Frequently Asked Questions

More information on Hair Drug and Alcohol Testing, DNA Relationship Testing and SCRAM™ Continuous Alcohol Testing.

To view the answer, please click on the question.

Hair Drug Testing

What time period can a hair drug test cover?

Hair grows at an average rate of 1cm per month. Therefore a 3cm section of head hair will provide an approximate time period of 3 months. The time period that a hair sample can cover is dependent on the length of hair that is available. If someone was to have 12cm of hair, then a hair drug test could cover the past year. Providing there is sufficient hair, a hair drug test can cover a period of months rather than days that oral fluid and urine analysis can provide.

Can body or facial hair be used if no scalp/head hair is present?

If no scalp hair is available, then body hair or facial hair can be used. Body and facial hair grow at the same average rate of 1cm per month, however it has a different growth cycle to that of scalp hair, meaning that a greater proportion of the hair remains on the body or face in its resting or telogen phase. For this reason, body or facial hair samples are analysed as a whole sample and are unable to be segmented into a month by month analysis.

What’s the difference between a month by month analysis and an overview?

A month by month analysis will section the hair into approximate individual months covering the length of the hair that requires analysis. For example, if a hair drug test was to cover 6 months, a month by month analysis will provide 6 individual results for each approximate monthly period. This is especially useful if you need to obtain a trend in drug use, i.e. to see a decrease or increase in drug use over time, or highlight particular months where drugs were or not used.

An overview of a 6 month drug test will provide you with 2 results, one for the first 3 months and a second result for the second 3 months. Therefore the overview analysis will provide a general result of drug use within a 3 month time period, and not to an individual month. An overview analysis is beneficial if you only need to obtain a general indication of drug use or abstinence.

What drugs can you detect?

Visit our Hair Drug Testing page to read our Drug Detection List.

How soon after a drug was taken can it be detected in the hair?

It takes about 2 weeks from the time of drug use to it being able to be detected in the hair. This is due to the time it takes for the hair to grow a sufficient length to be cut and analysed. To detect more recent drug use we recommend an oral fluid drug test that will show up to a maximum of 2-3 days.

How quickly can I receive the results of a hair drugs test?

We aim to issue the results, in the format of an expert report on average within 5 working days of receiving the sample into our Cardiff laboratory. We use the latest technology to provide a fast and efficient analysis time.

Hair Alcohol Testing

What are Ethyl Palmitate (EtPa) and EtG?
Ethyl Palmitate (EtPa) and EtG are metabolites (by products) produced by the body after the consumption of alcohol. For this reason Ethyl Palmitate (EtPa) and EtG are suitable biomarkers for the detection of alcohol in hair when trying to asses chronic excessive alcohol use.
What are the differences between Ethyl Palmitate (EtPa) and EtG? Why should both be used together?
Ethyl Palmitate (EtPa) is produced in the blood and EtG is produced via the liver. Both are by products of alcohol use during the metabolism of alcohol. EtG is soluble in water and as such is susceptible to be leached out of the hair through normal hygiene practices or through the use of cosmetic treatments (hair dyes). Ethyl Palmitate (EtPa) is not soluble in water, however are still sensitive to hair treatments.

Ethyl Palmitate (EtPa) and EtG are different biomarkers that when used together can provide a greater degree of confidence when assessing an individual’s chronic excessive alcohol consumption. Either test may be used in isolation, however this rules out the mutual confirmation of results.

Lextox has taken guidance from the Society of Hair Testing Consensus for the Use of Alcohol Markers in Hair for Assessment of Chronic Excessive Alcohol Consumption and provides Ethyl Palmitate (FAEE) and EtG analysis as a combined test as standard for the mutual exclusion of false positives and false negatives.

It is also recommended that the alcohol in hair test is used in conjunction with blood alcohol tests (liver function and CDT) to help obtain a more comprehensive picture of an individual’s alcohol use.
How do Ethyl Palmitate (EtPa) & EtG get into hair?
Ethyl Palmitate (EtPa) is incorporated into the hair via sebum, an oily secretion composed of fat and wax that is produced by glands on the skin. Incorporation of EtG into the hair is mainly thought to occur via sweat.
What is classed as chronic excessive alcohol use?
Currently, the Society of Hair Testing states that chronic excessive alcohol drinking corresponds to an average consumption of 60 grams of pure ethanol (alcohol) per day over several months.

