ATHENS, Greece — The World Anti-Doping Agency will explain its methods of retrospective testing to European Union officials as part of an ongoing debate over privacy issues.

WADA vice chairman Arne Ljungqvist said discussions would focus on the eight-year statute of limitation that allows testers to keep frozen samples of athletes' blood and urine for reanalysis when new detection methods become available.

"I know that this is one of the matters that the European Union wishes to discuss with us," Ljungqvist said.

Ljungqvist is attending an anti-doping conference in Athens, organized by the European Union, that ends Friday.

Retro testing has boosted WADA's ability to catch drug cheats using scientific advances that may not have existed when the competition took place.

Last month, the International Olympic Committee announced that six athletes had been caught using the new blood-boosting hormone CERA in retests of their samples from the Beijing Olympics.

"CERA (testing) occurred just after the games, but other methods may take two, four or even eight years to develop," said Ljungqvist, who is also chairman of the IOC medical commission.

"So this eight-year statute of limitation is very important ... It's a very, very strong message that says: Don't do this, you will be identified. ... The possibility should make those who might cheat to think again: You may be caught, if not today, them tomorrow."

WADA introduced tougher testing guidelines this year that oblige more athletes to declare their whereabouts each day of the year — raising problems with the European Union over its privacy laws.

The anti-doping body amended its code this month to satisfy the EU, but Ljungqvist said the changes made no practical difference to testing procedures.

"What we are doing needs to be phrased in a particular way to satisfy the legal community," he said. "That is we could easily accept the amendments that were proposed because they did not in any way disturb our anti-doping activities."

The Swedish medical expert said the new rules inevitably met objections from athletes not used to rigorous testing, but conceded the agency may not have presented its case well to the public.

The new rules also require athletes to detail their whereabouts for an hour of each day to allow out-of-competition testing.

"I think what has been misunderstood, and perhaps we have not been so clever in explaining, is that this one-hour slot is not making (rules) more strict," he said. "But it gives athletes the opportunity to say at least then, they will be there.

"If you look at it, (complaints) mostly come from athletes who are not used to having out-of-competition tests. That's the sad fact."