Concateno plc - global drug testing services

 

FAQs

 Hair Testing
• Which drug test should I use? How do I decide which is best for my case?
• What is the time period a drug test covers, and what variations can I request?
• What is a month-by-month or overview analysis?
• When should I choose a hair test?
• When should I NOT choose a hair test?
• Can external contamination affect the results?
• Can dyeing or bleaching hair affect the detection of drug use?
• I have read that cannabis cannot be detected in hair. Is this true?

Hair Samples
• How much hair is needed for a test?
• What if the donor has little or no head hair?
• What are my options for sample collection?

General Drug Testing
• How accurate are drug tests?
• Can passive smoking have an effect on results?
• Can you detect the difference between over-the counter drugs and illegal substances?

•  What drug groups can you test for?

• What is an Expert Witness Statement?

• What drug groups should I select to test for?

Alcohol Testing
• Why is the time period capped at 3 months for a EtG test?
• Why is only a month-by-month analysis used?
• Why use a combination of tests?
• Why can body hair not be used as a sample?
• Why are Expert Witness Statements not available for Liver Function & Carbohydrate Deficient Transferrin tests?

Research
• Do hair tests discriminate between fair haired and dark haired people?
• What studies have been published on hair testing?

Hair Testing

Which drug test should I use? How do I decide which is best for my case?
Decide on what the purpose of the tests is – do you need a detailed analysis covering of a series of months? Or has there been a previous test and another one is being taken to prove abstinence, for which an overview would suffice? We have a team dedicated to providing an professional opinion on which type of test best fits your purpose. Our company policy is to be honest about the limitations of each sample type and method - none of them are perfect - so you have the information with which to make a decision.

What is the time period a drug test covers, and what variations can I request?
A drug test can cover periods of months or years depending on the length of the hair sample available. 1cm of head hair will cover approximately a 1 month period of time. Therefore, hair 12cm in length will provide approximately a one year profile of drug use. The window of detection is entirely dependent on the length of hair available, although for particularly long windows of detection (for example, longer than 12 months) we would recommend that you discuss the potential strengths and limitations of such an analysis with one of our Reporting Scientists so that the most effective analysis for your case can be identified. We offer hair tests as a month-by-month or overview analysis.

What is a month-by-month and overview analysis?
A month-by-month analysis will look at each month individually. A team dedicated to hair preparation based in our laboratory, will cut the sample in 1cm sections (each 1cm section represents approximately one month) and each section is analysed and reported upon 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.

An overview looks at a two or three month time period as a whole. We cut long samples into 2cm or 3cm length sections, in order to maintain the test's sensitivity. This will indicate which drugs have been taken over an approximate two to three month period. Consecutive three 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.

When should I choose a hair test?
• When you need a window of detection that covers months or more
• 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

When should I NOT choose a hair test?
• When you need to know if someone has taken drugs in the last 24 hours - 3 days
• When you need a continuous timeline of drug use measured in days not in months
• If you need to identify a particular day or weekend that a drug was taken. A hair test can show in which month a drug was used (when using a month-by-month analysis), but not a more specific time period

Can external contamination affect the results?
Scientists at our laboratory wash the hair samples prior to analysis as an additional safeguard for donors. We can (if requested) also analyse the wash solution to determine whether any drugs were found on the exterior of the hair sample. We also test for metabolites (substances produced by the body only when specific drugs have been used) in addition to drugs. If we detect the presence of the metabolites associated with a particular drug, this is an indication that the drug in question has entered the body. Finally, we also employ cut off levels on our analysis. Cut offs are the levels at which a drug needs to be detected in order to trigger a ‘detected’ result. A positive result from external contamination is unlikely due to the level our cut off levels are set at.

Can dyeing or bleaching hair affect the detection of drug use?
Chemical treatment of the hair such as hair dye, bleach, chemical straightening and permanent waves can damage hair. This damage may lead to some of any drugs that may be present, being leached out from the hair, and therefore treated hair may hold less drug than if the hair had not been treated. As a result, it is possible that low or single use of any drugs may not be detected. More frequent use of drugs can still be detected but the concentration found may be less than that detected in untreated hair.

I have read that cannabis cannot be detected in hair. Is this true?
No. Cannabis is certainly more difficult to detect in hair but for some years Concateno TrichoTech has been developing techniques that have steadily increased the sensitivity so that we can now reliably determine the presence of cannabis constituents in hair. We test for the main psychoactive delta-9- constituent of cannabis, tetrahydrocannabinol (THC) and two metabolites of THC, 11-hydroxy-delta-9 THC and 11 nor-delta-9-THC-9-carboxylic acid. These latter two metabolites are produced by the body when cannabis has been used.

Hair Samples

How much hair is needed for a test?
About 75-150 strands are required from the head for an drugs test, equivalent to about the width of the tip of a shoe lace. About 200-300 strands are required from the head for an EtG test (alcohol in head hair), about the width of a pencil. There are approximately 100,000 strands of hair on average on a person's head, so this should not make any cosmetic difference, unless the hair is very short.

What if the donor has little or no head hair?
Even shavings from a very short ('number one') haircut can be tested, for a short term profile of drug use. If the donor has no head hair then hair from other parts of the body can be analysed – facial hair, armpit, chest or pubic hair. Someone who has shaved their head prior to a test can therefore still provide a sample. If the donor objects or has shaved all body hair , it is obviously not possible to do a hair test. However in this situation courts may make inferences from the fact that a donor has removed all of their hair. Other options in this situation are to request that the donor allows time for hair to grow (which can be subsequently analysed), or to organise continuous urine or oral fluid tests to monitor drug use.

