Testing
Drug testing is carried out in a two-step procedure:
  
Immunoassay
Screening:

GC-MS
Confirmation:
Detecting the presence of a 
given drug (class)

Specifying the identity and quantity of a particular drug

If the qualitative screening test is negative the donor is cleared. If not, a second confirmatory test must be carried out by a certified laboratory, testing another portion of the primary sample, using a different methodology: gas chromatography - mass spectrometry (GC-MS).

Similarly the police performs an initial (random) breath alcohol test and a blood test for confirmation - or performs a confirmatory test with an evidential breath test (EBT) device that prints out readings and calibration status etc. Normally, when doing road side testing, the police are not interested in testing of urine specimens as they will not provide any evidence of impairment - or driving under the influence (DUI).

As a golden rule, screening and confirmation testing should be performed by using the same specimen - or specimens with similar "Window of Detection" (i.e. blood/breath/oral fluid/saliva).

Workplace drug testing has long been based on urine testing, which can be performed:

On-site:
Laboratory:
Screening
Screening + Confirmation
  
Some of the best performing on-site test devices (AccuSign™) perform at lab-equivalent accuracy (95-99%). Only GC-MS confirmation testing is 100% accurate. There are a number of producer sponsored studies available (comparing the accuracy of various on-site tests) and a few independent.

When it comes to oral based drug testing, there are still no FDA cleared on-site test devices - instrumented or non-instrumented - available for the six Australian workplace drugs. The reason being that the drug concentrations found in oral fluid (and saliva) are so much smaller (1/10-1/100) than in urine and thus difficult to detect without laboratory equipment. The ROSITA study also covers the present oral based on-site tests being offered.

At this stage there is only one FDA cleared oral based drug test that meets the present oral fluid screening and confirmation cut-off levels, and that is the new laboratory based test: Intercept™.

For a complete comparison of a traditional laboratory based urine drug test and the new oral fluid drug test, see: Comparison.
 

 

 

Substance abuse in the workplace and the law

Let us assist you in meeting your various legal obligations in the workplace, by introdu-cing a fair and equitable D&A program - based on four components:

  • Policy
  • Awareness
  • Testing
  • Assistance

The program is the result of a joint effort between Deloitte Legal, policy making, and Drug Testing Africa, testing equipment and services.

 

 
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DTA