. And then finally, again, combining cannabis with alcohol enhances impairment, especially lane weaving.

All right, so the next question is, does the dose of marijuana consumed matter? So according to several sources of studies, driving performance decrements are generally dose related, and typically persist for two to four hours. All right. So, on a related note, is there a correlation between THC blood levels and degree of impairment? Okay, so this may be a little bit confusing because it's in direct contradiction to what I just mentioned, but I'll give you an explanation. So fewer studies have examined the relationship between THC blood levels and degree of impairment, as previously mentioned. However, in those studies that have been conducted, the consistent finding is that the level of THC in the blood and the degree of impairment do not appear to be closely related.

So peak impairment does not occur when THC concentration in the blood is at or near peak levels. Peak THC level can occur when low impairment is measured, and high impairment can be measured when THC level is low. Okay, so this has been in complete contrast to the situation with alcohol. All right. So why is it that there seems to be a correlation with the amount in milligrams of THC consumed, however, there doesn't seem to be a correlation between THC blood levels and degree of impairment. This is because the way that THC is processed in every individual is highly variable. It's unlike alcohol, which is processed at a very consistent rate in a very measurable way. That is not the case with THC. You can have 10 individuals in a room, all of whom consume the exact same dose in milligrams of THC, but then X amount of time later, if you take their THC blood levels, you'll find that the blood levels are highly variable amongst all kind of those individuals.

All right, now. Next, I'm gonna spend some time talking about standard field sobriety tests. Okay, so the question is, do standard field sobriety tests measure impairment? So a study published in 2005, and it was specifically conducted in Australia. So they assessed whether SFSTs is providing sensitive measure of impairment following the consumption of THC. Now in this particular study, 40 participants consumed cigarettes that contain either 0% THC, 1.74% THC, or 2.93% THC. What I want to point out here as a side note is that these percentages compared to what sold on the market are very low. On average, what you'll find in the cannabis market at dispensaries are cannabis cigarettes with concentrations upwards of 20% to 30%. So that is something to keep in mind. Now, for each condition after smoking a cigarette, participants perform the SFSTs on 3 occasions, 5 minutes, 55 minutes, and 105 minutes after the smoking procedure had been completed.

And the results revealed that there was, in fact, a positive relationship between the dose of THC administered and the number of participants classified as impaired based on the SFSTs. So more specifically, the results revealed that the higher the content of THC consumed, the greater the number of participants that were classified as impaired to a degree equivalent to a blood alcohol concentration above 0.10%. Now, consumption of cannabis containing either 1.74% THC or 2.93% THC did impair performance on the SFSTs. The level of THC in the blood related to the consumption of these levels of THC will range approximately between 2 nanograms per milliliter to 70 nanograms per milliliter. The results also revealed that the percentage of participants classified as impaired decreased from 5 minutes to 105 minutes after smoking. So overall, what they concluded was that the findings do, in fact, suggest that impaired performance on the SFSTs is related to the dose of THC administered. Overall, the findings indicate that the SFSTs provide a sensitive measure of impairment even when a relatively low dose of THC has been consumed.

Okay, so a similar study was conducted in 2005, also in Australia. Again, they were assessing the performance on SFSTs as a measure of impaired driving following the consumption of THC. Similar design study, they had 40 participants, they consumed cigarettes that contained either 0%, 1.74%, or 2.93% THC. For each condition after smoking a cigarette, participants performed the SFSTs on 3 occasions, again, after 5, 55, and 105 minutes. And in this particular case, they also underwent a simulated driving test on 2 occasions, 30 minutes and 80 minutes post-smoking cannabis. And in this case, the results showed that driving performance was not significantly impaired after 30 minutes post-consumption of THC, but was significantly impaired 80 minutes post-consumption of THC in both the low and high dose conditions. And when driving was impaired, a greater number of SFST signs were observed than when driving performance was not impaired.

Now, the percentage of participants whose driving performance was correctly classified as either impaired or not impaired based on the SFSTs range between 65.8% and 76.3% across the 2 THC conditions, okay. And the results, in this case, suggests that performance on the SFSTs provide a moderate predictor of driving impairment following the consumption of THC. And as such, SFSTs may provide an appropriate screening tool for authorities that wish to assess the driving capabilities of individuals suspected of being under the influence of a drug other than alcohol. All right. Now, within the United States, there was a study conducted by the National Institute of Justice. They supported researchers from RTI International. And in this case, they looked at how specifically cannabis dose and administration methods affect THC levels in the body, and also how that then correlates with performance on impairment tests.

