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OPAM Workshop: Medical Review Officer Training Cou ...
285274 - Video 16
285274 - Video 16
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Video Transcription
I'm Barry Sample, and I would like to talk to you now about alcohol testing. First, I'd like to start with the disclosure. Currently, I'm self-employed. I retired recently after 40-plus years in the drug testing industry, and I'm now working as a consultant with a variety of laboratories and IED companies. So as we talk about alcohol testing today, we're going to touch on the scientific and technical issues, provide some background, talk about some of the physiology, as well as practical issues in actually performing the tests and potentially legal issues. So the effects of alcohol are well-known, intoxication, alcoholism, potentially fetal alcohol syndrome, association with breast cancer, liver disease. Intoxication can occur at very, very low levels, not just the 0.08 that you think about for driving under the influence. Impairment can actually occur at levels as low as 0.01%, which gets complicated if individuals are also taking other drugs, polypharmacy, you can have multiple impairment effects. And one of the things about alcohol is that relative to other drugs, the body tolerates a relatively high dose. So this table shows different blood alcohol concentrations and the degree to which an individual would be impacted. So at levels of 0.02% may observe decreased restraint, decrease in awareness, 0.04, negative impacts on comprehension and concentration, which is why that level is so important for driving, impaired judgment at 0.06, where you could have a three-fold higher risk of an accident, 0.08, which is the national DUI limit, where 100% of the drivers are considered to be too intoxicated to drive, has a five-fold greater risk of accident. But there's also muscle, loss of muscle control, sensation associated with that level, 0.1, the level of 0.1% is associated with a seven-fold increase in accident risk. At twice that, at 0.2%, where people may start losing equilibrium and being sleepy, a 30-fold greater risk of accident, and at increasing levels, higher and higher capacity and loss. So death is oftentimes associated with levels of 0.5% and higher, although I've seen people walking, talking, fully functional, even at levels that exceed 0.5%. So let's go back to college for a second and visit our old friends, ADME, absorption, distribution, metabolism, and excretion. So looking at, first of all, alcohol absorption, alcohol is typically completely absorbed within 30 to 60 minutes, however, the presence of food in the stomach can slow that absorption. The amount of gastric alcohol dehydrogenase that's present will impact the amount of alcohol that's ultimately absorbed into the bloodstream and would have effects on the body. So women generally have 50% less gastric alcohol dehydrogenase than men, and male alcoholics also have less. So if you have less alcohol dehydrogenase, more alcohol will be absorbed, and the greater potential impact from a given dose of, or a given dose or a given drink of alcohol. In terms of distribution, alcohol distributes in body water, men about, equates to about 60% of their weight, women about 50%, does not bind to plasma proteins, and solubility in fat and bone is negligible. We look at the relative distribution in various body compartments, with blood representing a level of one, urine, the ratio of urine to blood is 1.3, although, and we'll touch on this in a little bit, that's not all the time, only occurs under certain conditions. Saliva 1.12, breast milk 1.1, brain much less so fat, we said it's not lipophilic, 0.02, and the ratio of blood to breath is set at 1 to 2100. Alcohol is well metabolized, 99% ultimately is metabolized generally, or 95 to 99%. It is metabolized through, first of all, alcohol dehydrogenase, which can either be gastric or hepatic in nature. The resulting metabolite then undergoes further metabolism by aldehyde dehydrogenase, and one of the things about alcohol is that it very quickly, after one drink, exhibits zero order kinetics. The rate of elimination is constant, it's not proportional to the amount that's on board. This shows it graphically, so about 5% of ethanol is excreted unchanged, or up to 5% is excreted unchanged in the sweat, urine, and breath. Roughly 95% is metabolized to acetaldehyde, and then ultimately to acetic acid, but those individuals that have decreased aldehyde dehydrogenase are the ones that have the characteristic flushing due to the buildup of acetaldehyde, and a very, very small amount, very minor metabolites are excreted as either ethyl glucuronide or ethyl sulfate, but we'll touch on that at the very end. Smoking increases the metabolism. Smokers generally have about a 40% increased metabolism. Chronic alcoholics have increased metabolism, maybe increased as high as 0.035 grams per deciliter per hour in binge drinkers, as compared to the more normal, at least in males, 0.015 grams per deciliter per hour, and the use of oral contraceptives can decrease metabolism. So you can see for women, especially women that are taking oral contraceptives, they are likely to have higher blood concentrations given a given dose of alcohol due to decreased metabolism as compared with men. So again, this touches on the elimination that we just talked about. And this shows data from alcohol elimination rates in drinking drivers, and you can see the range of values here, milligrams per milliliter per hour. So let's talk a little bit about alcohol concentration units, because the number of units you used and that can sometimes lead to some confusion. So one milligram per milliliter would equal 100 milligrams per deciliter. 