Pubdate: Thu, 10 Jul 2003 Source: Manila Bulletin (The Philippines) Contact: http://www.mb.com.ph/ Details: http://www.mapinc.org/media/906 Bookmarks: http://www.mapinc.org/area/Philippines (Philippines) http://www.mapinc.org/testing.htm (Drug Testing) US EXPERT EXPLAINS DRUG TEST COMPLEXITIES RICHARD E. Struempler is president and chief executive officer of Total Quality Management Services, Inc., a Texas-based consultancy firm on drug tests that maintains an office in Manila. Struempler has over 25 years of experience in Forensic Urine Drug Testing, and over 14 years under his belt managing SAMHSA-certified drug-testing laboratories assaying over 30,000 specimens per month. He has also established programs for education and training in Forensic Urine Drug Testing for all levels. Here he fields questions, via e-mail, from the Bulletin on the complexities of the urine drug-testing procedure - questions that may be playing on a lot of people's minds ever since the drug controversy erupted in the Philippine Basketball Association. MB: What does a 'positive' result really mean? Struempler: A "positive" result simple means that a drug or drug breakdown product was detected in the urine at or above a pre-determined "cutoff" level. One unit below the cutoff level and it would have been reported as "negative". A positive result CANNOT tell you when or how much drug was used, nor can it tell you if the use was a one-time experiment or a chronic drug abuse problem. If appropriate cutoff levels are used in the case of marijuana use, you can say that the positive result DID NOT come from breathing second-hand smoke. This is the most common reason given for a positive marijuana result by the donor. MB: When does 'positive' result not indicate drug abuse/ drug use? S: A "positive" drug test indicates only that the drug(s) being tested were present in the urine. It cannot tell you how the drugs came to be present. Before determining a finding of "drug abuse" from the donor, someone with knowledge of drug testing issues must be able to rule out the presence of drugs not related to abuse. For example, morphine may be present in the urine due to prescription medication with codeine in it, eating certain types of poppy seed cakes or muffins, or from the use of heroin. Only the latter would typically be consistent with drug abuse. The other two causes would be considered a medical exception, and the result should be reported to the person receiving the final result as a "NEGATIVE" even though morphine was detected. MB: What do 're-test' results achieve? S: "Re-tests" can come in a number of forms -- from a re-testing of the original "positive" sample, to a recollection and then testing of that second sample. If the original sample is retested, then the method used for the re-test must be either the same or technically superior to the original test. Due to breakdown of the drug over time in the urine, a re-tested sample could easily reveal lower amounts than originally detected, and this may be interpreted in error and considered now "negative". A second sample collected and then tested as "negative" should never be allowed to impeach a previous "positive" sample. The second sample could easily have been collected outside of the "window of detection", or that time period in which drug can be detected, from the last use. MB: Most of the cases the PBA is handling involves metampethamine hydrocloride, otherwise known as 'shabu.' Is it possible that this substance can manifest itself in a urine drug test through the use of over-the-counter medication, diet pills or food supplements? S: Depending upon the testing procedures used, some cough and cold medicine as well as diet pills can result in a "false positive" test for "shabu". This is the problem with many of the "screening" or immunoassay tests. The active ingredient in many cold and diet preparations is very similar to methamphetamine or "shabu" or as we call it, "crystal meth". Any positive result must be confirmed by a second more specific test to rule out the false positive that may occur. This is a critical aspect of testing for "shabu". MB: In your almost 30 years in this field, have you ever encountered a case where a drug test made a mistake? S: In 1982, the US Navy drug-testing program reported out literally several thousand positive drug testing results that did not meet appropriate scientific evidence. These had to be reversed, or officially reported as "negative". Most of these, we believe, were in fact true positives, but not all of the steps necessary for a valid result were present. Rather that risk falsely accusing someone of drug use, all of these results were thrown out. It was this event that lead to the development of the rigid drug-testing program now used in the United States. These events were very similar to what I see occurring with the PBA at this time. It appears to be the same issues on a smaller scale. Since the revision of the program in 1983, and literally millions of tests performed, I have personally seen only two specimens where a laboratory that was following US guidelines for testing was not able to reconfirm a previously reported positive result. MB: If there are mistakes, where do they usually occur? S: In these cases, we were not able to determine an analytical error or mishandling of the specimen. These 1-in-10,000,000 or more "false-positives" remain a mystery today. In general, most errors occur at the collection site -- not in the laboratory. MB: In the US, what are the chances of a 'human error' marring the tests? S: This is a very interesting question that is almost always raised by attorneys representing a person with a positive test. In the US, the entire program's quality control and risk management is designed to err in favor of a negative result. If in the processing of the sample, there is ever a question regarding the proper handling or testing of the specimen, a "negative" result will be reported. Only results in which there is clear indisputable evidence by scientific methods is a "positive" result reported. As a result, there are those who use drugs who will not be detected. The idea is that if you randomly continue to test employees, those who use drugs will continue to use drugs and will eventually be detected. The program must be designed to have NO FALSE POSITIVES. Those being tested must also be given the opportunity to provide evidence of a legitimate medical explanation for positive results, such as prescription medication, and those results would also be reported to the "employer" as a NEGATIVE meaning "negative for abusing drugs". As I have indicated, this field of science is very complex, with new issues coming up each day. That is why it is critical that those administering the program understand and deal appropriately with these issues. S: As you can tell from these responses, issues involving urine drug testing, can be somewhat complex. To those not familiar with the science of urine drug testing or attempting to manipulate information, it is easy to create a smokescreen of excuses for a positive test result that could cause others to doubt the validity of the result. Urine drug testing can be a valuable tool in fighting the war against drug abuse, but if specimens are not properly collected, handled, tested and results interpreted correctly, then urine drug testing can be a disaster for both those being tested as well as those trying to administer their program. - --- MAP posted-by: Richard Lake