So basically, overall, they concluded that THC levels in biofluid, okay, were not reliable indicators of marijuana intoxication. Many of the study participants had significantly decreased cognitive and psychomotor functioning, even when their blood, urine, and oral fluid contained low levels of THC. They also observed that the standardized field sobriety tests commonly used to detect driving under the influence of drugs or alcohol were not effective in detecting marijuana intoxication. All right, so let's talk a little bit about testing for marijuana, so I want to give you a broad overview. First and foremost, existing roadside drug tests cannot identify recent marijuana use. There is no chemical test for marijuana impairment like a blood alcohol concentration or breath alcohol concentration test. Toxicological test confirm the presence of THC, but they do not indicate driver impairment or necessarily indicate recent marijuana use.

The presence of THC in a driver, whether it's in blood, oral fluid, etc., does not establish impairment. It does not distinguish between active use of marijuana or environmental exposure or contamination. Some studies have shown that people exposed to secondhand marijuana smoke can, in fact, test positive for THC. All right, so, next I'm gonna talk about screening for marijuana as well as specimen testing for marijuana. But overall, when it comes to screening for marijuana, it's common to use an immunoassay test designed to detect cannabinoids. However, what's important to know here is that a positive screening test cannot be taken as evidence that the drug is present in a specimen. Because these tests lack high specificity, and they're subject to cross reactivity and may, on occasion, produce a false positive result.

Many of the THC amino acid screening tests can give a positive response to the presence of THC metabolites, even though THC is not present in the sample. All right, next, let's talk about specimen testing for marijuana. So starting with blood, THC level in blood or oral fluid does not appear to be an accurate and reliable predictor of impairment from THC. Low THC levels of a few nanograms per milliliter in blood can result from relatively recent use, so smoking within one to three hours, or it can result from chronic use, where no recent ingestion has occurred and no impairment is present. When it comes to oral fluids, so there are some companies out there that are marketing self-contained kits that are used by law enforcement. However, these point-of-arrest screening devices have not been shown to be completely accurate and reliable.

Marijuana, so THC is readily detected in oral fluid. However, there are issues associated with distinguishing use versus environmental exposure that haven't really been fully addressed. And then finally, when it comes to hair, THC can be detected in here. But it can, again, it can result from environmental exposure. And that can result in a positive hair test result as well. And then finally, what are the legal limits for marijuana? So they vary from state-to-state. And they can vary anywhere from zero tolerance law, which is what you see in blue, in orange, you see per se law, in gray is under the influence, so DUID, and then in green, it's permissible influence law. And this only applies in the State of Colorado. And basically in that state, it applies if THC is identified in your driver's blood in quantities of 5 nanograms per milliliter or higher. So that, in a nutshell, is driving while under the influence, the medical evidence. At this point, I am more than happy to take questions.

Najah: If everyone could type the passcode into the Q&A widget, the passcode is CBD, in addition to typing your questions in. Dr. Patel, I did load you up with one question in the chat already.

Dr. Patel: Okay. The question is, what is the effect of drinking alcohol below legal limit while using marijuana? Okay. So medically, in terms of research, most of the research that's been done on this comes from pilot studies. So these are small scale studies. In one particular study that was done, what they found was that when an individual consumes, let's just say, 1 or 2 glasses of wine, and we'll assume that falls below the legal limit, it wasn't specifically indicated in the study, but let's just assume.

And so when these individuals consumed about 1 or 2 glasses of wine, and then along with it consumed cannabinoids, what they found was that the levels of cannabinoids stayed elevated in the system longer than the alcohol did. And what may be going on is that the alcohol is being processed before the cannabinoids are being processed. It is essentially the body prioritizes what's the more toxic substance that I have to get out of the body. And so that's maybe something that's going on. And like I mentioned in one of the studies, the effects are additive rather than synergistic when cannabis is combined with alcohol. Hopefully that helps to answer that question. We have a comment. Good luck finding anything in dispensaries with 2.93% THC. Everything is between 10% and 33% THC now. Correct, like I mentioned, what they used in the study was far below what's available in dispensaries nowadays. Like I mentioned, it's upwards of 20% to 30% is what you'll find.