What are my options for sample collection?
Concateno TrichoTech operate a UK-wide network of trained hair sample collectors who operate to our strict chain of custody procedures. They are able to explain the process to the donor and put them at ease. In addition, they ensure that a sample is taken promptly and efficiently (we sometimes encounter problems with insufficient samples taken by GPs), follows strict chain of custody procedures and remains independent of both parties in legal proceedings.

Drugs Test

How accurate are drug tests?
Providing the sample is genuine, a competent laboratory performs the analysis and the sample goes through two stages of screening and confirmation, the chances of a 'false positive' are very slim. Screening, the first stage in testing, does not differentiate between drugs available over the counter and illicit drugs from the same drug group. But a positive result from screening goes on to a second-stage confirmation test, using GC/MS analysis or LC/MS/MS and GC/MS/MS, and the result can clearly define which drugs were detected in the sample.

Can passive smoking have an effect on results?
It is extremely unlikely that a positive drugs test could be the result of passive smoking. Smoke from drugs inhaled by a non-drug user can deposit small amounts of that drug in their system but this is far below the cut-off levels we apply to our results in order to protect the donor from such a possibility. The hair samples are also washed prior to extraction to eliminate any environmental contamination, please see question about external contamination above for more information.

Can you detect the difference between over-the counter drugs and illegal substances?
As an example, heroin and dihydrocodeine (an over the counter remedy) have different molecular masses and different chemical structures, so they both travel through our GC-MS laboratory instrument at different rates. The analyst will identify the illegal drug from the over the counter drug, by looking at the time drugs took to travel through the GC-MS and its chemical structure. Each drug has its own unique chemical structure which is then used to identify the drug.

What drug groups can you test for?
Click here to view a list of all the drug groups we test for.

What is an Expert Witness Statement?
An Expert Witness Statement is essential 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. An Expert Witness Report details the testing procedure from sample collection through to the reporting of results, outlining the procedures in place to maintain sample integrity. They are written by our Reporting Scientists who provide a commentary on the results. If you are unsure as to whether or not you need an Expert Witness Statement please contact us on +44 (0) 2920 540 542.

What drug groups should I select to test for?
We can not conduct a ‘general test’ or for cost effectiveness do not recommend ‘asking for everything’. We are UKAS accredited to ISO/IEC 17025:2005 to detect for over 50 drugs and metabolites in hair. The nine most common drug groups which we test for are listed on our request form, although we can add more as required. If you are in doubt about what groups or drugs to request please give us a call on +44 (0) 2920 540 542 and we can advise you on the most suitable panel of drug groups to request for your case.

Alcohol Tests

Why is the time period capped at 3 months for an EtG test?
Unlike testing hair samples for drug misuse, it is not yet possible to rule out the effects of normal hygiene practices such as shampooing when analysing alcohol consumption over a period of many months. Our research in this field indicates that analysing two or three centimeters of head hair as a month-by-month analysis might provide extra information to help determine in particular if alcohol consumption has been reduced over a 2 or 3 month period. For this reason, we always perform a month-by-month analysis. Due to the effects of normal hygiene practices, we recommend alcohol in hair tests are not conducted on body hair samples.

Why do you only offer month-by-month analyses when testing for alcohol in hair?
As previously mentioned it is not yet possible to rule out the effects of basic hygiene on hair sample being tested for EtG. We therefore analyse samples for EtG using a month-by-month analysis to safeguard results against the possible ‘washout’ effect on the older sections of the sample.

Why should I use a combination of alcohol tests?
Advice from addiction specialists suggests that no single test should be used on its own to determine excessive alcohol use. A combination of an alcohol in hair test (EtG test) with blood tests (LF & CDT tests) will collaboratively offer a more dependable picture of alcohol consumption in addition to a clinical assessment from a qualified consultant psychiatrist, an addictions specialist or a GP’s knowledge of a patient’s history.

Why can body hair not be used as a sample for an EtG test?
Testing hair samples for alcohol use is still relatively new technology and it is not yet possible to rule out the effects of basic hygiene practices on the sample. We do not test body hair samples as they are most likely to be affected by basic hygiene practices.

Why are Expert Witness Statements not available for Liver Function & Carbohydrate Deficient Transferrin tests?
Blood samples that require Liver Function and Carbohydrate Deficient Transferrin tests are sent to The Doctor’s Laboratory in London, with whom we work in partnership. We do not offer reports for analyses that have not been performed at our laboratory in Cardiff. When using blood tests, either on their own or along side hair testing, it is recommended to use a clinical assessment from an experiences substance misuse professional.

Research

Do hair tests discriminate between fair haired and dark haired people?
Although studies have shown slight differences in the amounts of drug that are deposited in fair and dark hair, this will not affect the results of our analysis. Due to the fact that the levels of drugs found in dark hair are rarely compared to levels found in fair hair the differences can be considered irrelevant.

What studies have been published on hair testing?
The regular monitoring of drug users by the use of hair analysis started with an article in a medical science journal in 1979. Since then over 400 papers have been published on the use of hair analysis in Forensic Science International, The Lancet, British Journal of Psychiatry, Therapeutic Drug Monitoring, Journal of Analytical Toxicology, International Journal of Legal Medicine, European Journal of Clinical Pharmacology, American Journal of Drug and Alcohol Abuse, International Journal of Drug Testing, Journal of Forensic Science, Clinical Toxicology, Journal of Pharmaceutical Science, New York Academy of Medicine, Folio Pharmacologica, Japonica.

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