July 6 (Bloomberg) -- Cycling teams are turning to internal doping tests to protect $100 million of sponsorships as drugs tarnish the Tour de France, which starts tomorrow in London.

Battered by drug scandals involving three former winners of the sport's premier event, squads backed by Deutsche Telekom AG's T-Mobile and Computer Sciences Corp. have begun testing their athletes as often as once every two weeks.

``Emergency measures are needed,'' said Jesper Worre, a former rider who organizes the Tour of Denmark. ``Professional cycling is bleeding. The general public has stopped following it, and sooner or later the television and press will stop being interested.''

Cycling is trying to rebuild credibility after Floyd Landis last year became the first Tour winner to fail a drug test, and 1996 champion Bjarne Riis admitted doping. Landis's team, backed by Phonak Holding AG, folded and others lost sponsors. Landis, whose test found elevated testosterone levels, denies wrongdoing, and his case is being reviewed by a U.S. arbitration panel.

Jan Ullrich, the 1997 champion, is one of 58 riders linked to a blood-doping ring in Spain. He retired from the T-Mobile team in February, saying the allegations against him were false.

Last July, T-Mobile renewed its sponsorship of the team only after replacing the squad's management and naming the former vice chairman of its U.S. unit, Bob Stapleton, as team manager.

``T-Mobile believes that sport should be kept clean, and will actively play a role in helping restore cycling's credibility,'' the company said in a statement at the time.

New Suspicions

On the eve of this year's Tour, cycling's ruling body is testing the ``B samples'' of several top riders after initial tests found evidence of doping, Pat McQuaid, president of the Union Cycliste Internationale, said this week.

Italian sprinter Alessandro Petacchi, who won five stages in last month's Giro d'Italia, is the latest Tour withdrawal on doping charges, his Team Milram said yesterday. Leonardo Piepol, the King of the Mountains winner in Italy, was also suspended yesterday by his Saunier Duval team for a positive test. Both riders were contesting the Italian race when tests were done.

Johan Bruyneel, manager of the Discovery Channel team that is part-owned by seven-time Tour champion Lance Armstrong, said the T-Mobile and CSC testing programs are an effort to deflect criticism about their links to the scandals. Riis is CSC's team manager, and T-Mobile sports director Rolf Aldag is one of six former team riders who admitted to doping during the 1990s.

``It's two teams who have been dealing with a scandal,'' Bruyneel said. Discovery Channel has conducted internal tests for 12 years, ``only we're not making too much noise about it.''

`Impossible to Cheat'

CSC says the difference between its program and others is that the team has hired an independent scientist, Dr. Rasmus Damsgaard of Bispebjerg University Hospital in Copenhagen, to oversee the testing.

``The bottom line is cycling needs to clean up its act as soon as possible,'' said Brian Nygaard, a spokesman for the Lyngby, Denmark-based CSC team. ``It needs to be impossible to cheat.''

CSC and T-Mobile say they are charting blood counts to determine whether riders are extracting their own blood, then re- infusing it to increase the number of oxygen-carrying red blood cells and improve stamina. Because there is no official test for such transfusions, the UCI only suspends riders for two weeks if it finds elevated blood counts.

T-Mobile will check blood profiles for its riders six times this season, and it plans carry out two other unspecified tests, according to a team statement.

Suspicious Changes

The Bonn-based squad last month fired Serhiy Honchar, a 36- year-old Ukrainian, as the result of internal tests, T-Mobile said June 29, without releasing the results. The testing revealed suspicious changes in his blood readings, McQuaid said.

Honchar denies doping and plans to sue T-Mobile, said Volodymyr Suprun, chief trainer of Ukraine's cycling team. Honchar couldn't be reached for comment.

CSC plans to conduct 30 urine and blood tests on each of its riders, with most of the checks done without advance warning, Nygaard said. The UCI will do as little as one surprise test per rider this year.

Internal testing will only be successful if teams keep the UCI informed of the results, said David Howman, director general of the Montreal-based World Anti-Doping Agency.

``In the 1970s and '80s there were doping tests in East Germany that cleared athletes to compete even though they were engaged in a huge doping program,'' Howman said.

East Germany

In cycling, teams have for years done in-house testing to make sure riders aren't caught by official controls, said former rider Jesus Manzano. The 2003 Tour rider, who confessed to doping a year later, said some squads carry equipment on their buses to track blood counts.

Team Milram does its own testing once or twice a month, said spokesman Andrea Agostini.

``The results are always negative and so there is no need to tell the UCI,'' he said. ``We do the tests because we want to fight against doping.''

Some of the 21 teams in the Tour may be slow to improve internal testing because they don't trust rivals not to cheat, Worre said.

``About 50 percent of the people in the teams don't believe in a clean sport, they don't think it's possible,'' he said. ``They say the right things about doping but they don't do the right things.''

To contact the reporter on this story: Alex Duff in Madrid at at aduff4@bloomberg.net

Last Updated: July 5, 2007 22:14 EDT