BAC Lab Test: What Are The Various Procedures?
09 November, 2023
The Blood Alcohol Concentration (BAC) is the percentage of ethanol in the bloodstream. A BAC lab test is a helpful tool used by law enforcement agencies, employers, and healthcare providers to determine the level of alcohol intoxication. Several testing methods are used for measuring alcohol consumption, such as urine, oral fluid, hair and blood testing. These help identify those with alcohol abuse problems for early intervention. In addition, the results of tests may serve as evidence during legal proceedings.
Alcohol Use Disorder (AUD) is a medical condition that affects many. The effects of alcohol misuse affect various aspects of life. Excessive alcohol consumption may lead to impaired judgment, slow reaction times, and double vision, which leads to accidents. Thus, it is crucial to identify intoxicated individuals to prevent them from causing harm. This article will present the various procedures for alcohol testing, such as urine, oral fluid, blood, and hair tests.
BAC Lab Test Using Urine Analysis
A BAC lab test using urine samples is considered the standard for workplace testing. Urine tests have a detection window of up to 24 hours. During this period, lab technicians may find traces of alcohol, medication, and illegal drugs. Excessive alcohol and drug consumption may increase the accuracy of the results. However, people must follow guidelines to avoid contamination.
Furthermore, ethyl glucuronide (EtG) tests increase the detection window for up to 80 hours. EtG is a direct biomarker of ethanol and increases after people consume alcoholic drinks. Using urine tests, workplaces may identify those violating their substance use policies. This is key for high-risk industries with safety-critical positions where accidents may cause injuries or death.
Generally, EtG tests have a 70% accuracy, which increases heavy alcohol consumption. However, this may vary from person to person. This is because some individual and environmental factors may also affect the results and cause false positives. Some medical conditions like diabetes and exposure to items with trace amounts of alcohol may contribute to false positive results.
Sample Collection Guidelines to Avoid Contamination
It is crucial to follow the instructions of a healthcare professional when collecting a urine sample. These are some guidelines to help avoid contamination:
- Ensure the container is sterile.
- The individual must wash their hands before collection. They may also clean their genitals, if possible.
- They may collect a first catch or mid-stream sample, depending on the advice of a medical professional.
- A first-catch sample means the first part of the urine that comes up. Meanwhile, a mid-stream sample refers to the urine, excluding the first and last part.
- Screw the lid of the container tightly and securely.
- Label the container properly to avoid confusion.
BAC Lab Test Using Oral Fluid
A BAC lab test using oral fluid samples is typical during onsite testing. This type of test requires using a swab stick to collect saliva samples from under the tongue or inside the cheek. Afterwards, the sample is sent to a laboratory for analysis. This screening method has a detection window of 12 hours. Many workplaces and police officers also use this testing method.
Like other tests, saliva screenings use cut-off levels to help prevent false positives. However, certain factors may affect the detection period of ethanol in saliva. This includes age, body weight, hydration levels, and the amount of time that has passed since the last consumption of alcohol.
Laboratories may use various methods to find alcohol metabolites. Enzymatic assays are typically used to identify enzymes and measure their activities. Furthermore, they may also use specialised methods like gas chromatography-mass spectrometry (GC-MS). This method heats the sample and uses gas chromatography to separate the compounds and mass spectrometry to classify the ions based on their mass-to-charge ratio.
Advantages of a Saliva Test
Saliva tests are commonly used because of their convenience. There are many advantages to using these tests. Firstly, it is more difficult for individuals to tamper with an oral fluid screening. This is because the collection personnel can witness and conduct the collection procedure.
Secondly, it is less invasive than other lab testing methods and does not require the use of toilets. Thirdly, this type of test is easy to conduct publicly because of its simple collection method. Lastly, it has a short collection time, enabling many people to be tested in a short period.
BAC Lab Test Using Hair Follicle and Blood Samples
A BAC lab test using hair strands provides a detection time of 90 days. This is often used to trace a history of substance use. However, it does not include substances seven days before collection due to the nature of hair growth. The collection procedure involves acquiring 100 to 200 hair strands, preferably from the scalp. These samples are cleaned and taken to a laboratory for analysis. Like urine testing, this also uses EtG markers to determine alcohol consumption.
Meanwhile, blood tests are considered the most accurate method of screening. Typically, these detect drugs and ethanol consumed within 12 hours. However, using carbohydrate-deficient transferrin (CDT) and Phosphatidylethanol (PEth) tests, the detection period for ethanol increases to weeks before collection. These are often used by law enforcement for legal testing because of their accuracy.
However, it requires an invasive procedure to collect blood samples. Typically, blood is drawn from the arm using a needle by a health professional. However, for PEth tests, small amounts of blood from the fingers will suffice.
Utilising a Breathalyser as a Non-invasive Alternative
A breathalyser is a device used during breath tests to measure the BAC levels of an individual. It may detect traces of alcohol consumption for up to 24 hours. This device uses sensors to create chemical reactions to produce small electrical currents that reflect the amount of alcohol in the breath sample. It is a quick and non-invasive way of testing BAC levels.
Furthermore, individuals may use personal breathalysers in various settings. To use this, the person must attach a mouthpiece to the device and blow into it until it signals them to stop. Afterwards, the results will appear.
A BAC lab test is a helpful tool for measuring alcohol consumption. This helps identify those with AUD and provides them with resources for rehabilitation. Furthermore, they help police officers assess if drivers are following the legal limit for alcohol intake. Using urine, hair, saliva, and blood tests, various industries may keep their workplaces safe and ensure their employees are capable of handling their jobs.
Laboratories use specialised methods, like GC-MS, to ensure the accuracy of results. However, certain factors may result in false positives. This is why confirmatory testing is also beneficial, and many recommend diversified testing. Another option for measuring BAC levels is using breathalysers. These are convenient devices that only require breath samples to measure BAC. It is non-invasive and provides accurate results. Some may benefit from owning BACtrack breathalysers equipped with police-grade sensors to help monitor their alcohol intake.