This page contains the most frequently asked questions regarding our products and services. If you can't find the answer you are looking for please contact us.
Hair Drug Testing
You should choose a hair drug test:
- When you need a window of detection that covers months
- When you need to identify a trend of drug use over a long term period, without providing multiple samples for analysis
- When you need a legally defensible drug test, with observable sample collection
You should not choose a hair drug test:
- When you need to know if someone has taken drugs in the last 2 weeks
- When you need a continuous timeline of drug use measured in days not in months
Each hair follicle has its own blood supply, which provides the hair with nutrients to grow. When a drug is taken, it is absorbed into the blood stream and circulated around the body. As the hair grows, drugs from the blood supply are incorporated into the hair shaft.
Hair on the scalp grows at a rate of approximately 1 centimetre a month which means that each 1cm section of hair provides approximately a 1 month profile of drug use.
This allows us to cut a longer sample of hair into 1cm sections for a more detailed month-by-month profile of drug use.
An overview analysis looks at a two or three months as a whole, for which we cut the sample into 2cm or 3cm length sections, as requested. This will indicate which drugs have been taken over an approximate 2 to 3 month period per section. Consecutive 3 month periods can be analysed to provide a profile of drug use over a long term period. For example, for a year-long analysis, 4 separate 3cm sections will be analysed, and a result provided for each.
A month-by-month analysis will look at each month individually. Within our laboratory we have a team dedicated to hair preparation that will cut the sample in 1cm sections (each 1cm section represents approximately 1 month) and each section is analysed and reported individually. A month-by-month analysis is especially useful when assessing trends of drug use for a donor or when a more precise chronological profile of drug use is required.
No. Although we normally test head hair, if the donor has a shaven head or is bald, we can also test hair from the face, armpit, chest, leg, arm, back, shoulder or pubic area.
No, this is not something we recommend or a service we provide. By taking a sample from a brush it is impossible to confirm whose hair it is, how old the hair is, and if the donor has consented to the testing.
Yes. However due to the nature of dreadlocked hair it may contain much older strands of hair compared to non-dreadlocked hair. This means it is not possible to accurately determine the period of drug use.
Yes. However due to the nature of Afro-Caribbean hair it is more difficult to give an approximation of the time period the sample covers. Once we have received the sample we can advise whether or not the sample can be sectioned for a month-by-month analysis or if it should be tested as a whole sample length.
Yes. However as the hair growth cycle and rate differs in children we will not proceed with the testing without a consultation first.
We wash all hair samples prior to analysis to safeguard against external contamination however chemical treatments such as hair dye, bleach, chemical straightening and permanent waves can damage hair.
This may lead to drugs leaching out of the hair which makes it harder to detect low drug use. More frequent use can still be detected but the concentration of the drug(s) may be lower than that in untreated hair.
An Expert Witness Report is recommended for test results that are required for court proceedings. A detailed explanation of the results, from a laboratory that handles thousands of samples each year can ensure that you have reliable and robust test results which can stand up to court examination.
Hair Alcohol Marker Testing
Our overview analysis looks for the presence of two markers of alcohol: ethyl glucuronide (EtG) and the fatty acid ethyl ester (FAEE) ethyl palmitate to determine chronic excessive alcohol use.
A chronic excessive alcohol user is defined within the 2016 Consensus for the Use of Alcohol Markers in Hair for Assessment of both Abstinence and Chronic Excessive Alcohol Consumption [pdf 32KB] as an individual who consumes an average of 60g or more of pure ethanol per day (7.5 units per day) over several months.
Although we can test for the last 6 months in line with the Consensus of the Society of Hair Testing we strongly recommend that a 3 month period is used. This is because the wash out effect of EtG is more common for lengths over 3cm and a negative result is more likely.
Head (scalp) hair is the preferred option for alcohol marker testing, as recommended by the Society of Hair Testing. If scalp hair is not available, and body hair is to be used, we recommend the testing of chest hair. However, if neither scalp hair nor chest hair is available then hair from other sites of the body, with the exception of underarm (axillary) and pubic hair, can be submitted for testing. Studies have shown that underarm hair and pubic hair samples are not suitable to use for alcohol marker testing.
No. Hair alcohol marker tests are looking for chronic excessive use and should not be applied when trying to determine abstinence, binge or social drinking. Whilst a positive hair test for both alcohol markers (EtG and the FAEE ethyl palmitate), corroborated with blood tests, are supportive of a diagnosis of chronic excessive alcohol use, normal hygiene practices and the impact of hair treatments mean that negative hair alcohol tests do not necessarily indicate low alcohol use or abstinence.
If you are trying to provide evidence of sobriety we recommend that SCRAM CAM® is used. The ankle bracelet tests a person for alcohol every 30 minutes, covering an entire 24 hour period, providing non-invasive, automated testing.
Yes. Unlike testing hair samples for drugs it is not yet possible to rule out the effects of normal hygiene practices such as shampooing when analysing for evidence of chronic excessive alcohol consumption over a period of months. The use of products on the hair, containing alcohol could contribute to the level of the fatty acid ethyl ester (FAEE) ethyl palmitate detected.
We conduct two blood tests to detect markers of possible chronic excessive alcohol consumption:
Liver Function Test (LFT)
A LFT measures various chemicals in the blood that are produced by the liver. An abnormal result indicates a problem with the liver, and can reflect damage caused by excessive alcohol use. Changing levels can also be caused from other medical problems outside of the liver and some medications.
Carbohydrate Deficient Transferrin (CDT) Test
A CDT test looks at transferrin, a protein that transports iron around the body, which is affected by drinking alcohol. The effect takes the form of a deficiency of carbohydrate (sugars) attached to the protein. The level of deficiency is reported as a percentage (%). A reading of over 1.6% would be considered positive and would be consistent with an increased alcohol intake within the previous 2 to 4 weeks.
A LFT can highlight liver damage caused by long term excessive alcohol consumption, whilst a CDT offers higher specificity related to recent heavy alcohol consumption.
A professional interpretation of the blood results will contribute to understanding whether or not alcohol misuse is an issue in care proceedings. This includes a detailed explanation of the biochemical markers tested and an interpretation and clinical review of the results.