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Cannabis

A Comprehensive Guide to Cannabis Drug Testing

Introduction to Cannabis

Cannabis is a Class B drug under the Misuse of Drugs Act 1971.

Cannabis testing plays a crucial role in legal cases, including family law, workplace disputes, criminal investigations, and immigration matters. The type of test used—hair, nail, blood, or urine—depends on the legal context and the required detection window. Hair and nail testing are commonly used in family court and child custody cases to assess long-term drug use, while urine and blood tests are preferred in criminal and employment-related cases to determine recent consumption. Accurate and accredited testing is essential to provide reliable evidence in court, ensuring fair legal proceedings and informed decision-making.

Cannabis Street Names

Cannabis has many names. Some popular ones include:

Weed
Pot
Grass
Mary Jane
Ganja
Skunk (high-potency)
Hash (the resin form of cannabis)

On the street, cannabis will rarely be called cannabis.

Cannabis 's Chemical Structure

The active psychoactive compound is tetrahydrocannabinol, Δ9-THC, or just THC. It interacts with CB1 receptors in the brain to produce psychoactive effects. CBD doesn't work that way, but has therapeutic benefits without a high. These cannabinoids create the diverse effects cannabis is known for - euphoria, relaxation, anxiety and depression.

Cannabis drug testing is essential. At AttoLife, we're committed to providing accurate, trustworthy cannabis testing tailored to your needs. Contact us today to learn more.

How To Test For Cannabis

Multiple testing methods are available for cannabis - it's one of the most widely tested drugs.

Hair

Long Detection Window (Months)

Some court-ordered cannabis drug test requests will ask for a hair sample. A hair drug test is one of the most effective testing methods, with a detection window of several months. The cannabis metabolites bind to the keratin fibres in the hair around two weeks after consumption. From there, every 1 cm of hair represents one month of cannabis misuse. Generally, it’s detected for 3, 6 or even 12 months after ingestion. Therefore, realistically, legal, healthcare and workplace professionals can assume cannabis misuse based on the centimetre of hair it's detected in 5cm = 5 months of ongoing misuse.

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Fingernail

Long Detection Window (Months)

Cannabis nail drug tests work similar to a hair drug test. They’re extremely effective at detecting recent and ongoing cannabis misuse. The test can detect up to 12 months worth of cannabis misuse.

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Urine

Medium Detection Window (Days)

Urine tests are one of the most common testing methods for cannabis detection. THC metabolites can stay detectable for varying periods: Occasional users: Up to 3 days Moderate users: Up to 7 days Frequent users: Up to 15 days Chronic users: 30 days or more Unlike blood tests, urine tests don't measure active THC. The focus is on its byproducts.

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Blood

Short Detection Window (Hours to Days)

Blood tests are excellent for detecting recent cannabis use. THC enters the bloodstream quickly after consumption, making this test ideal for roadside traffic offences or workplace incidents. The only drawback is the detection window is short—about 24 hours for occasional users. There are some reports that the detection window is up to 7 days for frequent/ chronic users, but we don't think this information is accurate or reliable.

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Saliva

Short Detection Window (Hours to Days)

Saliva tests are gaining popularity for their convenience, especially for roadside traffic offences. The detection window is usually 24 to 72 hours. The only issue is the test then must be backed up by a blood test to show the active THC levels in the body, which then determines if an offence was committed. The threshold is 2µg/L of blood, and considering the detection window is only up to 24 hours for cannabis blood tests, the offender might be below the level by the time the required confirmation blood test is taken.

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Legitimate Use Cases for Cannabis

Cannabis is illegal in the UK. But, since the law changed in 2018, medical cannabis can be prescribed to treat chronic pain, anxiety, depression, and a range of other conditions where cannabis is deemed a suitable treatment.

Sub-variants of cannabis that don't contain the psychoactive delta- 9-tetrahydrocannabinol, or THC, as it's known, are also commonly sold in the market . For example, CBD oil. CBD products that consumer CBD products are legal if they contain very low amounts of THCin them. Products that contain a significant amount of THC in them are considered illegal. If the used CBD contains considerable levels of much THC (such as more than 1mg per container (such as vape cartridge), this could cause to fail a drug test

Still, a prescription for medical cannabis doesn't warrant misuse. And anything recreational and non-medical isn't a legitimate use case for cannabis. A cannabis drug test addresses concerns where safety or legality is essential.

Will Cannabis Show Up on a Drug Test?

Yes, cannabis will show on drug tests. A THCdrug can be tested by itself and also the test is included on all 5, 6, and 9-panel drug tests as standard (including MOCCA and MOCCAB). Tests target THC and its metabolites, especially THC-COOH. These metabolites linger in fat cells and are released gradually. This metabolite helps to determine usage of cannabinoids.

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How Long Does Cannabis Stay in Your System?

Cannabis detection varies massively depending on multiple factors such as the frequency of use and BMI. Some of the most common detection factors include:

Blood Test: 24 hours for occasional users. Up to 7 days for regular users
Urine Test: 3-30 days or more depending on frequency of use.
Saliva Test: 24 to 72 hours
Hair Test: Several months. Depends on the length of the hair, but typically 3, 6 or 12 months.
Fingernail Test: up to 12 months

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Factors Influencing Cannabis Presence in Your Body

Several variables determine how long cannabis stays detectable:

The amount consumed: Higher doses take longer to clear.
Hydration levels: Drinking water may help metabolize THC.
Activity levels: Exercise can release fat-stored THC.
Health status: Age, weight, and overall wellness play roles.
Purity: purity and amount of THC contained in the used product

Cannabis Use in Legal Scenarios

Drug tests are often essential in legal cases. Some common examples include:

Family law cases: negligence and impairments
Workplace misconduct: Legal cases related to healthcare professionals, etc, not necessarily an office worker.
Child custody disputes: Positive tests may raise concerns about parenting capabilities and child welfare.
Road Traffic Incidents and DUI charges

False Positives and Interpretation of Cannabis Results

While rare, false positives do occur, especially in roadside saliva tests which have about a 10% false positive rate. Common causes include:

Cross-reactivity with medications like ibuprofen
Mishandled samples or outdated tests

Confirmatory methods, like mass spectrometry (MS), help eliminate errors and provide accurate results.

Popular Culture and Cannabis

Popular culture massively influences cannabis misuse. From the iconic Bob Marley to modern rappers that frequently mention cannabis consumption and illegal production and distribution on the streets, cannabis and popular culture are two peas in a pod.

And it's not only music, popular films like Pineapple Express and How High glamorised cannabis misuse.

Notice how they rarely touch on the legal, health, or professional consequences. It's a reminder to approach the subject with balance.

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Notable Forensic Cases Involving Cannabis

Cannabis often comes up in legal investigations involving forensics. Forensic testing and the multiple drug testing methods available for cannabis will show if the drug was present at the time of an offence.

Recent high-profile legal cases in the UK include:

Police seized £130 million worth of cannabis plants and arrested more than 1000 people in 2023.

Three men were jailed after hiding millions of pounds worth of cannabis in Mattresses in October 2024.

Risk of Contamination

It's unlikely that any street cannabis is 100% pure. One study found by the Manchester Metropolitan University and Curaleaf Clinic took 60 samples of cannabis from the streets of the UK and found 90% of it to be contaminated with at least one harmful substance.

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