Not All Testing Kits Are The Same
In every industry, choosing the right tools for the job and using them in the right manner, is the best way to ensure quality, efficiency and delivering the best results. It is no different when it comes to drug testing in the workplace, or any other environment.
How do you know which kit to choose?
When choosing which kits to use for your workplace drug testing program, or other drug testing program, the choice should not simply be on price. You should consider accuracy, sensitivity and specificity. You should also consider how relevant the panel of drugs is to the country in which you are testing, the persons you are testing and whether the kits are made using the appropriate cut-off levels for that country/application.
Different cut-off levels
Many countries have different cut-off levels/guidelines. As an example, there is currently several differences between the UK (EWDTS – European Workplace Drug Testing Society) cut-off levels and USA cut-off levels for drug screening. Many “cheap” drug testing kits available in the UK are manufactured with the USA cut-off levels.
Using a USA generic cut-off drug test kit for UK workplace drug testing is likely to provide you with inadequate/incorrect test results compared to using drug testing kits with the lower cut-offs recommended for drug testing in the UK, using the EWDTS guidelines.
In practice this is very possible because drug testing kits based on USA (SAMHSA/DOT) Standards have many higher cut-off levels than the UK (EWDTS) for most drug classes, see the table below.
Cut-off levels
| Drug Class / Metabolites | UK/EWDTS Screening Cut-Off Guideline [Urine] | Generic (often USA) Point Of Care Screening Cut-Off [Urine] |
| Amphetamines (AMP) | 500 ng/mL | 1000 ng/mL |
| Benzodiazepines (BZO) | 200 ng/ml | 300 ng/ml |
| Buprenorphine (BUP) | 5 ng/ml | 10 ng/ml |
| Barbiturates (BAR) | 200 ng/ml | 300 ng/mL |
| Cocaine (COC) | 150 ng/mL | 300 ng/mL |
| Ecstasy (MDMA) | 500 ng/ml | 1000 ng/mL |
| Ketamine (KET) | 1000 ng/ml* | 1000 ng/mL |
| Marijuana / Cannabis (THC) | 50 ng/mL | 50 ng/mL |
| Methamphetamines (MET) | 500 ng/mL | 1000 ng/mL |
| Methadone (MTD) | 300 ng/ml | 300 ng/ml |
| Opiates (OPI) | 300 ng/mL | 2000 ng/mL |
| Phencyclidine (PCP) | 25 ng/ml | 25 ng/mL |
| Propoxyphene (PPX) | 300 ng/ml | 300 ng/ml |
Why is this important & How could it go horribly wrong?
If a person had consumed cocaine and presented a urine sample containing 295 ng/mL of this drug or its metabolite, it would be considered “negative” using a generic American/USA specific cut-off level test kit. In contrast the same sample would show as a “positive” result using a more relevant drug test kit that has been manufactured to the UK (EWDTS) cut-off levels. The same is applicable across several drugs/metabolites, with some USA cut-off levels being over 100% more than that of the UK (EWDTS) cut-off levels.
This means that a drug testing kit manufactured to the USA cut-off levels may indicate a NEGATIVE result. You then allow the person to go back to work, for example, putting their lives and the lives of others at risk. However, if they were tested using a kit manufactured specifically for the UK market with EWDTS cut-off levels, the result may be POSITIVE and appropriate action taken to manage the risk.
Would you be happy with some Police forces testing for alcohol using equipment that only showed a positive result at TWICE the UK drink/drive level and therefore missing all drivers with a breath alcohol level below that higher level? Whereas other Police forces use equipment that show a positive result at anything above the UK drink/drive level?
No! Then why do the same with a drug testing kit?
Choose relevant drug classes
There are also some drug classes which are tested for in the USA and overseas which may not really be as relevant currently in the UK. A good example of this would be Oxycodone (OXY), which is heavily prescribed and used/abused in the USA. The use of Tramadol (TML) in the UK is far more relevant.
In Summary
Despite what you may have been told or heard, not all drug testing kits are the same. They are not all made using the same strips from the same manufacturer. FACT!
Drug testing kits, urine or oral fluid, can vary hugely in quality, accuracy, sensitivity, specificity, relevance and cut-off levels. Therefore, they can also vary on price. Not all drug testing kits work well, and some may not work at all. A cheap kit that gives negative results all the time, due to it not being fit for purpose, will rarely be challenged by the sample donor. What employee is going to complain about a negative result during workplace drug testing?
Many UK companies and organisations use drug testing kits that are essentially not fit for purpose, i.e. using drug testing kits in the UK which do not follow the European Workplace Drug Testing Society cut-off guidelines.
- Have they been “mis-sold” or “mis-told”?
- Are you just choosing the cheapest option without knowing all the facts?
- Could this be putting lives at risk due to a lack of knowledge/education?
Getting independent advice and choosing the most relevant drug testing kit is imperative to reducing risks and getting it right and legally defensible.
Take a look at the kits you are using, are they relevant for the application and fit for purpose?
If you are not sure how to check, then contact us and I will point you in the right direction. Cost is certainly a factor, however, so is getting the right tools for the job and using them in the right manner. Trying to save a few pennies by just choosing via the lowest price denominator, is likely to cost you far more in the long run. Get it wrong and in the extreme, it may even cost a life.