In the UK, 1 unit of alcohol is defined as 8 grams or 10 millilitres of alcohol, so 60 grams of alcohol equates to 7.5 units. The amount of alcohol consumed depends on the strength of the drink. A single shot of spirits is 1 unit, a standard glass of wine (175ml) and a pint of lower strength lager is 2 units and a bottle of wine at 12% ABV is 9 units.
Can the alcohol in hair test show alcohol abstinence?
No, the alcohol in hair test should only be used to help assess chronic excessive alcohol use.
What is the time period that an alcohol in hair test can cover?
Currently the recommended length of hair that an alcohol in hair test can cover is either the past 3 months, or the past 6 months. This is in line with the Society of Hair Testing Consensus for the Use of Alcohol Markers in Hair for Assessment of both Abstinence and Chronic Excessive Alcohol Consumption.
Can you do segmental analysis with the alcohol hair test similar to the drug hair test?
Lextox do not recommend sectioning hair samples for hair alcohol marker - EtG and Ethyl Palmitate (EtPa) - analysis into 1 cm sections for a segmented month by month analysis.

The results obtained would not be comparable to the Society of Hair Testing (SoHT) guidelines and therefore would not provide an indication of a donor’s alcohol consumption.
Can body hair be used for alcohol testing if no head hair is present?
If no scalp hair is available, then chest, leg and arm hair can be used. Body hair grows at the same average rate of 1cm per month, however it has a different growth cycle to that of scalp hair, meaning that a greater proportion of the hair remains on the body in its resting (non-growing) or telogen phase. For this reason, body hair samples are analysed as a whole sample and are unable to be segmented into a month by month analysis.
Can bleaching or dyeing the hair affect the levels of alcohol markers detected?
Both Ethyl Palmitate (EtPa) and EtG are sensitive to the use of cosmetic treatments such as hair dyes and hair bleach. Our experts are on hand to provide guidance and advice on chemically treated samples.
Do the levels of Ethyl Palmitate (EtPa) and EtG detected in the hair sample equate to units of alcohol consumed?
Due to the difference in people’s metabolism, hair growth rates and difference in hygiene practices, it is not possible to correlate the amount of Ethyl Palmitate (EtPa) and EtG detected in the hair to specific units consumed. The alcohol in hair test identifies the biomarkers that are produced by the body when alcohol is used as opposed to identifying the alcohol itself.

Blood Alcohol Testing

How long will the blood alcohol results take?
The blood alcohol results for LF and CDT tests will take 5 workings days from receipt of the sample into our laboratory. Analysis results for PEth testing will take up to 10 working days from receipt of the sample into the laboratory.
What time period can blood alcohol testing cover?
The blood tests for alcohol show recent alcohol use. A liver function test is a snap shot in time of the liver function and damage, whereas a CDT test can highlight excessive alcohol consumption over the past 2-4 weeks.

PEth blood testing is useful in detecting prolonged or heavy ‘binge’ drinking, when tested for regularly. Typically, the detection period for PEth is 4 weeks. PEth can remain in blood for as long as 4 weeks.
Why are LF and CDT testing used in conjunction?
It is recommended that both liver function and carbohydrate deficient transferrin tests are used together to obtain a better picture of alcohol use. Each test looks for different markers so when combined together they can provide mutual confirmation and a greater degree of certainty. A single test in isolation may lead to a misinterpretation of alcohol use.
What is PEth Testing?
A PEth blood test measures the level of phosphatidylethanol, a direct alcohol biomarker which is found in human blood following alcohol consumption. Phosphatidylethanols are abnormal phospholipids formed in the presence of ethanol (more commonly known as alcohol). PEth is formed in the presence of ethanol and bonds to the membrane of red blood cells.
Who can take a blood sample?
Blood samples can be taken by our collectors or by a medically trained professional.

DNA Relationship Testing

How quickly will I receive the test results?
Our average turnaround time for analysis results is three working days or less. Please note that analysis results for prenatal DNA tests will be provided in 8 working days or less.
I'm unsure as to which test I require to fit the circumstances, what should I do?
Talk to our Experts today and they will advise you on what types of tests we offer and how they can be beneficial to you/your case - or 029 2048 4141.
How are the DNA samples taken?
The samples are taken by one of our professionally trained healthcare specialists. A forensic swab is used to brush the inside of the donor's cheek, in what is a painless and non-invasive procedure.
From what age can a child be tested?
Due to the fact that our testing is conducted through analysing buccal swabs (which are completely pain-free and non-invasive to collect) we are therefore able to test a child of any age after birth.
What is 'Peace of Mind' testing and do you offer it?
Yes we do. Peace of Mind paternity testing, also called private or in-home paternity testing, is characterised by the self collection process. We send sample collection kits to the tested parties, and they perform their own buccal swabbing to collect their DNA samples. Because of this collection method, private paternity testing produces results that are not legally defensible. Included with the kit are consent forms that must be signed and returned with the samples.

