I will be getting a hair alcohol test soon. It could be either FAEE or ETG. At the time of the test, I will have been completely sober for 2 years, followed by a week of drinking about 6 drinks per day, followed by 2 weeks of complete sobriety. Will the hair test be able to detect that little amount of alcohol?

I guess I have to ask why 6 drinks a day for one week, then sober again after 2 years

Vacation to celebrate proposal following monitored sobriety. Then anticipating being reevaluated for potential further monitoring.

When was the last time you drank? Who is doing the testing?
Most Hair Alcohol (HAT) Tests check for both EtG and FAEE. Are you in US or UK?

In general, HAT is hit and miss. Has been used in US only since 2008. The jury is still out in relation to how the metabolites get into the hair. Low quantities of alcohol usually do not register, and even long term high dosage does not show up in many. No track record in US. Most of the promotion is through the Society of Hair Testing (SoHT) which is composed mostly of those interested in promoting economic interest.

At the time I get the test, I will have not had anything to drink for about 3 weeks. Prior to those 3 weeks, I plan on having a period of 3-5 days where each day I consume about 50-60g ETOH per day. Those 3-5 days will be my first days drinking in over 2 years. This is taking place in the US but not for a court system.

As you are probably aware, these tests have a cut-off, leastwise should. HAT has been used in the UK for some time and usually restricted to determining excessive alcohol consumption... classed as above 30g daily intake. But the instruments used have a much lower level of detection (LOD). So in determining if X amount will show up on a test the only history that can be called upon is for a fixed cutoff which doesn't tell us anything about lower quantities.

Your drinking pattern is interesting. The quantities are just below the average consumption detected in PEth, clear of EtG window, and probably escape blood testing MCV, GGT etc. You must have put a lot of thought into this stealth drinking system.

HAT is known to be erratic in detecting any but excessive consumption and even then it's spotty. But that doesn't mean it won't pickup lesser usage. It's simply unpredictable.

Here is a study that involved a number of female drinkers, but at lower quantities than you propose.

Ethyl glucuronide in human hair after daily consum... [Forensic Sci Int. 2011] - PubMed result

You will note it detected only 5 out of 21, all at levels below cutoff and also showed positive for 2 in the abstinent control group. Not impressive results.

I think your proposal depends on the cutoff, individual metabolism and luck.

Thanks for the help, Bill! I agree with your assessment based on my own research. One question I have regarding the study you linked: does hair testing reveal EtG concentrations per time, or is it merely an average over the 3 month detection period? In other words, if all of the subjects consuming 1 drink daily for 3 months passed the EtG test, how is that different from consuming 90 drinks in 1 day?

If my hair test window of 90 days includes 85 of complete sobriety, 3 of having 1-2 drinks per day, and 2 of having 4-5 drinks per day, am I correct in saying that I likely will not test positive, and if I do, it will be at low enough level that I can strongly argue that it's inaccurate?

Interesting discussion but I have to ask, why do you ask? You are allowing yourself to be tested and the results will be whatever they will be. Nothing you can do about it now so why bother worrying or asking. Since this is a test outside of the courts I'm going to assume its for a job requiring sobriety or for security clearance, am I close?

"Thanks for the help, Bill! I agree with your assessment based on my own research. One question I have regarding the study you linked: does hair testing reveal EtG concentrations per time period, or is it merely an average over the 3 month detection period? In other words, if all of the subjects consuming 1 drink daily for 3 months passed the EtG test, how is that different from consuming 90 drinks in 1 day?"

HAT is different from other drug testing in that FAEE and EtG are created by different pathways and act differently in the hair. Both are inclined to migrate up the hair shaft but FAEE more so. Any drug that doesn't stay put on incorporation cannot be time estimated. The claim that hair testing can tell when a substance was used is a dubious claim at best. It's called segmental analysis and amounts to aligning the root ends of the hair sample, cutting it into 1-cm segments that can be analyzed individually. This assumes an average hair growth rate of 1.3 cm per month and also that the drug enters via the hair papilla at the base of the follicle. Neither proposition is true. Hair growth varies from .5 to 1.5 cm between individuals and how a drug gets into the hair varies by class.

It is generally believed that FAEE is deposited in hair from the sebaceous glands and it is probably synthesized there as well. Susanna Vogliardi in her doctoral thesis (2008) provides an excellent illustration of the various avenues through which drugs are incorporated into human hair (see Figure 2). Available here.

When testing for alcohol the focus is on the first 1-cm of the sample. That part closest to the scalp. The reason for that is that the metabolites move up the shaft, rather than staying in place, and they are unstable in hair and likely to be removed by normal hair washing, exposure to sunlight, etc. (That is the recommendation, but testing labs seldom follow recommendations)

So they will pulverize about 1-1/2 in of your hair and test it. There is no way to do segmental analysis as there are no segmental cutoffs for the reasons noted above. They are simply looking for cumulative EtG and a combination of 4-FAEEs.

All of the literature is clear in that moderate consumption does not usually create EtG and/or FAEE at detectable levels. However, moderate is defined as 2 drinks per day for a female. There are no studies on 60g per day across 5 days and I have no means of calculation. It might come down to the rate of consumption. Drinking slow across a longer period (1 drink every 1-1/2 hours) doesn't result in BAC buildup.

Just read this month's USDTL* Newsletter. Contains a section of EtG hair test that states "for females, EtG in hair gives a very inaccurate picture of their alcohol consumption history." They attribute this to "female students using various types of chemical treatments on their hair..."

This is consistent with past research on degradation of drugs in hair through normal hygiene. This is one of the first to highlight the male/female variance.

See USDTL Newsletter

*United States Drug Testing Laboratory