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Your Drug and Alcohol test results

Interpreting Drug and Alcohol Test Results

Cellmark provides rapid and reliable hair testing for drugs and alcohol abuse, providing scientific analysis that is clearly reported and simply explained. We are one of the UK’s largest suppliers of forensic analysis to the police and the UK’s most experienced DNA paternity tester. Our ISO 17025 accredited labs have 35 years’ experience of delivering market leading scientific testing to the public, the legal community and the courts.

When would you use hair drug and alcohol testing?

Hair strand samples (not the hair follicle) can provide a unique history of an individual's drug and excessive alcohol use.  Using forensic toxicology, we analyse samples such as hair for the chemical traces that reveal this history. Hair toxicology can therefore be an essential part of family court proceedings, especially when a child's safety is in question.

Our hair testing service can provide evidence of drug or alcohol abuse over time. Segmenting the hair strand into monthly sections enables us to identify patterns and trends. It can also help provide supporting evidence for parents claiming to have stopped taking drugs, even if they have used drugs in the past. At Cellmark we understand the importance of providing clear and concise results, allowing our customers to make vital decisions in care proceedings.

How are the hair drug and alcohol results reported?

Once hair samples have been collected under chain of custody conditions by an experienced sampler, testing can be carried out at the laboratory. Cellmark’s toxicologists will then summarise the results into an easy-to-interpret document suitable for judicial use.

We always recommend that our customers opt for the Witness Statement report as this provides the most comprehensive interpretation of the findings, including disclosures provided at the time of sample collection (e.g. any hair treatments or prescribed medications) together with the professional expert opinion of the Reporting Scientist. This includes donor identification information, the date of the collection and the results of the test.

Are there any limitations?

Hair testing is the only scientific way to track a person’s long-term history of drug or alcohol usage in a single sample, but there are some things it cannot reveal. It cannot, for example, tell you the exact day and time that any drugs or alcohol were consumed. It also will not reveal drugs taken in the last few days and it may not detect very occasional or low-level use. Hair treatments like bleaching, perming, dyeing and straightening may have some impact on the results of a hair drug test. We therefore always ask for information about hair treatments when samples are taken, which allows our toxicologists to take anything relevant into account when analysing the results.

Our friendly and knowledgeable customer service team are here to guide you through every step of the process. For help with your testing requirements please give us a call on 0800 036 2522 or email us at