Research into testing for drugs in sport has been put back by up to two years by the International Olympic Committee's corruption scandal, a leading international expert said yesterday at a gathering of experts in Melbourne.

Professor Don Catlin, a member of the IOC medical commission, said last year's doping scandal in the Tour de France had been a key factor in prompting the IOC to take action.

But he said the impetus they hoped would be gained at a world conference on sports doping in Lausanne earlier this year had largely been overwhelmed by the IOC's own internal problems.

Ten IOC members lost their jobs after the exposure of a million-dollar vote-buying scam by the Salt Lake City bid team - hosts of the 2002 Winter Games - earlier this year.

Catlin, who founded the UCLA Olympic Analytical Laboratory, said drugs in sport was an "explosive topic" and was "the only thing that can really mess up the Games".

But he said Australia, host country of next year's Olympics, was a world leader in the area and praised the facilities at the Australian Sports Drug Testing Laboratory (ASDTL).

Catlin was damning in his description of cycling: "This sport is so dependent on drugs," he said. "It's not a clean sport, it's a tragedy."

He told reporters that funding in the fight against drugs in sport needed to be significantly boosted. "To me the whole area has been underfunded for years." He agreed that developing watertight tests for EPO and human growth hormones were key areas.

He said it was "50-50" whether or not there would be a test in place for growth hormones at next year's Sydney Games.

Two leading runners from last month's Comrades Marathon in South Africa, a Russian and a South African, have tested positive for illegal substances and face disqualification, sources said yesterday.