How and why?
Drug testing in the workplace is controversial, but there is a compelling argument in favour of screening when drug use could impact on other people and business activities. Jacqui Cleland-Pottie reports for Safety First.
Side from the health risks of drug use, even casual users feel awful for days afterwards, affecting work performance and increasing the risk of accidents.
While not as common as alcohol consumption, drug use is part of Australian life. The impact of employee drug use can be devastating. In 2003, more than 21% of people aged between 21 to 29 had been abused or put in a state of fear by someone under the influence of illicit drugs. Many of these incidents occurred in the workplace.
Substance abuse policies covering drugs, alcohol and impairing substances such as solvents are increasingly common among Australian businesses as pressure from insurers mounts.
To earn the support of the workforce however, all screening must be done on the basis of health, safety and welfare. An effective policy must be backed by some form of testing.
Oral fluid and urine testing - why two technologies?
Two types of drug tests are used for screening in Australia - oral fluid and urine. Each does a specific job and is not interchangeable.
The major difference is in the timing. After a snort of cocaine, the drug enters the bloodstream and affects the brain within several seconds.
Minutes later, it is in oral fluid and in a matter of hours it appears in the urine. A month or two later, it can still be found in the user?s hair.
A urine test shortly after a cocaine hit would yield a negative, unless use was habitual. Only an oral fluid test could confirm whether a person is currently under the influence.
Conversely, oral fluid tested after a couple of days would be negative even though a urine test would be positive. Pre-employment screening using saliva is useless if the person has abstained from drugs prior to the interview, which is when urine testing is ideal.
Oral fluid tests
Because drugs permeate the body, irrespective of whether they are ingested, snorted or swallowed, any oral fluid (not only pure saliva) can be used for drug testing. Once drugs are in the oral fluid, the drug has also reached the blood and the brain, impairing the person. For this reason, many companies are adopting oral rather than urine testing, especially in ?for cause? cases. As yet though, there are no legal limits for driving under the influence of drugs.
Collection devices are very important because some drugs will bind to unsuitable materials. The best collector is a simple non-binding sponge on a stick.
The main technology for many years, urine tests are generally cheaper than oral fluid tests.
Urine is a good medium for drug detection provided the test is not being carried out to detect impairment, which has mostly ceased by the time the drug is in the urine. The donor may however still be in withdrawal or in a depressed condition, so urine tests could be used ?for cause? to identify those in withdrawal.
The disadvantages of urine testing are the embarrassment associated with urine collection and a proliferation of products on the internet to ?fool a drug test?, although most are ineffective.
Positive test results should be supported by a confirmation test conforming to Australian Standard AS/NZS 4308:2001 using either GC/MS or HPLC/MS. Many of these sensitive analysers measure parts per billion or parts per trillion ? they would have the ability to detect a cup of coffee tipped into a lake.
Always conduct the confirmation test on the same sample because the next urine sample may be different and it is not appropriate to screen with oral fluid then confirm with a urine sample.