Aug. 2, 2006 — The test to detect synthetic testosterone — used on Tour de France winner Floyd Landis' urine sample — is highly accurate, experts say.
Philippe Verbiest, the lawyer for cycling's world governing body, confirmed Tuesday that a carbon isotope ratio test, which detects a subtle chemical difference between the natural and synthetic versions of testosterone, was done.
The New York Times has reported the test detected the synthetic hormone, but Verbiest refused to give any details of the result.
The test focuses on carbon atoms in testosterone molecules. These atoms come in different types, called isotopes. The ratio of one particular isotope to another isotope is different in synthetic versus natural testosterone. The test detects that difference.
When the lab procedure is performed correctly it is very accurate, said Dr. Don Catlin, the director of the UCLA Olympic doping lab. He helped develop the test.
Dr. Gary Wadler, an internist and author with expertise in the area of drug use by athletes, said he's not aware of anything other than synthetic testosterone that will produce a positive test result.
When athletes take synthetic testosterone to boost performance, it typically helps them get stronger, recover faster from workouts, prevent tissue breakdown and increase their assertiveness, said Wadler, a member of the World Anti-Doping Agency who stressed he was not speaking for that group.
Testosterone can be injected, he said, though athletes are moving toward taking it by skin patch or cream, which allows lower doses that might escape detection. Typically, athletes take the hormone daily for weeks or months during training, Wadler said, because it takes a while for the benefits to appear.