"We were wondering about the use of alcohol based hand sanitizer which we use countless times per day and the effect on EtG.  We tried to research it on the Internet, and it says that it is absorbed by the body, however it stated that studies on those in recovery have not been performed.  Could you please let me know your thoughts on this?  Thank you for your time."

Looking at superimposed graphs of blood alcohol levels from one drink in a men and one drink in a women, the women will have a higher blood alcohol level.  Is this true also with the ETG levels?  Theoretically, a women would have higher blood alcohol levels with incidental use also, and therefore higher ETG results. If this is true, shouldn't the cut-off levels be different for male and female?

We've had a few instances of positive urine alcohol (low levels) and negative ETG. We are suspecting perhaps our lab cut off for urine is lower and more specific, than the cut off for ETG. What do you think?

Does warm weather during shipment cause a more rapid breakdown of EtG in urine?

Questions concerning the AWOL vaporizer:

What about incidental alcohol use, such as in food, mouthwash, communion wine, etc?

Should an EtG always be performed to confirm a positive urine alcohol test?

Why are cutoff values different from different labs?

Are there any meds that would give a positive EtG?

What about polyethylene glycol? Can it cause a positive EtG?

"We were wondering about the use of alcohol based hand sanitizer which we use countless times per day and the effect on EtG.  We tried to research it on the Internet, and it says that it is absorbed by the body, however it stated that studies on those in recovery have not been performed.  Could you please let me know your thoughts on this?  Thank you for your time."

    Yes, We were concerned to evaluate Purrell Gel that has a high content of ethanol (>70%) and is commonly used in hospitals and elsewhere. To tentatively evaluate this we have had individuals used large amounts of the product and to date have had none show up with a positive EtG in urine. We have not evaluated this with pathologic skin conditions, however, we doubt if enough is absorbed through the skin to yield a positive EtG test.

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Looking at superimposed graphs of blood alcohol levels from one drink in a men and one drink in a women, the women will have a higher blood alcohol level.  Is this true also with the ETG levels?  Theoretically, a women would have higher blood alcohol levels with incidental use also, and therefore higher ETG results. If this is true, shouldn't the cut-off levels be different for male and female?

    Probably not, however, this has not been specifically examined. There appears to be much variation in how much EtG one individual produces compared to another (due to polymorphism of the enzyme systems), which is probably a more significant factor than between men and women. Also, because less than 0.1% of alcohol is metabolized into EtG, and because of urine concentration/dilution factors, time frame, etc, It is doubtful that it will be possible to have exacting precise cutoffs. In other words, the cutoff levels will need to be fairly high anyway and will probably not be greatly affected by slight changes in serum alcohol levels. However, time will tell, as more research is performed.

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We've had a few instances of positive urine alcohol (low levels) and negative ETG. We are suspecting perhaps our lab cut off for urine is lower and more specific, than the cut off for ETG. What do you think?

    Urine EtG is actually more "specific" than urine alcohol since you can have alcohol in urine without drinking (if it ferments there) but the only way you can have EtG in the urine is if alcohol is in your body. So there are really only three reasons you can have a positive urine alcohol and negative urine EtG. 1. The alcohol fermented "in-vitro" in the urine, 2. The urine was obtained within one hour after drinking, since it takes EtG a little longer to appear in urine than alcohol, or 3. The cutoff value for EtG is too high.

   In the case of #1 there is evidence that not only can yeast ferment alcohol but also some bacteria and the amount of glucose necessary can be small. So it's not just in diabetics with yeast in the urine that fermentation occurs. In the case of #2 it doesn't make much sense that someone would drink and then give a urine sample within 1 hour. In case #3 some labs are setting the cutoff for EtG high to avoid positive EtGs from "incidental alcohol use" and this is making EtG less sensitive.

     In conclusion, we are using a 100 ng/ml cutoff and if the urine is positive for alcohol but negative for EtG we are assuming it was probably in-vitro fermentation (ie a false positive test). Nevertheless we still confront the participant and ask them if they've been drinking but we drop it there if they say no. We've not yet had one of this type who've admitted drinking.

