Register for Trace Contamination of Androstenedione Causes Positive Steroid Test Results
Sports MedicineDecember 18, 2000
(NewsRx.com & NewsRx.net) -- A metabolite used as a marker to detect use of the banned anabolic steroid nandrolone was found in urine samples of men who took over-the-counter preparations of the sports supplement androstenedione, according to an article in the November 22/29, 2000, issue of The Journal of the American Medical Association.
Don H. Catlin, MD, of the University of California, Los Angeles, and colleagues tested over-the-counter (OTC) androstenedione products to assess content and purity, and to determine if ingestion can cause positive test results for the inactive metabolite 19-norandrosterone. A positive urine test for the presence of 19-norandrosterone is used to detect use of nandrolone, an anabolic steroid banned by sports organizations. Nandrolone itself is rarely found in urine.
According to background information cited in the study, up to $800 million is spent each year on sports supplements. Androstenedione, 19-norandrostenedione, and other androgenic steroids are widely available OTC and via the Internet. Athletes take OTC steroid supplements for their alleged muscle-building properties. Package labels often do not warn that these supplements may contain substances that are banned by sports organizations and may cause a positive urine test result. Recently, there has been an increase in the number of athletes who have tested positive for nandrolone.
The authors studied the effects of OTC androstenedione preparations taken by healthy men. A total of 41 men, aged 20 to 44, took part in the study from October 1998 to April 2000. Thirteen men received 100 milligrams a day, and 11 men received 300 milligrams a day of oral androstenedione, for seven days. Thirteen men took no androstenedione, and four men received 10 micrograms of 19-norandrostenedione.
"We found 19-norandrosterone, a metabolite of the prohibited steroid nandrolone, in all urine samples obtained after oral administration of androstenedione and in none of the urine samples collected before androstenedione administration," the authors wrote. "Urinary concentrations were measured for day 1 vs. day 7 measurements; mean 19-norandrosterone concentrations in the 100-mg/d and 300-mg/d groups were 3.8 ng/mL and 10.2 ng/mL, respectively," Catlin et al. continued.
Though the concentrations were small, 20 men would have tested positive for 19-norandrosterone using the International Olympic Committee cut-off for testing samples from competitive athletes. "The 19-norandrosterone content exceeded the cut-off for reporting positive cases (greater than 2.0 ng/mL) in 20 of 24," the researchers said.
Finding 19-norandrosterone was unexpected, Catlin et al. remarked. This led them to test the androstenedione capsules used in the study for impurities at a sensitivity of 0.001%. Previously the authors had shown that the preparation was pure at a sensitivity of 0.1%, however at 0.001%, 19-norandrostenedione was found in amounts of 4-18 micrograms per capsule. To show that these small amounts of contaminants could produce the positive test result, the authors administered 10 micrograms of 19-norandrostenedione to four subjects.
All urine samples from these subjects contained 19-norandrosterone. The authors report six of the nine brands of OTC androstenedione preparations were found to be mislabeled.
"Of seven brands of androstenedione analyzed at the 1% level, one contained no androstenedione, one contained 10 mg of testosterone, and four more contained 90% or less of the amount stated on the label," they reported.
The authors asserted the 19-norandrosterone found in the study is almost certainly due to ingestion of contaminated androstenedione, although they do not have information to determine how the contamination might have occurred. "Sport organizations that test for anabolic steroids have banned androstenedione even though it is sold OTC in the United States. The data reported herein show that contaminated androstenedione administration will, like nandrolone and 19-norandrostenedione, be detected as 19-norandrosterone in urine and can produce a positive test result for anabolic steroids in subjects taking OTC dietary supplements," Catlin and associates concluded (JAMA, 2000;284:2618-2621).
This work was supported by the following organizations, all in the U.S.: the National Football League, the National Collegiate Athletic Association, the U.S. Olympic Committee, Major League Baseball, the Major League Baseball Players Association, and grants from the National Institutes of Health. The funding organizations did not participate in the design, conduct, interpretation, or analysis of the study.
This article was prepared by Health & Medicine Week editors from staff and other reports.
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