Okay, site to access the Australian study of things. Sure. So let me just go back to my slides. Najah, does the audience have access to the slides? Because I've listed the sources at the bottom.

Najah: They do. Yeah, they do have access. I'm gonna give it to them.

Dr. Patel: Great. So if you look at the slide, I do link out to the source. And that's where you'll be able to access the original study. Any other questions that came up while I was going through the presentation?

Najah: Yeah, I just sent you one.

Dr. Patel: Okay, great. How much of a difference is there between ingesting of smoking before the effects hit a person's system? Okay, this is a great question. Scientifically, it comes down to onset of action, okay. And based on medical research, medical studies, when it comes to inhalation, it takes effect between seconds to minutes. So at most, we're talking about 5 to 10 minutes. However, when it comes to ingestion, it takes up to two hours. Now, there's a common misconception here that it's going to take, for whatever reason people believe it's only gonna take 20 minutes for an edible to take effect. And so what they end up doing is that they'll consume the edible but they'll wait 20 minutes, and they won't feel an effect. So they'll make the mistake of then consuming additional edibles, okay. Now, by the time the two hours hitch, they've, essentially, consumed a toxic dose, and they're going to experience gnarly side effects at this point in time. So, hopefully that helps to answer that question.

Question number four, what does the future look like in regards to testing for DUI regarding THC? Here's the thing. If this science behind THC is tricky, okay. It's not like alcohol, alcohol is water-soluble, it gets processed at a very consistently, like I said, it's measurable. THC is fat-soluble, it gets stored in the fat cells in your body. Now, as we all know, we all process that differently. Some of us tend to hold on to it tighter, some of us tend to let go of it easier. And so because it gets stored in the fat cells in your body, as you break down these fat cells, the THC gets released into your bloodstream, right, making it detectable in drug tests. So that's the tricky thing. I mean, at this point, we're able to detect presence or absence of THC. But what we don't know yet and what the tricky part of it is, well, how far back was the consumption? Right. It can go back, gosh, 90 days even. And that's not necessarily gonna lead to impairment 90 days later. So that's the tricky part. And that's the science that we're trying to figure out at this point.

Okay, next question is, how much... Oh, I already answered that question. Dabs and oils now contain upwards of 90% THC, how does that impact impairment? Okay, this is a great question. So basically, dabs and oils are typically inhaled. Right? So let's just say someone inhales like they did in this study, 1.74% THC. One puff, and it's a certain amount of 1.74% THC, then you have another person that inhaled similar amount, but it's 90%. Okay, so you're already getting a greater number of THC molecules in that 90% puff versus a 1.74% puff. And then, because you have more molecules, you have more molecules surrounding the receptors, and it's interacting with more receptors. Okay. Because it's inhaled, it's still gonna take 5 to 10 minutes, let's just say at most 5 to 10 minutes to take effect. But in terms of impairment, you may get to a higher blood level as opposed to...with 90% than 1.74%. And as the data shows, you can potentially...potentially, t can impair you more when there's a higher amount consumed.

Okay, next question. Your presentation related to low doses of THC, what is your reaction to the impairment of an operator with levels of... I don't have the rest of the question.

Najah: Hold on, I'm trying to find it.

Dr. Patel: Okay.

Najah: Richard, if you can finish that question for me. I'll go to the next one. But I'll make sure that we answer your question as well. All right, I'm sending the next one over.

Dr. Patel: Okay. Oh, this is a good question. Okay. So if you are an expert for the defense, what would be the top three things you would look to in order to challenge the findings of impairment? Okay. I mean, mainly, first and foremost, when it comes to the test itself, yeah, you can detect, like I mentioned, detect the presence or absence of THC. But we don't know how far back that consumption goes. Right. So that's one thing. The other thing is that, at this point in time in terms of amount consumed, there's no correlation, in terms of blood levels, there is no correlation. So there's no consensus within the medical community in terms of amount consumed or blood levels, in terms of...in actually having an effect on impairment.

Okay, so this is a legal question. Is smell of marijuana probable cause to search a vehicle? From what I've read, it is, however, I'm a physician, I'm a medical expert. So I'm going to leave this to the legal experts that are actually viewing this presentation to help accurately answer this question.