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Does warm weather during shipment cause a more rapid breakdown of EtG in urine?

    Recent experiments show that heating urine to 100 C (boiling point of H2O) actually increased the stability of EtG. The data are showing that at room temperature, in some individuals with nitrites and/or blood in urine, that EtG can deteriorate over a week. We are surmising that  esterases associated with infection may be causing breakdown of EtG. Heating seems to prevent breakdown, possibly due to neutralizing the bacteria. So, the fact is that heat doesn't cause breakdown of EtG, it actually increases stability.

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Questions concerning the AWOL vaporizer:

    We have recently become aware of a “new” method of alcohol abuse known as Alcohol Without Liquid (AWOL) vaporizer.

One of the web sites:  www.awolmachine.com

    We were concerned that AWOL would invalidate EtG urine testing and asked a forensic lab for an opinion.  Following is the response from Dr. Ed Barbieri from National Medical Services, Willow Grove PA:

 ”We have looked into the AWOL machine from the website.  Alcohol may enter the bloodstream in the manner that is described on the web site. For ethanol to get to the brain it MUST enter the bloodstream.  If ethanol enters the bloodstream, it will be distributed to other tissues throughout the body including the liver and, therefore, will be metabolized.  Once metabolized, ethylglucuronide can be formed and will be eliminated (along with some ethanol) into the urine.  In summary, if someone is choosing to take in ethanol in this manner, it will still be metabolized through traditional pathways that may result in positive EtG findings.  The EtG results would be dependent upon the time from exposure, amount etc., all of the same things that would need to be considered if alcohol was ingested in a liquid form through drinking."

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What about incidental alcohol use, such as in food, mouthwash, communion wine, etc?

    This is an important question and an important issue to understand. Ethanol, unlike other drugs, is fairly ubiquitous in our environment. It's in food (ie vanilla extract). It's used as solvent in "over-the-counter" meds. It's used in ceremonies (i.e. communion, etc). It is recommended that anyone being tested (i.e. those in monitoring following alcohol problems) be advised that they should not consume food containing alcohol, avoid OTC meds containing alcohol, mouthwash with alcohol, and/or communion wine or anything else containing alcohol. It is possible in some circumstances that the urine EtG level could exceed the cutoff levels by this type of "non-beverage alcohol" exposure. However, it is very unlikely that an EtG level >500 ug/L could be obtained through incidental, non-beverage, alcohol intake. Therefore, between the cutoff level of 100 ug/L and 500 ug/L it is possible that the alcohol consumption was incidental. An EtG level greater than 500 ug/L is highly likely to be due to beverage alcohol consumption. One way to think of this is that EtG testing is similar to opioid testing where dietary use of poppy seeds can lead to a true positive morphine level but only up to about 2000 ng/ml beyond which it is very unlikely to be due to poppy seeds. Likewise it's important to encourage individuals in monitoring to avoid poppy seeds.

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EtG appears to be highly specific, similar to testing for other drugs. It is a direct metabolite and is only present in urine following alcohol consumption. However, no forensic toxicology test is 100% reliable. Therefore, we strongly recommend that for all urine tests found to be positive that the individual be referred for in-depth clinical evaluation. It is important with any laboratory test to obtain clinical correlation!

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Should an EtG always be performed to confirm a positive urine alcohol test?

Here's our thinking on the issue: Urine alcohol can have false positives primarily due to in vitro fermentation. It's a good idea whenever there's a positive urine alcohol to do a urine glucose and look for yeast. In some labs this is routine. The problem is that if there is glucose and yeast it still doesn't mean that the individual did not drink alcohol, it just makes it more likely that it could have been a false positive. In addition to false positives from fermentation, there's also been a question of positive urine alcohol tests due to non-beverage alcohol consumed (mouthwash, food, otc meds, etc) at just the right time prior to urine testing. (not really false positive but not representing alcohol consumption).

