Alcohol Tests: Urine, ETG, Hair Follicle Screens
This is a quick primer on drug and alcohol testing. Because this site is on alcoholism it is highly tailored towards alcohol with a few tidbits on drug testing detection times.
I hope it is helpful.
Alcohol urine tests (for ETOH), otherwise known as screenings, are a scientific breakdown of a urine sample to determine if the individual in question has alcohol in their system. Such a test also reveals approximately how long it has been since the person last ingested alcohol. There are numerous reasons why an individual might need to submit to alcohol testing, many of which are related to employment, i.e. a person is believed to have consumed alcohol on work time, they need to be screened, or a person who has a legal obligation to a drug and alcohol test to make certain they are keeping alcohol free as part of their probation or parole.
The typical alcohol urine test will discover alcohol in your urine for about 24 hours after alcohol has been ingested. The individual who is being tested or screened needs to place a urine sample into a compact, sterilized bottle. Following the test, the bottle will have a chemical testing strip inserted into it, and the strip will react if there is any alcohol in the urine sample. The test should be sent to a laboratory, to verify the result. (Although, frequently drug and alcohol tests are only sent to a laboratory if the initial urine sample indicates a positive result for drugs or alcohol. This is to confirm the initial drug and alcohol test result. No one should be accused of a “dirty UA” without confirmation of the contents of the urine from a laboratory)
There are many factors behind an alcohol urine test, whether it is the application method or the detection process itself. The length of time between consuming alcohol last and taking the test will make a significant contribution to the quality of the result, and is most likely the determining factor. It may take as much as 2 hours for alcohol (ETOH) to be detected in urine. Then again, once in the urine, it is quite difficult to forecast how much time it’s going to remain in one’s body. (A bottle of beer may be gone in less than an hour).
Common Alcohol Test Detection Times:
If the test is used as a drug screen, it must be done within a certain amount of time after the drug was taken, or while forms of the drug can still be detected in the body. Examples are below:
- Alcohol: 3 to 10 hours
- Amphetamines: 24 to 48 hours
- Barbiturates: up to 6 weeks
- Benzodiazepines: up to 6 weeks with high level use
- Cocaine: 2 to 4 days; up to 10 to 22 days with heavy use
- Codeine: 1 to 2 days
- Heroin: 1 to 2 days
- Hydromorphone: 1 to 2 days
- Methadone: 2 to 3 days
- Morphine: 1 to 2 days
- Phencyclidine (PCP): 1 to 8 days
- Propoxyphene: 6 to 48 hours
- Tetrahydrocannabinol (THC): 6 to 11 weeks with heavy use
Detection times from:
http://www.nlm.nih.gov/medlineplus/ency/article/003578.htm
Another table from Drugs.com on detection time. I imaging it would be updated with every new detection technique and time for detection.
http://www.drugs.com/article/drug-testing.html
(more at the bottom of post)
Concerns About False Positives

A concern for anyone undergoing drug and alcohol testing is the possibility of a false positive result. Initial screening drugs tests may infrequently result in false positive results, although confirmatory (GC-MS) testing greatly lessens the chances of a false positive – reducing the risk to close to zero.4
It is important that a person undergoing drug testing complete an accurate history of all prescription, OTC, and herbal drug use prior to the time of the sample collection. Certain substances, over-the-counter (OTC) or prescription drugs may result in false positives due to cross-reactivity with other substances, although many assays have been reformulated to avoid these possibilities. For example, poppy seeds and dextromethorphan have been reported to lead to a false positive result for opiates, and decongestants (ephedrine) have been implicated in causing false positives for amphetamines. The body metabolizes codeine to morphine and both substances may be found upon testing. On the other hand, if benzoylecgonine, the main metabolite of cocaine is detected, the subject cannot claim that the result is a false positive due to Novocaine administration, or any other “-caine” drug. Benzoylecgonine is only found in nature as a metabolite of cocaine, and there would no other valid reason for it to be present in a drug screen.4 As previously mentioned, confirmatory testing with GC-MS will identify individual drugs or metabolites in a sample, and almost eliminate the chance for a false positive result.
Other abnormalities in the urine screen may indicate that results may be a false negative or that there was deliberate adulteration of the sample. For example, a low creatinine lab value can indicate that a urine sample was tampered with – either the subject diluted their urine by consuming excessive water just prior to testing, or water was added to the urine sample. Creatinine levels are often used in conjunction with specific gravity to determine if samples have been diluted. To help avoid this problem, the testing lab may color the water in their toilet blue to prevent the sample being diluted with water from the toilet.
Subjects may also attempt to add certain enzymes to the urine sample to affect stability, but this often changes the pH, which is also tested. The argument of inhalation of “passive” smoke from being in a room with people smoking marijuana is not valid, as the cut-off concentrations for lab analysis are set well above that which might occur for passive inhalation. All of these variables, and others, are looked at in the lab analysis, keeping one step ahead of those that attempt to foil drug tests.
In some labs, patients who receive a positive result may have the option to pay for an independent retest of the urine sample that was originally submitted. A new urine sample is not allowed for the retest as the drug in question may have been excreted from the body by that time.
The above false positive information taken from:
http://www.drugs.com/article/drug-testing.html
A longer detection time for alcohol urine tests is available
There is also an etg alcohol test that is generally done simultaneously with the urine test, and this analysis finds Ethyl Glucoronide in the urine, which is left in your urine after the alcohol has metabolized out of the body itself. This permits examiners to see alcohol usage for about 5 days beyond the last time alcohol was ingested. Sadly, the expense of the equipment is prohibitively high so only a few situations require this, such as probation/parole.
Here is a pdf on Common Issues In A Drug Court
In case any reader has a legal problem. It is from the year 2000, so it is dated.
Hair Follicle Testing
What is hair drug screening?
A hair sample drug test is an examination that uses a small sample of hair to identify specific drugs used by the person being tested. A hair follicle test measures the drug molecules and their specific metabolites that are produced only after the drug has been processed by the human body. After the drug is processed, trace amounts of its metabolites are inserted into the hair follicle by the bloodstream.
What time period does a standard hair follicle test cover?
A standard hair follicle screening covers a period of approximately 90 days, but is susceptible to time variation depending on the growth rate of your hair. The hair sample is cut as close to the scalp as possible and the most recent 3.9cm (or 1.5 inches) are tested. It is possible to go back even further than 90 days since the time period is limited only by the length of the hair sample, but is standardized to a 90 day history.
What type of drugs can be detected in a hair follicle drug testing?
- Cocaine (Cocaine & Benzoylecgonine)
- Marijuana
- Opiates (Codeine,Morphine & 6-Monacteyl Morphine)
- Methamphetamine (Methamphetamine/Amphetamine & Ecstasy)
- Phencyclidine (PCP)
These five drug classes are mandated for testing by the Federal Government.
Above from:
http://www.ipassedmydrugtest.com/hair_drug_test_FAQ.asp
Click above for much more (low BS, high utility) information on the hair follicle test
Alcohol Testing Detection Times

So this was a primer my primer on drug and alcohol testing. For more specific information I am going to leave it up to the experts.