Alcohol Test: Breath, Blood, Urine, Hair, Breast Milk, Saliva

According to the “Global status report on alcohol and health” by WHO, alcohol addiction is a worldwide problem. It causes hundreds of thousands of deaths every year. It is a precursor to violence, injury, and several diseases.

Furthermore, the negative impacts of alcohol spread throughout a family, community, country, and beyond.

Alcohol consumption by the general public is increasing rapidly. Consequently, there is a growing demand for more alcohol testing, screening, and detection.

Testing for alcohol through clinically proven methods verifies the use of alcohol over a period of time by an individual.

When do you need an alcohol test?

One may have to undergo an alcohol test for a variety of reasons, such as:

  • Pre-employment screening
  • During the probation period for alcohol-related crimes
  • Mandatory workplace screening programs for alcohol use
  • For granting visitation permit or custody of children
  • Identifying drivers suspected of drinking and driving
  • For de-addiction treatment and rehabilitation
  • As a part of the police investigation procedure in criminal cases

Levels of Alcohol Consumption

Ethanol, or ethyl alcohol, is the only type of alcohol suitable for consumption without harming yourself. The percentage of alcohol in the system is the amount of ethanol consumed.

  • Abstinence: No consumption of alcohol
  • Occasional Drinking: If you consume less than 40 grams of pure ethanol a day then it is within the occasional drinking category.
  • Alcohol Abuse: Excessive use of alcohol is defined as consuming more than 40 grams of pure ethanol a day. Half a bottle of wine has over 40 grams of ethanol.

Types of Testing

We are all familiar with police officers testing drivers with breathalyzers for alcohol.

For assessing current intoxication or a history of prior alcohol and drug consumption, a variety of specimens and methods can be used. Common specimen tests include:

  • Breath
  • Blood
  • Sweat
  • Urine
  • Hair Testing
  • Fingernail
  • Saliva
  • Breast Milk

Testing Window

  • Breath (remote alcohol monitoring) – as long as required
  • Blood indirect (CDT, LFT, FBC) – 30 days
  • Blood direct (PEth) – 30 days
  • Fingernail – 3-6 months
  • Head hair – 0-3 or 0-6 months
  • Body hair (chest, arm) – 4-8 months
  • Body hair (pubic) – 4-8 months
  • Saliva – 24 hours
  • Breast Milk – 30 days
  • Sweat – 80 hours

Indications of Various Testing Specimens

It is possible to assess the drinking habits of the individual through alcohol tests. According to the level of alcohol content in the specimens, here are some of the indications:

  • Breath (Remote alcohol monitoring) – social drinking, alcohol abuse, abstinence
  • Head hair – social drinking, alcohol abuse, abstinence
  • Body hair (chest, arm) – social drinking or alcohol abuse
  • Body hair (pubic) – Abstinence
  • Fingernail – alcohol abuse, social drinking
  • Urine – social drinking, alcohol abuse
  • Saliva – Social drinking, alcohol abuse
  • Blood direct (PEth) – social drinking, alcohol abuse, abstinence within a week
  • Blood indirect (CDT, LFT, FBC) – Alcohol abuse or abstinence with a limitation of 44-85% accuracy

Common Tests for Alcohol Detection

The common alcohol testing methods are blood, breath, and saliva tests. There are other specimens like hair, nail, sweat, and breast milk tests as well. These tests help in diagnosing the drinking habits or abstinence from alcohol by a person. Below are brief notes on each type of alcohol testing.

Hair Testing

Testing head-hair samples is an accurate way to verify the alcohol consumption habits of an individual up to 3 to 6 months.

Hair testing is mainly of two types, such:

  • EtG (Ethyl Glucuronide)
  • FAEE (Fatty Acid Ethyl Esters)

The testing window for hair testing depends on the length of the hair. Hair with a minimum 3cm length offers 3 months and 6cm for 6 months detection window. However, testing hairs below 3cm in length reduces the alcohol detection period to below three months.

Always combine EtG hair testing with blood tests to get more accurate results. Similarly, FAEE testing is best for chemically treated hairs like bleached or dyed hair.

Blood Testing

Blood testing is a proven clinical option to detect potential alcohol abuse by an individual.

Alcohol can be detected in blood for up to 36 hours by using the EtG test. But the most accurate results of alcohol in the blood are detectable between 6 to 12 hours after the last drink.

Bothe indirect or direct biomarkers may be used in various types of blood tests, such as:

  • Full Blood Count (Mean Conspicuous Volume – MCV) – Indirect
  • Liver Function Test (LFT) – Indirect
  • Phosphatidyl Ethanol (PEth) – Direct
  • Carbohydrate-deficient Transferrin (CDT) – Indirect

Fingernail Testing

Fingernail testing is a suitable alternative to hair testing.

EtG (Ethyl Glucuronide) works well in nail tests.

The metabolites of drugs and alcohol travel to blood vessels located under the nail. There they are trapped within keratin fibers.

Nails can hold more metabolites than hair because of their thickness and volume.

It is possible to trace the elements of alcohol in nails for a period of 3 to 6 months. Growth, length, and frequency of trimming the nails influence the detention period.

Unfortunately, there is little clarity on which segments of the nails are relevant to such tests.  There is a serious shortage of studies and clarity on nail testing.

Urine Testing

One of the common tests for alcohol in your system is urine testing. The detection period varies according to the testing tools.

Ethanol Urine Testing

Ethanol is the alcoholic content in alcohol. The liver breaks down ethanol and dispels the metabolized ethanol through urine, sweat, and breath.

Ethanol urine tests can effectively detect the presence of ethanol in the urine.

Tests can easily detect ethanol in urine between 2 to 12 hours after having the last shot of drinks.

An ethanol urine test can go wrong for some reason such as:

  • if your urine is left out at the room temperature
  • urinary tract infections
  • diabetes effects
  • yeast infection

EtG Urine Test

Ethyl glucuronide, or EtG, is a substance generated when the liver breaks down alcohol. EtG stays in the body for a longer time than ethanol.

The detection window for EtG is from 8 hours to 80 hours after the last drink.

EtG tests do not clearly indicate the timing of alcohol; not useful in examining cases such as DUI and DWI.

Breath Test

The alcohol breath test is the most common type of alcohol test. It is a very handy testing method used by the traffic police to detect DUI.

You can find different types of breath tests for alcohol detection. All of them measure the amount of alcohol in your breath. They all indicate the amount of alcohol present in your bloodstream.

A breath test works best 15 minutes after drinking or one minute after smoking.

A breathalyzer detects the level of blood alcohol concentration. A breathalyzer test can be positive for up to 12 hours after the last drink.

Saliva Test

EtG test can detect alcohol in saliva from 1 hour to 24 hours after drinking. On the weaker side, this test does not indicate the level of alcoholic content in the body.

Breast Milk Test

Drinking is not a good option for nursing mothers. After a drink, the breastfeeding mothers should wait for at least two hours before nursing or pumping. Pumping and dumping don’t immediately get rid of the alcohol in your breast milk.

Alcohol levels peak in the milk anywhere from 30 to 60 minutes after a drink. The alcohol stays in the breast milk for 2 hours to 12 hours.

The Bottom Line

Different alcoholic drinks like wine, beer, and liquor break down differently in each person’s body. Therefore, the detection period for each type of drink and other biological factors influence the outcome of alcohol tests.

The most commonly used alcohol tests are breath and urine tests. However, hair or fingernail tests offer a longer detection window for alcohol testing. Blood and saliva tests offer only a shorter detection period, less than 48 hours at the most.

Article Source:


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