Beating the Drug Test Sample Manipulation, Adulteration and Masking

David L. Black, Ph.D., DABFT, DABCC; Tim Robert, Ph.D., ABB; Peter Stout, Ph.D.

The widespread application of urine drug testing to control or limit the use of illegal and non-medical pharmaceutical drug use has resulted in a variety of strategies by drug abusers to test "negative." Athletes have always been on the leading edge of new techniques to defeat the drug monitoring process, with advice provided by physicians, pharmacologists, medicinal chemists and others with scientific expertise to develop methods that interfere with testing procedures or technology. The various strategies and techniques may be divided into three categories: 1) sample manipulation; 2) chemical interference and 3) masking.

Sample ManipulationSample manipulation involves efforts directed at altering the nature of the sample provided for testing. This category may be divided into simple sample substitution and the use of products to affect the amount of drug and metabolite that is present in the urine sample.

Sample substitution has been a time-honored method of trying to beat the drug test. Drug users have attempted to smuggle “clean” urine into collection facilities using balloons or condoms, bottles and other various devices. Aegis and other laboratories involved in urine sample collection have documented many instances of subjects attempting to transfer their “clean” urine into a urine collection container without detection. Although incidents have occurred where smuggled urine filled balloons/condoms have burst, and thus provided direct evidence of sample manipulation, the current practice is to measure the temperature of the sample immediately after voiding to verify the sample was provided from the body. The Internet does offer products for sale that contain drug-free, freeze-dried urine (just add water!) and heating devices to provide a warm negative sample. Such products have been determined to be faulty, and donors have provided “hot” urine samples (well above body temperature) that are obviously the result of such a product being used. The best response to this effort is to ensure collection staff are trained and certified, and the collection facility follows forensic practices in the urine collection procedure.

Products are marketed through nutrition centers, the Internet, gas stations and convenience stores for the purpose of “diluting” the urine and therefore lowering the drug concentration. The products have been developed and marketed to reduce the drug concentration to below the testing threshold that may be used to identify a sample as positive. One of the oldest such products is Golden Seal Tea or Golden Seal Capsules, that contains natural diuretics that increase the amount of water present in the urine. Today there are many products available for purchase that will increase the water content of a urine sample and reduce the drug concentration to below common drug screening thresholds; the result is a “false negative” report issued by the laboratory. A typical product (pill, capsule, liquid) provides instructions to drink an excessive amount of water (six eight ounce glasses of water) in one hour within two hours of a sample collection. These products contain Vitamin B to restore the color to the dilute urine so it will not obviously appear dilute; and creatine with the intent to increase creatinine concentration since it is the marker used by most laboratories to identify a dilute sample. Although the products were originally sold to affect a Marijuana test result, the dilution effect will apply to any drug use and may result in a false negative laboratory report. Since these products are used by drug users prior to the sample collection, there is a greater challenge in responding to this sample manipulation practice. Drug policies and program practices should require a maximum two-hour limit for notice to the donor to report to a collection facility to provide a sample. A limited amount of water (16 ounces) should be provided to the donor if they need fluid intake to provide a urine sample; donors should not be allowed to use their own drinks since they may actually be using a product designed to cause a negative test. The program may also elect to use lower testing thresholds to compensate for the possibility of the use of these products; the lower test thresholds will also provide a longer window of drug detection in an individual using drugs.

Sample Adulturation
Sample adulteration involves efforts directed at introducing chemicals into a urine sample provided for testing. Drug users have identified a number of different chemicals that may be used to interfere with the testing process. These chemicals also include some drugs that may interfere with the testing technology to cause a “false negative” report.

Drugs that may be used include Salicylate (Aspirin) and Ibuprofen (Advil). High therapeutic doses of Salicylate have been documented to interfere with enzyme immunoassay (EIA) drug screening technology resulting in a false negative test result on a drug-using donor. EIA has been the most widely applied drug screening technology for Marijuana, Cocaine, Opiates (Narcotics), Barbiturates and other drugs commonly included in urine testing profiles. Newer technologies are not as affected by Salicylate use, but screening tests continue to be widely dependent on EIA, resulting in the possibility of false negative test results by this technique of “beating the drug test”. High therapeutic doses of Ibuprofen have been documented to interfere with Gas Chromatography/Mass Spectrometry (GC/MS) confirmation testing for Marijuana. The primary metabolite from Marijuana use is identified as Carboxy-THC (11-nor-9-carboxy-delta-9-tetrahydrocannabinol), which Carboxy-THC (11-nor-9-carboxy-delta-9-tetrahydrocannabinol), which requires a special sample preparation step prior to GC/MS testing. High concentrations of Ibuprofen in the urine may interfere with this special sample preparation step resulting in a false negative GC/MS test result. Certified laboratories are aware of this interference and have modified their GC/MS confirmation methods to minimize the possibility of a false negative test produced by Ibuprofen.

