Published by AttoSure – Workplace & Healthcare Drug Testing
Cocaine misuse is climbing in the UK, with a 2023 ONS report showing a 12% rise in cocaine-related deaths year-on-year and increasing detection in wastewater samples across major cities. As cocaine becomes more available—and more socially accepted in some circles—it’s no surprise that its presence is increasingly felt in the workplace.
This blog is designed for employers, occupational health teams, and clinical managers working in transport, healthcare, logistics, and safety-critical sectors. We’ll cover the real questions:
· If someone takes cocaine on a Friday, will they test positive on Monday?
· What should you do if an employee has a non-negative result?
· How long does cocaine stay in urine or oral fluid?
Why Test for Cocaine in the Workplace?
Cocaine is a Class A drug with no accepted recreational use (unlike drugs such as THC, tramadol, or codeine, which have legal medical applications in some contexts). Its effects include:
· Reduced concentration
· Increased risk-taking
· Impaired decision-making
· Cardiovascular strain and aggression
In high-risk industries, this can have catastrophic consequences.
Will Cocaine Show Up on a Drug Test?
Yes—and it usually shows up as COC on test devices. However, most tests aren’t detecting just cocaine itself, but benzoylecgonine (BZE), a metabolite produced when the body breaks cocaine down. BZE stays in the system longer, making it easier to detect even days after use.
At AttoSure, our Oral Cube, Oral Barrel, Urine Dip Cards, and Urine Cups all include COC testing as standard. COC-positive results should be treated as a non-negative until confirmed in the lab.
How Long Does Cocaine Stay in the System?
Test Type |
Detection Window |
| Saliva | 1–3 days (via Oral Cube or Barrel) |
| Urine | 2–5 days (via Dip Card or Cup) |
| Hair/Nails | Up to 90–120 days — not typical for workplace testing, but used in family court settings via AttoLife |
Example scenario:
If an employee takes cocaine on Friday evening, it is very possible they will still test positive on Monday morning via both urine and oral fluid testing—especially if they’re a moderate or regular user.
Detection is influenced by:
· Frequency of use (chronic users retain BZE longer)
· Quantity and purity
· Individual metabolism and hydration
· Combined alcohol use (produces cocaethylene)
Can Passive Exposure Cause a Positive?
In theory, being in a room where cocaine is used (e.g. smoking crack) could cause trace exposure. However, modern urine and saliva tests are calibrated to avoid false positives from passive contact.
In practice: You would need to inhale or ingest significant amounts of cocaine for it to be detectable in bodily fluids. Simply touching or being near the drug isn’t likely to result in a non-negative test.
What Can Cause a False Positive for Cocaine?
False positives are rare, but can occur. Potential causes include:
· Local anaesthetics like lidocaine or novocaine
· Certain antibiotics and antidepressants
· Sample mishandling or surface contamination
That’s why lab confirmation using GC-MS or LC-MS/MS is the gold standard after any non-negative.
What Should Employers Do If a Test Is Non-Negative?
When a rapid test returns a non-negative COC result, you must act professionally and proportionally. Here’s what we recommend:
1. Pause their safety-critical duties in line with your company policy
2. Document everything – including time of test, chain-of-custody, and any statements
3. Send the sample for confirmation testing at a certified laboratory
4. Maintain confidentiality while the case is under review
5. Avoid disciplinary action until the lab result is returned and assessed
AttoSure does not provide HR policy services—but we do advise that every employer have a clear drug and alcohol testing procedure in place before testing begins.
Why AttoSure?
We support safety-critical industries with fast, reliable, and accredited drug testing solutions, including:
- Oral Cube (saliva-based, 6–16 panel options)
- Oral Barrel (multi-drug POCT with simple results)
- Urine Cup (all-in-one test-and-seal kits)
- Urine Dip Cards (cost-effective screening options)
All are designed for quick administration, tamper-evidence, and UKAS-aligned results.
Final Thoughts
Drug use doesn’t stop at the weekend—and neither should your approach to workplace safety. Cocaine can remain detectable well after the high has worn off, and non-negatives must be handled with care and consistency.
Whether you're implementing routine, random, or post-incident testing, AttoSure is here to help. From rapid testing kits to full lab confirmations, we support safe decisions, confident policies, and legally sound outcomes.
Contact us today to upgrade your workplace testing programme.
Reference
1. Office for National Statistics (ONS), “Deaths related to drug poisoning in England and Wales,” 2023 report.
Available at: https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/datasets