Chapter 11

Drug Testing and Adulteration

THE DRUG TESTING PROCESS

When a specimen is received at the laboratory it goes through the following process.

1. Accessioning Department.
   This is the area of the laboratory responsible for bringing the specimen into the laboratory environment, logging its arrival and determining if procedures, including chain-of-custody, were followed, if seals are intact, etc. Accessioning then takes the donor information and enters it into the laboratory computer database. The bar code that appears on both the collection form and the sealed bottles is scanned into the computer, identifying the donor information in the database and specimens with the bar code number. Accessioning then releases the specimen labeled "A" and copy 1 of the collection form to the laboratory for testing. Accessioning sends copy 2 of the collection form to the medical review officer and copy 3 along with the specimen labeled "B split" to freezer storage until results of the drug screen are available.
   
   
2. Laboratory drug screen.
   When the laboratory receives the specimen for screening, the bar code is scanned from the bottle and a printer reproduces a label that is placed on a test tube. A lab technician then compares the two bar codes both visually and electronically and proceeds to transfer a small amount of urine from the bottle labeled "A" into the bar-coded test tube. The test tube is transferred to a large carousel containing other specimens and a screening test is quickly performed on all specimens. If a specimen should test positive for one or more drugs, the specimen is flagged in the computer database for confirmation testing, a duplicate bar code seal is printed and placed on the specimen, and it is sent to the confirmation department. If the results are negative, the results are quickly logged into the database and results are electronically transmitted via secured means to the medical review officer for reporting.
   
   NOTE: Quality assurance is maintained at laboratories by means of organizations such as CAP, CLIA and SAMHSA. These organizations monitor laboratory results and send out random proficiency tests to the laboratories to determine if they are maintaining their accuracy. In addition to these proficiency tests, every carousel or run of tests includes three blind proficiency tests that only the Accessioning Department knows about. The three blind specimens contain one negative, one positive and one cutoff, all of which are indistinguishable to the laboratory personnel. Also, collectors for DOT-regulated employees must submit double blind proficiency test specimens to laboratories. These are the same type of specimens, but are submitted after every 100 tests without the knowledge of even the Accessioning Department of the laboratory.
   
   
3. Laboratory confirmation testing.
   When a positive specimen is received for confirmation testing, the bar code on the bottle is scanned into the printer, which duplicates a bar code for each positive drug requiring a confirmation test. These labels are placed on test tubes and specimen is transferred from the bottle to the test tubes and placed into the GC/MS (Gas Chromatography/Mass Spectrometry) unit. The GC/MS not only determines the amount of a type of drug in the specimen; it also identifies it using a large database library of drugs. Once confirmed, either positive or negative, the results are electronically transferred to the medical review officer for reporting.
   
   
4. Laboratory freezer.
   If a specimen is negative, the laboratory will dispose of the bottle labeled "B split" within a few days. If the specimen is positive, then the split specimen stays in storage, until the medical review officer calls and asks to have the specimen sent to another laboratory, or until 90 days have elapsed. After 90 days the specimens are destroyed.