Sochi: Drugs cheats can run but they cannot hide as testers can wait for years to retest samples that will eventually root out any doping offenders, World Anti-Doping Agency chief Craig Reedie said on Friday.
The International Olympic Committee is re-testing samples from past Games years later, using more advanced methods than were available at the time or looking for substances that could not be traced during initial testing.
The practice has led to the discovery of more cheats, including medallists from the Athens 2004 Olympics as well as the Beijing 2008 Games.
"Athletes are slowly beginning to understand that if you freeze samples for eight to 10 years, anything they can try and cheat on now, or try and get through under the radar or what not, isn`t likely to work," Reedie told Reuters in an interview.
"So it`s going to be embarrassing if they`re caught at any time," he said at the start of the Sochi Winter Olympics.
"You don`t want it to happen here but it might happen at a later date, so the package is pretty comprehensive."
Earlier on Friday the Estonian former Olympic cross-country champion Kristina Smigun-Vaehi confirmed she was being suspected of doping at the Turin Olympics after IOC re-tests of samples from those 2006 Games were completed late last year.
Reedie said Russia would be equally effective during Sochi despite a near-suspension of a Moscow laboratory in November - which led to the creation of another lab in Sochi - and a spotty doping past in the country.
"They invested very substantially in their testing process, they invested very substantially in the new laboratory," said the Scot, who is also an IOC vice president.
"I think the science was all right but it was the processes that were doubtful and that has led to the establishment of the satellite laboratory here (in Sochi), which is full of international helpers, top people and advice.
"So from that point of view I think there has been a really serious improvement and I hope it continues."
He said Russia, staging its first Winter Olympics, was trying to educate athletes and not just catch those who take banned substances.
Leading biathlon medal hope Irina Starykh failed a drugs test and was dropped from the team days ago in what was the latest high-profile doping case in Russia. In December another eight Russian athletes were banned following positive tests.
"I met with their sports minister ... and he explained that the whole effort wasn`t just doing more tests," Reedie said.
"It was trying to change the whole philosophy that doping didn`t make sense. This is a big country and that`s difficult to do but if they`re prepared to make that kind of step then I think that`s a step in the right direction."