Chemicals used to interfere with the testing process include salt, vinegar, bleach, Visine, nitrites, chromates and strong oxidizing agents to destroy the targeted drugs and metabolites used by laboratories to identify a drug using individual. These chemicals must be added to the sample at the time of sample collection. Small salt packets from fast food restaurants are often smuggled into the collection facility to be added to the urine sample; salt interferes with EIA technology and may result in a false negative test result. Bleach and vinegar are added to a urine sample to change the pH and interfere with the EIA enzyme activity, which will produce a negative test result. Visine is used to isolate drugs and metabolites into little “droplets” in the urine sample, which then minimizes the possibility of the “droplet” being included in portion of urine used for the screening test, resulting in a negative test. Nitrites, chromates and similar oxidizing chemicals actually react in the urine sample to destroy the drugs and metabolites normally included in testing to identify a drug user. To minimize the opportunity for chemicals to be added to the urine sample at the time of collection, a trained and certified collector should perform the collection. A further protection against this strategy of defeating the drug testing process includes analysis for nitrites and chromates in every urine sample. A positive report for nitrites or chromates should be treated the same as a positive urine test for illegal drug use. Currently there are no tests to verify salt or Visine addition to a urine sample; bleach and vinegar adulteration of a sample may be verified indirectly through pH measurement of the urine sample. Newer technologies are not as affected by salt, vinegar, bleach or Visine; all test technologies are affected by nitrites, chromates and oxidizing chemicals.

Masking Masking involves efforts directed at either rapidly removing drugs from the body prior to an announced drug test, or blocking the removal of a drug from the body through the kidney and urine. The intent is to use one drug or chemical to greatly reduce the urine concentration of an illegal drug. Such efforts involve using drugs and chemicals to alter the pH of blood and/or urine and interfering with the elimination of drugs and metabolites from the body through the kidney. Drug users may consume/drink dilute bleach and vinegar in an effort to change blood and urine pH to more rapidly remove drug from the body, or to “hold” the drug and metabolites in the body. Some drugs, such as Amphetamines, may be significantly affected by blood and/or urine pH, and other drugs are much less affected by this strategy. Anabolic steroid users have used Probenecid (Benemid) and Carbamates to block the elimination of steroid metabolites from the body through the kidney and urine. An effective response to the use of masking agents is for the laboratory to include the drugs in the screening process.

Other Issues Although the drug using population has focused on techniques to defeat urine drug testing, there are various strategies and products available to affect hair and saliva testing. Internet products are sold to “wash” drugs out of the hair prior to sample collection, or to use strong oxidizing agents (dyes) to destroy the drugs and metabolites. Products are also available (Saliva Cleanse at www.ipassedmydrugtest.com) that are designed to beat a saliva drug test.

Defending Your Program
In many programs, the responsibility of conducting the urine collections falls to the athletic trainer. If this applies to you, then there are steps you can take to defend your program against these attempts to “beat the test.”

  1. Limit the amount of time between student/athlete notification of the collection and the collection event to less than two hours. While it is sometimes difficult to monitor and enforce strict time limits, a short the time period between notification and collection limits the opportunity for the methods described in this article to be used.
  2. Control access to liquids consumed at the time of collection to ensure that adulterant products (many of which are made to look like sports drinks) are not being ingested during the collection event.
  3. If you are not using a “direct observation” procedure in your collections then be sure to place bluing agent in toilets and tape off the faucets so water cannot be used to dilute a sample. Also subjects should be required to wash their hands prior to the sample collection to protect against chemicals being present under fingernails or dried on the skin.

Many laboratories (including Aegis) offer Forensic Urine Collection training programs and it is recommended that all staff conducting collections be trained to insure a secure and confidential process.

David Black is the president and laboratory director for Aegis Sciences Corporation, a sponsor of CATS. Questions or comments can be sent to drblack@aegislabs.com. Co-authors Tim Robert can be reached at trobert@aegislabs.com. and Peter Stout, pstout@aegislabs.com.


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