100 milligrams per deciliter is 100 mils, so 100 milligrams per 100 mils would be the same as 1 milligram per 1 ml. 100 milligrams is a tenth of a gram, so that equals 0.10 grams per deciliter, which equates to 0.10%. So different units, but they all represent the same concentration. While the ratio of blood to breath is set at 1 milliliter of blood would be equivalent to 2,100 milliliters of air, so consequently 0.1% blood alcohol would be equivalent to 1 milligram of alcohol per 2,100 milliliters of air. But as you can see on this slide, the actual ratio may vary somewhat between individuals. So this is a study looking at 793 individuals and measuring the blood-breath ratio. There is somewhat of a distribution, but administratively and by consensus, that ratio has been set at a ratio of 1 to 2,100. This shows data graphically comparing blood ethanol and breath ethanol results. And it fits very nicely with the 2,100 ratio of 1 milligram per 2,100 milliliters. In urine, as we touched on, you have 1.3 times the concentration, however, that occurs after the peak and after about two hours of drinking. In addition, the correlation is much better with the second void. So in other words, in order for that ratio to hold true, one would need to empty the bladder and then collect a specimen within half an hour or so of the previous void. And then you'll see that ratio of 1.3 to 1. Typically, urine alcohols, unless it's done in this type of manner, are not very useful in trying to assess whether or not somebody is impaired or what the blood concentration would be. In addition, urine testing is further complicated by in vitro or even in situ fermentation or neo-formation. So if an individual has glucose as well as yeast in their urine, so if they're spilling glucose and the specimen is bacterially contaminated with yeast, it can also form ethanol, which is why many laboratories, when they test for urine alcohol, may also report either qualitatively or quantitatively the glucose level in the urine specimen in order to help assist in the interpretation of a positive urine alcohol test. In this slide, you can see the correlation between the urine alcohol and blood alcohol. Saliva, similar type of data showing the saliva ethanol to blood ethanol relationship across a range of concentrations. And interestingly, the slope is very, very close to what we described earlier at 1.09. I should have mentioned on this previous slide in the urine to blood, you can see the slope of 1.28 correlates nicely with the ratio between urine and blood alcohol as well. This slide shows the time course in blood, breath, and saliva. time zero up until 420 minutes, or six hours after, sorry, seven hours after beginning of drinking. And you can see the decline in blood alcohol and corresponding breath and saliva decreases as well, which are very well correlated between those three specimen types. So as we look at the history of alcohol testing, dichromate testing for alcohol started as early as the mid 1860s, early 20s. Concerns about drunk driving arose and started being used medically in the 20s as well. More information continued to emerge regarding use of alcohol and its adverse effects. The first appellate court decision on alcohol test dates to 1937. And in 1938, both the American Medical Association and the National Safety Council recommended a DUI level of 0.15%. And if you think back to our earlier slide relative to impairment, that's quite a high level and is significantly higher than today's standard of 0.08%. The first breath testing device dates to 1941. And in 1965, the National Safety Council recommended lowering the breath alcohol or blood alcohol cutoff for DUI to 0.10%. One of the early and important legal cases was a Supreme Court ruling in Schmerber pertaining to, partly pertaining to random alcohol testing and the fact that there's no Fifth Amendment protection that it's not, breath alcohol test is, or blood alcohol test is not self-incriminating. DOT issued national standards in 1969, National Highway Traffic Safety Administration established standards for drunk driving in 73. And then in 1989, Supreme Court upheld alcohol testing in Skinner, the Federal Railroad Administration case regarding the random testing for drugs and alcohol. 1991, the Omnibus Transportation Employee Testing Act or OTETA set a number of standards related to drug and alcohol testing. And it was in 1994 that the DOT issued its alcohol testing regulation and the various modes also did. And nationally, a DUI level was set in 1998 of 0.08%. And, you know, it really wasn't done exactly by national mandate, but states were incentivized with about $500 million in order to encourage them to institute this national standard of 0.08%. So what are some of the relative advantages and disadvantages? You know, breath has the advantage that it's a point of collection test, essentially. You have immediate results. It is, you know, the first in a two-tier testing process. But some of the disadvantages is that it has a high startup costs. There's a lot of training, you need to be concerned and ensure that the individual isn't tampering with their breath and negatively impacting the quality of that result. Blood has laboratory accuracy. It has the ability to have a retained specimen. You can do split testing, you can do retesting, but it's invasive. It may require a licensed technician to collect or even test the specimen if you're talking about DUI laboratories. And there's a delay in getting the result. You don't have that immediate result. In the case of urine, well-established collection process, you have the ability to retest because you have a retained specimen. But you can't do it on one specimen. We talked about an individual to utilize urine to really assess whether or not somebody may or may not be impaired. They would need to void and then a second specimen be collected. And the correlation, although it looks relatively good, the correlation is still less well-established than breath. Saliva provides an immediate test result. It's portable, it's cheaper than breath alcohol testing, correlates well with blood, but it's only a preliminary test. It does absolutely require some type of confirmatory testing. And if you look at where alcohol testing may occur, if it's on-site, you have that immediate result. If it's saliva or breath. Any specimen type that involves laboratory testing, there'll be delayed turnaround time. The accuracy of on-site testing is variable depending upon whether it's a screening test or an evidential test that's performed. And we'll get to that in just a second. May not have the same degree of chain of custody for on-site test as compared with laboratory testing, but on-site testing is generally less