Experts Say Case Against Landis Is Tough to Beat

After spending several days in New York, Floyd Landis has returned home to Southern California, where he will await his fate as Tour de France champion. But antidoping officials working on his case already have evidence that some experts say is convincing enough to show that Landis cheated to win the Tour, regardless of further testing or appeals.

Landis, 30, provided a urine sample after winning Stage 17 in the Alps with a long solo attack. That day, he climbed back into contention for the victory after a miserable performance a day earlier.

The results of two types of tests have thrown Landis’s status into doubt. One of them, a sophisticated measure called a carbon isotope ratio test, will be difficult, if not impossible, for Landis to refute. The test examines the atomic makeup of testosterone in the urine and can determine if it is natural or synthetic.

Landis failed that test, according to a person inside the International Cycling Union with knowledge of the results. Landis’s personal doctor, Brent Kay, confirmed the finding.

The cycling union said it expected the results of a test on Landis’s backup urine sample by Saturday morning, Paris time. If that test comes back positive, Landis would be stripped of his Tour title and would probably be suspended from cycling for two years. If the test comes back negative, the case would be dropped.

A screening on the backup sample will also aim to confirm the ratio of testosterone to epitestosterone in the urine, which is the other type of test used in the case. The initial testing found a level of 11 to 1, well above the World Anti-Doping Agency’s limit of 4 to 1.

Several experts said the carbon isotope test ultimately mattered more than the T/E test because it shows that some of the testosterone found in the sample came from an outside source, not from a natural process in Landis’s body.

“It’s powerful evidence that’s pretty definitive,” said David Cowan, a professor at King’s College London and the director of the Drug Control Center in London, which is accredited by WADA. “That in itself is enough to pursue a case.”

In Landis’s case, the French national antidoping laboratory in Châtenay-Malabry performed the testing — not Cowan’s lab.

Still, Cowan said, most lab directors are careful to build a case against an athlete on much more than just one positive test, no matter how definitive a single test might be. A doping case in sports is treated like a criminal case, he said, with carefully gathered and documented evidence. He said the scientists at his laboratory retested a sample several times before announcing their results to the athlete and the authorities involved. He said they wanted to make sure their positive result was correct before moving on to the backup sample.

Landis said last week that he was expecting the worst because backup samples, or B samples, almost always confirm the initial result. But Kay said the B sample could come back negative.

“The carbon isotope was only mildly elevated,” he said. “We know, from a statistical standpoint, that the first result could have been a false positive.”

Testosterone can be administered by injection, pill, gel or time-released patch, like those mentioned in the Spanish doping scandal that implicated nearly 60 cyclists and others in the sport before this year’s Tour. Landis has denied using testosterone or any performance-enhancing drugs.

Nonetheless, Dr. Gary I. Wadler, an antidoping expert and associate professor at the New York University School of Medicine, said the evidence against Landis, taken as a whole, “would be hard to beat.”

He added: “Phase 1 was finding evidence from his body fluid that a doping violation occurred, and we have that. I don’t know how he will get around that.”

The carbon isotope test is used to look for testosterone abuse, and it came into use about six years ago, when companies produced equipment sensitive enough to do the test in urine samples.

It can cost about $300 more to test an athlete’s urine sample, but antidoping labs routinely use it when they have reason to suspect that an athlete was taking testosterone.

The test starts with an isolation of testosterone from the athlete’s urine. Then chemists determine the makeup of the carbon atoms that form the backbone of testosterone.

Ordinarily, carbon atoms are made up of six protons and six neutrons, giving them an atomic weight of 12. But occasionally, they have an extra neutron, giving them an atomic weight of 13.

By chance, soy plants are the source of most pharmaceutical testosterone. They tend to have slightly less carbon-13 than other plants that are more abundant in the human diet. Humans make testosterone from the food they eat, so their testosterone typically has more carbon-13 than the testosterone that drug companies synthesize from soy.

But these differences are tiny.

The test determines whether the testosterone in the athlete’s urine has less carbon-13 than another naturally occurring hormone in the urine, like cholesterol. The test is considered positive when the carbon isotope ratio — the amount of carbon-13 compared to carbon-12 — is three or more units higher in the athlete’s testosterone than it is in the comparison hormone. It is evidence that the testosterone in the urine was not made by the athlete’s body. Landis’s difference was 3.99, according to his own doctor.

“For me, that would be it,” said Donald H. Catlin, who runs the Olympic drug-testing laboratory at U.C.L.A.

The test could not, however, determine if someone had tampered with the urine sample or was negligent.

The lab that conducted the testing on Landis’s samples has previously been criticized for its handling of samples.

L’Équipe, a French sports newspaper, reported that samples taken from Lance Armstrong during the 1999 Tour de France were analyzed at the lab. Several of those samples, which were supposed to be used for research purposes only, later tested positive for EPO, an endurance-boosting drug.

The International Cycling Union commissioned a report that later cleared Armstrong of the doping allegations, partly because of the way the lab had handled the results. Armstrong lashed out at the lab, too.

But Christiane Ayotte, director of an antidoping lab in Montreal, said that the standards were lower for handling samples for research.

“It’s not fair to criticize them because of that,” she said. “When we’re talking about a routine analysis, the lab in Paris does high-quality work.”