Okay, now we have EtG testing. What a great test. At the thresholds we are have established it has a very smaller chance of being a false positive. Less than 1% of alcohol is metabolized via the EtG pathway. You therefore have to drink significantly more for it to show up. Also, in vitro fermentation does not cause a positive EtG, which is only formed in the liver.. Smaller amounts of alcohol consumed in mouthwash or food, etc, would also not produce enough EtG to get over the threshold as readily. The flip side for EtG is that there is a chance, with small amounts of alcohol consumption, of having a false negative (just like urine alcohol, which can frequently be negative after drinking). The EtG needs a significant amount of alcohol consumed to be positive.

   So here's what to do. For a positive urine alcohol, confront the individual regarding the positive test. See what they say. If they admit to drinking alcohol, of course you don't need to test further. If they deny use then you have a couple options: 1. You can advise them that there's a new test that can help corroborate their contention that they did not drink. They would be wise to let you run the test (on the same urine specimen) to clarify the positive urine. Everyone I've done this with thusfar has readily agreed. If they refuse inform them that it will certainly appear that they are avoiding clarifying the issue and appear more likely that the urine alcohol is a true positive. and/or 2. You can run the EtG anyway (since you certainly have the agreement for forensic testing). You can charge them or pay from your program (depending on how you want to do it). If they complain you can tell them you did it for their benefit because of a positive urine test. I've done it both ways. Usually the last thing they are worried about when this comes up is $65 dollars.

   Okay, if the EtG is negative I would consider the urine alcohol a false positive and drop it. (This doesn't actually prove it is a false positive, however, it substantially increases the likelihood.) It's my opinion that it is far better to miss a true positive (because you can catch them later, and you surely will). The worst thing would be a false positives which wrongly incriminates them and it destroys trust and wrongly diagnoses them and, of course, the consequences can be harsh.

   If the EtG is positive, let them know you now have absolute proof they consumed alcohol (a positive urine alcohol and a positive EtG). Do not waver from your confidence and the chances are, in my experience, if you provide hope fot them despite their relapse that 90+% will confess and accept help. The manner of approaching them in this situation matters. I just say, "we now know you did drink alcohol and it's not the end of the world, we just want to get you some help.". The more legalistic the process has been prior to this point, with that individual, the higher the likelihood they will "lawyer up" and fight it. What a sad situation that is!

   If it goes to court and your program has to defend the test we will help you. There is enough data now that we believe we can defend it in court. Especially if there is a positive urine alcohol and a positive EtG. This is pretty much a no brainer!

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    CLIA, is an acronym for Clinical Laboratory Improvement Amendment. This act is about defining "certification" for labs and not lab tests. Some tests, minor office tests like urine dipstick, etc, are exempt, such that any medical office can do them without CLIA certification. EtG testing is not exempt, in this sense, however, it would not be a consideration, I'm sure, to run an EtG in a non-CLIA lab (ie an office test).

    What they are probably asking about, and asking it wrong, is about whether or not EtG is FDA approved as a diagnostic test. The answer is no. Currently it is being performed as a toxicology test which does not require approval.

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Why are cutoff values different from different labs?

    Re cutoffs values: What determines the best cutoff level is complicated. It is a balancing act.  The cutoff values should not be so low that the test picks up extraneous alcohol intake (food, mouthwash, etc) resulting in "false positives." On the other hand it is not desirable for the threshold to be too high, which reduces sensitivity, and would create more false negatives. Another important issue is purity of the testing method. Depending on the technique and its accuracy the cutoff level can be important to reduce intrinsic variations that cause errors from the test. NWT believes they have developed a superior method and can substantiate the quality of its selection of cutoff at 100 ug/L.

    Also, we know that very little alcohol (.02-.06%) is metabolized by non-oxidative glucuronidation. The "standard drink" in the USA is 14gm (about 1.5oz of vodka, 12oz beer, 5oz wine). Thus the small fraction of alcohol actually metabolized this route means that a significant amount of alcohol would have to be consumed to register positive even with a cutoff of 100 ug/L.