Najah: I just put in the completion to question number seven.

Dr. Patel: Sure. Okay. So let's start from the top. Your presentation related to low doses of THC, what is your reaction to the impairment of an operator with levels of...impairment effect of blood tests at a level of 35 nanograms per milliliter? Okay, so, again, there is no correlation when it comes to blood levels, and this just tells me that there was a presence of THC, but I don't know when this person consumed. It could have been within the last 24 hours. Like I said, it could have been all the way back to, like, 90 days. And so all this tells me is that there was presence of THC. It does nothing... I can draw no conclusions about the impact that it has on impairment. Okay, so next question is, why is marijuana impairment not... Apparently, I'm assuming this is dose related. Okay. So, this boils down to how THC is processed in the body. The first of which that I mentioned, which is that THC gets stored in the fat cells in the body, right. And fat cells we hold on to for a while, and they break down little at a time. And as they break down, they release the THC into the bloodstream. And so that's one, right.

The second thing is, is that the machinery that we have in our liver known as cytochrome P450, they're genetically from person-to-person. And this is what breaks down cannabinoids, like CBD, like THC. And so some people's machinery works faster, some people's machinery works slower. What's also impacted is potentially...the machinery is also impacted by other substances or other medications or other drugs that they may have in their system. Because this machine can only process so many substances or drugs or medications at a time, as in the example that I gave with a study that was done when these people consumed a couple glasses of wine along with cannabinoids, what they found was that the body processed the alcohol before it processed the cannabinoids, and so the amount of cannabinoids stayed elevated for far longer than it would if it was just taken on its own.

Okay, are there any neurological tests available to determine a quantitative impairment of psychomotor function? Yes, there are. So basically, when we're testing for strokes, we are looking at a psychomotor function, and there are neurological tests that we have patients go through. Okay, so this next question is CBD. There are claims on the part of breathalyzer companies for marijuana that they can detect both inhaled or edible forms of THC, okay. I've identified inhaled but have not yet found any indication breath can pick up edible because of lipid binding, breath hydro. Okay, I don't know if that's the name of the company. Okay. I'm not sure what the question is. But yes. Just to reiterate what you said, yes, there are companies out there that... So as I mentioned, THC can be detected in oral fluids, right, so we're talking about like saliva.

And potentially, if a person's consumed an edible, it can be detected, like if it's a hard candy that they leave in their mouth for a while. Some of the cannabinoids can get left behind and be detected that way. If it's like a chocolate, and they swallow it pretty quickly, then there's a chance there that cannabinoids may or may not get left behind in a sufficient enough of a quantity to get detected. So hopefully that adds to the information that you have there. How many states are using point-of-arrest kits to adduce THC levels of drivers? I'm actually not sure how many states are utilizing these sort of kits.

Does California has a road roadside...any test for roadside testing? Not that I know of. I know that there's a company in California known as Hound Labs that's working on creating the equivalent of a breathalyzer for cannabinoids. But that's as far as I know, in terms of what's being done. Has an actual kit been implemented by law enforcement? Not that I know of. I'm not certain about that.

Okay, next question. How much of a difference is there between ingesting and smoking before the effects hit a person's system? Okay. So this has to do with a couple of different factors, potency of the product, amount that they're consuming, and then, like I said, onset of action. Onset of action is fixed, typically. So onset of action with anything that's ingested, like I mentioned before, will take up to two hours. And with inhalation will take up to 5 to 10 minutes. What's gonna be variable there when it comes to ingestion is the potency of the product. If it's an edible, what is the total milligrams of the product? And then of those total milligrams, how many milligrams do they actually consume? And then same with smoking, what is the potency? And then this is less measurable, how much they consumed when it comes to inhalation.

So those are the factors that will come into play when it comes to how long it's gonna take for the effect to hit. Like let's just say, for example, they take half a milligram of THC, for some people, that may have no effect at all. But for other people, it may get to the point... Typically the psychoactive effect of THC, a pure THC product starts to hit between 10 to 15 milligrams. Okay. However, having said that, that's an average, for some people out there, they can consume 25 milligrams and they may, from that, experience psychoactive effects. Is the only test for driving under the influence of marijuana the observation of the officer? I imagine that varies from state-to-state in terms of what the specific local law enforcement has decided.

