Hair Testing

Hair testing is among the most accurate laboratory tests for
drugs and alcohol – and is almost impossible to cheat.

The method can be used to detect virtually all drug and alcohol substances, between 7 days and
6 months after their use. Test results also indicate the month in which a donor ingested a
substance, and can therefore be used to build a ‘picture’ of substance use over time.

‘Fixing’ a hair test is exceptionally difficult. Hair samples cannot be tampered with – even bleaching
has negligible effect on test results – and bald donors can be tested using their body hair.

Today, Cansford Laboratories offer hair test results within 3 days of receipt
– the fastest hair testing service in the UK.

Our team continues to invest in the research and development of hair testing, after our founders John and Lolita pioneered the method 25 years ago.

What you need to know about hair testing:

Detection window:

  • For alcohol, 7 days–6 months
  • For drugs, 7 days–indefinite (dependant on hair length)

Substances tested for include:

  • Amphetamine
  • Methamphetamine
  • Cannabis
  • Cocaine
  • Ketamine
  • Tramadol
  • Opiates
  • Methadone
  • Mephedrone
  • Benzodiazepines.

Contact us for any additional substances you need testing.

    Collection method:

    • A hair sample of around 5-millimetre thickness is taken from the head or body of the donor, and deposited in a sealed, tamper-proof envelope. This is sent to the laboratory for testing.


    • Exceptionally difficult to cheat
    • Indicates patterns of drug or alcohol use over weeks and months
    • Highly sensitive; highly accurate
    • Simple, non-invasive collection
    • Fast results turnaround, when performed by Cansford Laboratories.



    • Hair tests cannot precisely determine the quantity of substances used by the donor
    • Samples cannot indicate substance use less than 7 days after the incident.

    How does hair testing work?

    When ingested, drugs and alcohol produce specific chemical markers in the body called metabolites. These markers pass into hair, which subsequently acts as a record of an individual’s drug or alcohol use. The presence of the metabolites helps to prove that the compound was ingested by the donor, and not simply the result of external contamination – for example, another person using drugs in the donor’s presence.

    Hair typically grows at about one centimetre per month. When tested, each centimetre of hair therefore reflects one month’s history of drug use (or non-use). This is why hair strand testing is able to provide such a large window of detection, assessing drug use as far back as 6 months.

    Essentially, the time frame of detection required dictates the amount of hair required for the sample. If a court orders a hair test to assess drug use in the past 4 months, then 4 cm of hair will be analysed.

    Hair takes around 7 days to grow out of the scalp – which is the minimum time window a hair test can detect. It may therefore be necessary to use hair testing in conjunction with blood and (oral fluid) saliva testing.

    Learn about our other testing services

    Interested in hair testing with Cansford Laboratories? Request a quote below

    Got questions? Read our testing FAQs

    Collecting quotes for drug, alcohol, or DNA Testing?

    Request yours below, or contact our lab team with your questions about testing on
    029 2054 0567