expensive, although somewhat dependent upon the technology that's used as well as the volume of tests that that site performs. And general laboratory testing would be more expensive. So what type of methods are used for on-site testing? So in breath. There are screening devices, which can be fuel cells, a chromate type test, a chemical test, or evidentiary devices, which can be infrared tests and or few cell technology. For urine screening, it could either be enzymatic or chemical depending upon the specific device that's being used. Saliva screening devices are enzymatic, they're not chemical, doesn't use dichromate. But again, it's only a screening device. And while sweat in theory might be possible, there are no tests that are currently marketed for that. So what are some of the issues? So from a legal perspective, Schmerber established in 1966 that blood, breath and urine are not self-incriminating, therefore there's no Fifth Amendment protection. The evidentiary versus screening devices. So only those evidentiary devices that appear on the NHTSA conforming products list can be used for confirmatory testing. They can also be used for screening, but any onsite confirmation must use an evidentiary device. There's no preservation of specimens with a breath testing device. So under DOT rules, breath alcohol is perfectly acceptable and is a recognized standard for determining whether or not somebody is impaired or able to drive. However, in certain states such as Minnesota that regulates point of collection tests, there's a requirement in Minnesota that there be an ability to have a retest of a specimen. Obviously if in a breath, there is no preservation of sample. It's not possible for the individual being tested to demand or have another portion of their original specimen retested. So as a consequence for non-regulated testing, I'm not talking about DOT here, but for non-regulated testing, you can't use breath alcohol testing in the state of Minnesota. And then the drunk driving standard versus the workplace workforce standard. So while 0.08 is now the national standard, in the past it's ranged from 0.08 to 0.1%, but the standard under DOT and workforce testing rules is 0.04%. With respect to ADA, a test for alcohol is a medical test, although that may not apply to breath. You cannot do alcohol testing pre-employment. It cannot be one of those tests, like a drug test that's done as a conditional offer of employment. Current alcohol use is not protected. So if somebody is currently using it at the workplace, if they're under the influence of the job, if it's a violation of federal and state regulations, then ADA doesn't come into play and adverse actions can be taken in the event of a positive test for alcohol. Under CLIA 88, the Clinical Laboratory Improvements Acts that regulates laboratories, breath alcohol tests are not covered. So long as those tests are not being done, sorry, breath alcohol tests are not being covered, but alcohol tests and blood, urine, and saliva would be covered if it's being used for medical purposes, but not if they're being done for employment purposes, which are exempt from CLIA. And as I mentioned earlier, as we were talking about Minnesota, some individual states may regulate point of collection, alcohol, and drug tests. So what's the role of the MRO? Well, there really isn't one. MRO is not included in the DOT alcohol regulations. Why? Because a .04 is a .04. If you're a .04, that's a violation of the rules. There's no alternative medical explanation as you might have with drugs and prescription use of drugs. However, the MRO can serve as or supervise a substance abuse professional. They can play a role for any alcohol testing that's not being conducted under federal regulations. They can help employers in development of testing programs, and they can also provide advice on alternative tests. So what about the biomarkers, ETG, ethyl glucuronide, and ethyl sulfate, ETS, and also phosphatidyl ethanol, or PEF? Those are not allowed under HHS, DOT, or NRC rules. ETG and ETS, and PEF for that matter, only show previous ingestion. They do not correlate with impairment. MRO review is certainly required. And specifically when we're talking about ETG and ETS, some major issues and concerns revolve around what cutoff may be utilized. As we've discussed previously, the lower the cutoff, the longer the detection window. However, because of the concerns surrounding incidental exposure, whether it be from food products that contain a small amount of ethanol or cough syrups, or more critically, particularly for healthcare workers in today's COVID age, the heavy use of hand sanitizer, the lower the cutoff, the more risk one may have for incidental exposure resulting in that positive. So there is a place for ETG and ETS in workforce testing, but probably not something that should be done on a routine basis, particularly in light of the fact that ethanol remains a legal drug and the point in workforce testing is to ensure that they're not impaired in the workforce. Thank you very much.
Video Summary
Barry Sample, a consultant with over 40 years of experience in the drug testing industry, discusses alcohol testing, touching on scientific, technical, practical, and legal aspects. Alcohol's effects, such as intoxication and potential health risks like fetal alcohol syndrome and liver disease, are well-known. He highlights that impairment can begin at low blood alcohol levels, complicating matters when combined with other drugs. The talk delves into the body's absorption, distribution, metabolism, and excretion of alcohol, noting differences between individuals such as men and women due to variations in gastric alcohol dehydrogenase. Various methods of alcohol testing, including breath, blood, urine, and saliva, are compared, each with its own advantages and disadvantages. Legal cases and standards, such as the Supreme Court's decisions and the DOT's regulations, are also discussed. Finally, he explores the roles of medical review officers and the use of biomarkers like ETG and ETS in workforce testing.
Keywords
alcohol testing
fetal alcohol syndrome
blood alcohol levels
gastric alcohol dehydrogenase
biomarkers ETG ETS
legal standards
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