Test Types

Drug Test Specimens: Test Types and Standards

Drug tests are generally conducted using specimens of urine, oral fluids, or hair.

Urine and oral fluid specimens may be tested at the collection site (known as POCT or Point Of Collection Testing) or in a remote laboratory.

Specimen testing may be subject to DOT (Department of Transportation) standards, or State standards, or individual lab standards, or perhaps standards established by the manufacturer, distributor or user of devices or reagents used in the testing process.  Two different testing devices or labs may use a significantly different “limit of dectection” (l.o.d.) and/or different threshold for reporting a result as a “positive”.

Even DOT “standards” do not guarantee that one lab’s tests follow the same procedures as another lab: e.g., SVT (Specimen Validity Testing) is (under DOT regulations) a “voluntary mandatory” standard (i.e., SVT testing is voluntary at the discretion of the lab, but if the lab does SVT testing, it must follow certain standards). A lab may offer SVT for certain types of adulterants, but not other types.

MRO (Medical Review Officer) procedures may follow a similar pattern of standards (e.g., with respect to DOT-regulated testing) or may (in the case of non-DOT regulated drug testing or testing methods) be largely at the discretion of the MRO…or not offered.  In many states, MRO services may not be required (i.e., except for DOT-regulated testing) and may not be provided by the testing service. 

What specimen to use?

Some testing methods are more appropriate for certain testing situations and less appropriate for other circumstances.  For example: a hair test is not relevant for post-accident or reasonable suspicion (R/S) testing in the sense that there is little “nexus” between the test result and the time of the accident or R/S incident.  The reason is that hair has to grow for a few days before it is far enough above the scalp to be within the test sample.  Consequently, drugs that are in the person’s system on the day of an accident or R/S incident will not be in a hair specimen collected on that day…if drugs are present in the specimen, the drug(s) would be from a period of time ending a few days prior to the accident or R/S incident that triggered the drug test.  Urine or oral fluid testing would provide a better “nexus” to the accident or R/S incident. 

On the other hand, because it can detect drug use over a period of 90 days prior to collection of the specimen, hair testing is an excellent choice for pre-employment or random testing; whereas the limited “window of dectection” (w.o.d.) of approximately 24-36 hours for oral fluids makes them largely unsuitable for such tests…unless the employer’s objective is to merely  separate the “really dumb” and “hopelessly addicted” drug users from those who are able/smart enough to stay off drugs for a day or two prior to applying for a job.  Urine testing provides a wider w.o.d. than oral fluids, but substantially less than hair. 

One big advantage of urine testing is the availability of established standards (by DOT) for virtually every part of the process from the implementation of the company’s policy to the reporting of the results and dealing with the consequences of a non-negative result.  In general, it is fair to say that non-DOT regulated urine drug testing following DOT standards avoids some of the potential pitfalls of venturing into less-regulated or un-regulated realms.  When individual states do weigh-in on issues related to drug testing standards, generally speaking, their standards tend to reflect DOT standards.  For more definitive advice regarding state laws affecting drug/alcohol testing, one noted industry source is Wm Judge, atty:  bjudge@lawsinhand.com

However, other technologies have been (and are being) developed to meet specific needs that are perceived to be not adequately addressed by “conventional” (e.g., DOT-regulated) urine testing.  For example, oral fluids testing and sweat testing (“the patch”) have been well received in the law enforcement arena, especially for prison inmates and parolees.  Non-DOT urine and/or oral fluids POCT (Point Of Collection Testing) devices have been used in construction, manufacturing and other industries when clinic-based specimen collection results in too much time away from the job and where “immediate” results are desired…even when those results may not be consistent with lab-based tests conducted to DOT standards.  But big companies can (and do) make those risk-management decisions every day, and may in fact negotiate the standards and consequences with their unions to keep the risks within known (and manageable) limits.

Confused? 
Frankly, I was getting a little confused myself.  So, put together this little “matrix” to make it a little easier to compare the strong points of the specimens, test types and standards.  We still recommend that you get some good guidance…like from one of our Certified Substance Abuse Program Administrators (CSAPA)…
developing your program, procedures, testing methodologies and other aspects of your company’s approach to dealing with the issues of substance abuse in the workplace.