Okay, if someone is driving under the influence of both alcohol and marijuana, is there a known study apportion the nexus? No, there's no consensus when it comes to actual numbers leading to impairment when both alcohol and marijuana are combined. Okay, how do edibles compare to smoking with regard to blood level and impairment? Okay. So it's gonna vary, it's gonna vary from person-to-person. Again, it's gonna vary based on the potency of the product and also on how much they have consumed.

And also, like I mentioned before blood levels are going to vary as well. Okay, let's see. Okay, so please explain the difference between additive versus synergistic. Okay. So additive is essentially, one, the effect of one chemical adds to the other. Synergistic is they're both working together to create an effect. So it may not necessarily be that the parts lead to a sum, it may be less than the sum, whereas an additive effect the parts you lead to the sum. Let me know if that simplifies that for you. If not, I'll try to explain it another way. Typically, how does the prosecution prove a DUI marijuana case? Again, this is more along the lines of a legal question. So I'm not certain. I know it would be easier for the defense because, like I mentioned, when it comes to testing, you can detect the presence. But you can't really detect how far back that presence goes. How long does marijuana remain in the bloodstream? A single dose has been found to remain in the body for up to 72 days. And that's a single dose. So it could be longer, because most people typically consume more than a single dose.

Let's see. Somebody wrote. So essentially, there is no accurate test that establishes being under the influence. No, there's nothing on the market out there, like a breathalyzer for alcohol. Does THC level in the blood increase by eating rather than smoking? It can increase in both ways. Again, it comes down to potency and amount consumed. Okay, I'm not sure, I think this might be a question for you. How will you know to email us our certificates with our assignment sheet?

Najah: It is. It is Thank you.

Dr. Patel: Okay, oh, this was a great question. Okay. So is there a difference between delta 8 and delta 9 THC in terms of detection and impairments? Okay. So first and foremost, delta 8 and delta 9 are completely different molecules. They are mirror images of each other. And what is the significance of a molecule being a mirror image when it comes to biochemistry, it interacts with the receptors in different ways. As far as we know, the medical data shows that delta 8 is not psychoactive.

And so it should not have any impact on psychomotor function either, as far as we know. That's also the case of CBD. Medical data has shown that CBD does not have an impact on psychomotor function. And also when it comes to detection, okay, so the tests that are run, they're not actually detecting THC. What they're detecting is breakdown products of THC. Okay, so that was one of the other facts that I mentioned, that you can detect the breakdown product of THC in the blood, but then there's no actual THC present in the blood. Okay, so that's important to know. My book is available on Amazon. You can just do a Google search for "The CBD Oil Solutions." In it I go over a couple different things, the basics of cannabinoids, so THC and CBD, the biochemistry of it. I go into how CBD products are made, the nuances of that, how to use CBD products, whose CBD products are effective for which medical conditions.

Okay, what is considered a single dose that remains in the body for up to 72 days? I'm gonna have to go back to that study. But they did specify in that study what they considered a single dose. And in that specific study, it was an inhaled dose. So I will have to get back to you on that one. Do regular users develop a tolerance? Yes, they can potentially develop a tolerance, whereby the more and more they take, they're not experiencing the same level of medical benefits. And because they're consuming so much, they may be likely to also experience side effects as well. This is where the whole situation with what's known as cannabinoid hyperemesis syndrome comes into play, where usually THC helps nausea and vomiting. But if you consume too much, it's gonna cause nausea and vomiting.

Okay, so a blood test of someone that smokes marijuana and then drives will only show the presence of marijuana, not the level. It will show the level. It will show the presence and it will show the level. However, there are no conclusions that can be deduced in regards to impairment based on the presence or the level. Because, like I said, the presence could have been...the person could have consumed 30 days ago, and the THC gets stored in the fat cells in the body. And over time it gets released. But 30 days later, they will be able to potentially just have the THC. And it may show at a certain level. But we can't draw any conclusions in regards to the effect that is has on impairment.