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    EtG is formed in the liver of someone when ethanol combines with activated glucuronide. This is the only way it is formed. When EtG is detected in the body (usually urine, however, it can be detected in other body fluids and in hair, etc) it means that ethanol is in the body. Incidental alcohol exposure, from food, mouthwash, otc meds, communion wine, or even skin exposure to alcohol, usually causes a very mild elevation of EtG in the urine (<100 but almost always <500). Therefore for urine EtG >500 ng/ml you can usually be almost certain beverage alcohol has been consumed.

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Are there any meds that would give a positive EtG?

    There have actually been no false-positive tests for EtG to date. Only ethyl alcohol seems to produce EtG. The issue is really more where did the alcohol come from? Many medications include ethanol as a solvent (cough syrup, etc) and therefore could cause very low level of EtG (usually < 100 ng/ml), however, no medication causes elevated EtG, that we know of, it's just the ethanol being used as a solvent with the liquid medications.

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What about polyethylene glycol? Can it cause a positive EtG?

    Probably impossible! Polyethylene glycol can be found as an ingredient in various tablets and OTC meds. There is no evidence that degradation of this compound produces ethanol, especially in enough quantity to cause a positive EtG test.

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The answer is I hope not but it could happen.

    In my experience cutoffs can be for at least two purposes, 1. To be sure the drug is actually present (ie high enough over Level of Detection, that background noise, variability of controls, etc, are satisfied), and 2. To eliminate incidental environmental exposure (for example, setting marijuana level high enough such that second hand smoke exposure can't be claimed as an excuse for a positive.)

    Specificity and sensitivity always compete. Setting the cutoff high sacrifices sensitivity for specificity and two low the opposite.

    A good example of this is to consider what's happened with morphine/codeine cutoffs historically. For years, the cutoff was 300 and it was known that positives could be from poppy seeds. Studies, however, showed that poppy seeds could rarely cause a level over 2,000 and never over 5,000. This was valuable info for MROs, so that we could stratify our level of concern based upon this info and the patients reaction. For example, if a morphine level came back at 400 we would call the patient and let them know they'd tested positive for morphine and ask if they've been taking morphine or codeine. Some patients would admit diversion explicitly or implicitly by making up an untenable excuse. Others would act surprised and say there's no way it could be valid. Sometimes further inquiry revealed they were exposed to poppy seeds. If they denied using when the level was less than 2000 we would usually report the test negative.

    This seemed to be a reasonable approach, until inexperienced or overly reactive individuals received reports and didn't bother to involve an MRO or whatever the reason, there were tenacious false-accussations, with borderline levels, that resulted in much trouble, unhappiness, etc.. One way to avoid this would be to better train people or involve qualified MROs, however, the powers that be decided to raise the morphine cutoff to 2,000. This results in fewer "false positives" and less work, however, it sacrifices earlier detection.

    The same thing may happen with EtG cutoffs, which would be a shame, since the primary value of EtG testing is the longer timeframe of detection which would be reduced with increasing cutoff.

    In my opinion the ideal situation is to have a cutoff that assures ethanol was consumed (i.e. 100) and a second cutoff that is very unlikely result from casual incidental contact (500-750). (A problem with this, that we are discovering, is that "casual incidental exposure" can be a very large amount of ethanol. In one case a doctor admitted he was adding an entire bottle of vanilla to his coffee each morning. This turned out to be 2 standard drinks. Would this be incidental exposure?) His level was 820. In another case, communion wine was blamed, which allegedly was consumed almost daily.

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    Yes, the difference is 1,000. Some of the confusion stems from the fact that the European literature uses lower figures. For example in the European literature .4 mg/L or = .4 ug/ml and in the USA the same amount would be expressed as 400 ng/ml or 400 ug/L. We've just got to make it confusing don't we.

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