SCRAM Continuous Alcohol Testing

How does SCRAM test an individual’s alcohol consumption?
The bracelet tests the level of alcohol excreted transdermally (through the skin) of the donor.
Are you able to detect whether the bracelet has been obstructed and/or tampered with?
Yes. The bracelet is fitted with both temperature and infrared sensors which are able to detect when an object has been placed in between the ankle and the sensor.
Do Lextox fit/install the SCRAM bracelet?
Yes. One of our professionally trained Sample Collectors will meet you at your location to install the SCRAM Base Station and to fit the bracelet to the participant's ankle.
For how long does the SCRAM bracelet need to be worn?
Individuals will typically wear the bracelet for 30, 60 or 90 days as standard. However the length of time can be tailored to suit your requirements.
How disruptive is wearing the SCRAM bracelet to day to day life?
The beauty of the SCRAM bracelet is that it causes very minimal disruption to an individual’s day-to-day life. They are still able to shower, work out, go to work and spend time with friends and family as normal.
Does the Base Station require a phone line in the participant’s home?
No. There are multiple ways to connect the Base Station and for readings to be transmitted including - landline, ethernet (internet connection through the donor's router) and wireless multiconnect unit.
How does the Base Station gather alcohol readings from the participant?
The information is transmitted to the Base Station wirelessly twice a day. If the donor is not in range of the Base Station, the device will still gather information and will transmit readings when the participant is back in range of the Base Station.

Sample Collections

What sample types can the collectors take?
Our professionally trained sample collectors are able to take hair, blood and oral samples from donors all within one sample collection appointment ensuring convenience to you and the donor. All our collectors are fully trained in the chain of custody procedures and sample collection to ensure the sample is taken correctly to prevent analysis delays.
Can the collectors take body hair samples?
Our collectors are able to take hair from the underarm (axilla), chest and leg as well as pubic hair.
What ID documentation will the donor need at the time of the sample collection?
The donor needs to be able to prove their identity at the time of the sample collection to ensure that we are collecting the sample from the correct person. A driving licence, passport or another form of photographic ID will be required.
How much hair will be taken?
We require a minimum weight of hair to successfully undertake drug and/or alcohol analysis. If the hair sample falls below our recommended weight, the sensitivity of the test may be compromised.

For drug analysis we require a minimum of 10mg per section. For alcohol analysis, a minimum of 20mg per alcohol marker.

Due to the nature of hair testing, samples have to be collected as close to the scalp as possible. Our sample collectors are fully trained to collect sufficient sample while minimising the impact on the donor. This includes cutting the hair with scissors and where possible taking it from the crown of the head to allow the remaining hair to cover the sample site.
What should our clients do to prepare the donors for the hair sample collection?
It is helpful when the donor is made aware of the samples that are being collected and the reasons why. This helps to prevent any distress for the donor and allows the sample collection to run smoothly.

Usually, two hair samples are collected from the scalp, each approximately a pencil width of hair, from the crown of the scalp. There are cases where more hair may be required as the weight and texture of hair varies from one individual to another. If the hair is being tested for Spice, psychoactive substances or steroids, more samples need to be collected. In cases involving body hair, the sample sites will vary depending on the type of analysis that is required.

Our sample collectors are fully trained and understand the importance of collecting sufficient hair samples to undertake the requested analysis. Due to the nature of the analysis, we require a minimum weight of hair to successfully undertake the requested testing.

The weight of the hair sample is only obtained by accurately weighing the hair at our laboratory using very sensitive, accurate and calibrated scales. Our sample collectors are not able to establish the actual weight of the hair sample at the time of the sample collection.

We recommend that all donors provide prescriptions, details of medications and hair products used at the sample collection appointment, which ensures that such items are taken into consideration in the Expert Report. This helps to avoid delays with the testing and also reduces the need for questions regarding medication/hair products after the analysis has taken place.
With regard to blood samples, it is recommended that the donor is asked to keep hydrated before a blood sample is collected.