Lab Test Alcohol: Definition, Types, and Results
19 September, 2023
A laboratory or lab test for alcohol is the examination of biological specimens to determine the presence of alcohol molecules. It involves collecting urine, saliva, hair, or blood samples and testing them for alcohol concentration. The results can help diagnose whether an individual has been abusing alcohol, measure their intoxication, or monitor their treatment progress. These methods have various criteria for accuracy depending on the type of sample and the testing device used.
Alcohol consumption is a prevalent social activity in many cultures around the world. However, excessive intake or irresponsible drinking can have severe consequences on one’s health and well-being. It is one of the leading causes of road and workplace accidents. Thus, medical professionals rely on laboratory procedures to assess levels of alcohol in a person’s system accurately. In this article, we will explore the functions of the purpose of laboratory testing, its types, and understanding of the results.
What is a Lab Test for Alcohol
There are several forms of alcohol testing. The first type is screening, where it utilises immunoassays to detect the presence of alcohol in a sample. Immunoassays are quick and convenient. This type of testing gives qualitative results, such as negative or non-negative, indicating alcohol use. The screening tools can be used on-site in workplaces or remote areas.
On the other hand, a lab test for alcohol uses advanced technology and equipment to measure and give quantitative results. It measures the amounts of alcohol in the sample. This type of testing is more accurate than screening as it can trace the precise Blood Alcohol Concentration (BAC) levels. It is used when the initial tests return a non-negative result.
The most common methods of laboratory techniques are gas chromatography, mass spectrometry, and enzymatic assays. Tests for acute alcohol ingestion include ethyl glucuronide (EtG) and ethyl sulfate (EtS). Moreover, carbohydrate-deficient transferrin (CDT) and phosphatidyl ethanol (PEth) are direct biomarkers of alcohol consumption. It is useful for determining chronic alcohol use or monitoring abstinence.
Why Conduct the Test
- Measure a person’s exact blood alcohol level for medical or legal purposes. The results can be used as evidence in court in drink driving and probationary cases.
- Help healthcare professionals diagnose whether someone is struggling with alcohol use disorder.
- Confirm a preliminary screening to eliminate the possibility of false positives.
- Identify if excessive alcohol consumption is related to liver damage in patients and other medical conditions.
- Check if heavy drinking is a factor in an accident or injury.
- Monitoring patients in alcohol treatment programs. It ensures that individuals avoid relapse and stay on track with their recovery.
Types of Lab Tests for Alcohol
Lab tests for alcohol employ several types based on the given sample. A common type is the urine test. It analyses urine samples for the presence of direct or indirect biomarkers. An advantage of alcohol urine tests is they can trace alcohol metabolites, like ethyl glucuronide, for an extended period long after the body has processed ethanol.
The second type is oral fluid testing. It examines the saliva for alcohol using liquid chromatography-mass spectrometry (LC-MS) techniques. Moreover, saliva samples can detect alcohol up to 24 hours after consumption. Hence, it can provide a reliable estimate of the blood alcohol content for recent use or impairment.
Furthermore, blood tests provide the highest accuracy among the alcohol test methods. Blood samples can detect alcohol for up to 12 hours. It is useful in diagnosing alcohol poisoning or heavy drinking. Lastly, hair alcohol testing can trace alcohol metabolites stored in the hair strands for up to 90 days. It is suitable for determining possible alcohol use disorder, as it can reveal a person’s long-term consumption patterns or history.
How to Prepare for a Test
Preparing for a laboratory test for alcohol requires a few steps. It is important to follow a doctor’s instructions to ensure accurate findings. Generally, it is advisable to abstain from consuming any alcoholic beverages for at least 24 hours before the test. This is crucial as alcohol can quickly metabolise in the body and stay in the system for a few hours.
The second measure is to stay hydrated and drink plenty of water. It is also vital to disclose any medications or health conditions that may affect the results. Lastly, avoid using mouthwash or exposure to alcohol-containing products to minimise false positives.
Understanding the Results of a Lab Test for Alcohol
The results of a lab test for alcohol depend on the type of sample, method used, and cut-off values. The cut-off values are pre-determined threshold concentrations. It helps differentiate between positive and negative test results. A confirmed positive result indicates the presence of alcohol in the sample. In contrast, negative results mean that no alcohol was detected.
Lab tests can provide quantitative data regarding the amount of alcohol or level of intoxication. Alcohol testing often measures the BAC or percentage of alcohol in the blood. It is computed by the volume of ethanol in grams for every 100 ml of blood. The higher the BAC level, the more severe the alcohol intoxication or impairment. At extremely high levels, it can lead to alcohol overdose.
BAC is the standard unit of testing for alcohol in various settings. Law enforcement checks the drivers’ alcohol levels to see if they are legally intoxicated. The legal limit in Australia is 0.05%. Exceeding this limit in evidential alcohol testing is subject to legal penalties, including fines, license disqualification, imprisonment, or alcohol interlock.
Potential Risks of Testing in the Lab
Laboratory tests are generally reliable. However, all testing methods, including laboratory analysis, are prone to errors or inaccuracies. Firstly, incorrect handling of the specimen and storage may cause false positives. Secondly, the time elapsed from the sample collection to transportation to a medical facility plays a critical factor in the result.
Finally, laboratory technicians must observe protective gear to prevent contamination. Improper techniques or uncalibrated instruments may lead to inaccurate results. A Medical Review Officer can verify that a positive result is due to alcohol ingestion and not incidental exposure. Therefore, it is vital to ensure proper collection techniques to avoid invalid tests.
Lab test for alcohol is an important tool for measuring the concentration of alcohol in a person’s body. It utilises various testing methods to detect ethyl alcohol and its metabolites, such as urine, saliva, hair, and blood. The first step involves screening, which uses immunoassays to detect substances. Then, if the results indicate alcohol use, the samples undergo advanced testing for confirmation. The results are useful for evaluating heavy alcohol consumption or abuse problems.
Moreover, certain types of tests can trace specific alcohol biomarkers. Thus, it can provide a more accurate picture of a person’s health condition or drinking habits. Furthermore, individuals must follow the guidelines for preparing for the test. Lastly, it is critical to use correct procedures to minimise inaccurate results. Therefore, these tests play a crucial role in law enforcement, workplace testing, and other situations where alcohol use needs to be monitored.