Clinical Textbook of Addictive Disorders 3rd ed - R. Frances, S. Miller, A. Mack (Guilford, 2005) WW

4. Laboratory Testing 67tive in laboratory A may be reported as negative by laboratory B, based on differentcutoff levels. This is not a new development (Hansen, Caudill, & Boone,1985). Unfortunately, little progress has been made in correcting it over thepast 17 years. The issue is not the type of test administered, or poor-quality laboratories,but rather the nonstandardized threshold for reporting a test as positive.Evasion of True Positive ResultsFor obvious reasons, drug users are highly motivated to “produce” a clean sample.In response to this need, a black market has emerged to provide products with thesole purpose of creating a false-negative test result. These products include pretestedand certified drug-free urine substitution kits, and a variety of adulterants.These include the “Whizzinator” (an artificial penis used to deliver a known drugfreeurine under direct observation conditions) and passingpisstest.com, whichprovides a nontechnical description of how blood and urine drug tests work.Those who interpret test results should be aware that addicts can be highlycreative in their efforts to thwart detection and monitoring. As an example,adulterants are substances placed in a sample to alter the results of a drug test.They accomplish this by physically altering the characteristics of the sample, suchas temperature, pH, and specific gravity, which disrupts the mechanisms of theassay. Adulterants range from inexpensive household products, such as soap, salt,bleach, lemon juice, or vinegar, to expensive additives specifically marketed toproduce a negative test. One Internet product selling for over $100 comes with a300% money-back guarantee. As a result of adulterant use, drug testers must nowemploy techniques to screen for these additives. If the sample does not fall withinestablished physiological parameters at the time of collection, it is voided on thespot, and another sample must be produced, which is then sent to the laboratoryfor analysis. One “do-it-yourself” kit, available on the Internet, includes a concealedIV bag with tubing (to be strapped to the lower abdomen or upper thigh)and two heating elements with temperature strips, all in an attempt to mask theuse of adulterants. One study demonstrated the ability of one adulterant to createfalse negative tests (Cody & Valtier, 2001).MECHANICS OF DRUG TESTING PROGRAMSChain of Custody and the Medical Review OfficerA critical component of all drug testing protocols (sports and workplace) ischain of custody, which refers to the policy whereby the collected sample (usuallyurine) never leaves the direct observation of a member of the drug testingteam until it arrives at the laboratory. Once collected, the processed sampleremains under the direct observation of the testing team until it is hand-