So the blood tests don't actually measure the amount of nanograms in a person's blood? They do. They do. Yeah. I'm not sure if I misspoke during the presentation. And there was a misunderstanding of that. In PA, is there a rule for driving under the influence? Yeah, so let's take a look at this map here. So Pennsylvania has per se laws in place, where the law prohibits driving with a detectable amount of THC in the body that exceeds the legal limits. And I'm not sure what that legal limit is specifically in Pennsylvania. Can metabolites of marijuana be smelled? Local officers here claim they smell metabolites of alcohol, wonder if this thing would be possible for marijuana. No. So the smell of marijuana actually comes from a group of chemicals known as terpenes. So terpenes include chemicals such as linalool, limonene, humulene, caryophyllene, these same chemicals can be found in fruits like lemons. Limonene is found in lemon and it gives it that lemony smell, and there are strains of marijuana that have a citrusy smell because it has higher amounts of limonene. So what you smell, that distinct smell of marijuana comes from terpenes.

This is a comment, not a question. There are functional tests ready for roadside, we have one testing retina and there are two measures of brainwaves, but required to do clinical FDA studies. And these are illegal in USA. So big catch 21. Okay, I think I've heard of this. And what I like to always go off of is based on, like, solid medical evidence. So there's still clinical studies yet to be done on this.

Najah: I think we've asked all the questions.

Dr. Patel: Yeah, these were some great questions. It seems like next time around, I should focus more on the specifics of cannabinoid testing when it comes to all the specific specimens.

Najah: I'm sorry, I think there was another one that came in. Okay, a couple others.

Dr. Patel: Okay, do the metabolites in blood fluid test require carboxylation to 11 delta hydroxy THC for detection? Yes. So it's typically 11 delta hydroxy THC that is metabolite that is tested for.

Najah: Could everyone type the passcode in, please, while I continue on giving these questions about the fatalities [SP]?

Dr. Patel: Is the use of perceived levels of THC to determine guilt scientifically supportable? Oh, it's gonna... I mean, this would be a combination of like putting a lawyer and a physician's brains together. So I would say when you get in touch with me, and if this is surrounding a specific case, we can discuss it further. Okay. Now, this question says, "So, though law state you can't drive with certain levels of marijuana in the system, the studies indicate that the level doesn't really correspond to impairment." Correct. Correct. And this number that they've come up with in Colorado is essentially arbitrary. In Colorado, they have permissible inference law, applies with THC by identifying in a driver's blood in quantities of five nanograms per milliliter or higher. If so, it is permissible to assume that the driver was under the influence. Yeah, this is completely arbitrary. There's no medical data to support this number.

Does horizontal gaze nystagmus test detect marijuana? There is shown to be a correlation. But you can't assume that just because the horizontal gaze nystagmus test is present that the person is under the influence of marijuana. Also correlation, but not causation.

Najah: Okay, so those were all the... These questions. Thanks, everyone, for these questions. I love them. I just found one...

Dr. Patel: Client is on probation and tests positive for marijuana, what are the best arguments that the result is a false positive? Gosh, okay, so this is gonna get dependent. Was it a screening test? What type of test was it? Was it an immunoassay test? Or was it a specimen test of blood, of oral fluids, of hair? I'll need some more details there.

Najah: We can follow up with that question via email. So I'll send you over the individual's name and contact information.

Dr. Patel: Yeah, and you guys, there's some specific questions here. You can always reach out to me on my email, drrachnapatel@gmail.com. These are some great questions that have come in. I wish I had more definitive answers for you. But clearly, the medical evidence, like I said before, when I gave away the spoiler, it is lacking at this point in time. Okay, so our drug recognition evaluation is medically supported. There's research indicating is that they are moderately a good predictor of impairment when using marijuana, but there's nothing conclusive out there.

Najah: Okay. And I think this time, those are all the questions. Thank you, everyone, for attending, most especially Dr. Patel, for putting this presentation, very informative presentation together for us. Again, if you have more questions, or by some chance, there was a question that I did not see, feel free to reach out to myself or Dr. Patel. In the follow-up email I'm going to send out on Tuesday, only because I'm celebrating my birthday this weekend. So I won't be in the office tomorrow or Monday. I will send out the follow-up to this webinar on Tuesday. I will include the link to Dr. Patel's book. And again, if you have any questions, you can reply back to that email or you can just reply to Dr. Patel, where I'm gonna put her information in the email. When this is over, please, please fill out the survey. That will pop up on your screen, If by chance it does not pop up, feel free to email me and I will send over a survey to you. This concludes our programming for today, and thank you all for attending.


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