- Darren Campbell says athletics should follow cycling's lead
- The British sprinters is an advocate of lifetime bans for drugs cheats
- The Olympic gold medalist speaking after Tyson Gay and Asafa Powell tested positive
- Campbell warns some athletes inadvertently take banned substances
Cycling is a sport with a dark doping past but the way it has cleaned up its act is a model for athletics to follow, says Olympic gold medallist Darren Campbell.
The retired British sprinter called for change after track stars Tyson Gay of the U.S. and Jamaica's Asafa Powell both tested positive for banned substances.
The legacy of doping still hangs over cycling and Tour de France leader Chris Froome has frequently had to answer questions over his performance during this year's race in the wake of Lance Armstrong's fall from grace.
But Campbell, who won 4 x 100 meter gold at Athens 2004, suggests the way the sport has clawed back its credibility is a lesson to the track and field community.
"Athletics needs to have a look at cycling and see how they handled the Lance Armstrong situation and how over time people started to believe in the sport again," Campbell, who won 4 x 100 meter gold at Athens 2004, told CNN.
"But this can't go on, eventually it will destroy the sport and it will mean younger fans decide they don't want to watch athletics anymore, and that would be disastrous.
"Everyone has come out and said 'Enough is enough.' We are nearly at breaking point. If we don't do anything it will be broken forever."
Campbell, who also clinched silver over 200 meters at Sydney 2000, has long been a supporter of lifetime bans for athletes who chose to take banned substances, a sanction currently not allowed under the World Anti-Doping Agency's (WADA) code.
But, while he is steadfastly opposed to the use of performance-enhancing substances, Campbell is wary of punishing those who inadvertently break the rules.
He is concerned that athletes who unknowingly take banned substances contained within nutritional supplements could be sanctioned unjustly.
He compares the situation with Britain's 'horse meat scandal' in which some foods advertised as beef were found to contain horse meat.
"How many people knew they were eating horse?" added Campbell.
"I think that's why we shouldn't just say 'OK, they're drugs cheats' and just forget about it.
"Imagine if they're innocent? Innocent in the sense that they didn't knowingly take it."
"I run a sports nutrition company. As an athlete myself, there was no way for professional athletes to take nutrition products with the safety of knowing there's not going to be cross contamination.
"I'm an advocate for lifetime bans, but I wouldn't want to see someone banned for life who hadn't knowingly done it."
News of positive tests for both Gay and Powell comes just weeks after Jamaican triple Olympic gold medalist Veronica Campbell-Brown was also provisionally suspended.
Campbell is pleased to see anti-doping authorities clamping down on athletes regardless of their stature.
"There isn't a case that high-profile athletes get a different level of treatment to anybody else," added Campbell. "If they are caught doping it will be highlighted and everybody will hear about it.
"In that respect it's definitely the way forward. I still feel that governing bodies need to get to the point where the deterrent is so big and so powerful that it stops people from deciding to take performance-enhancing drugs."
On Sunday, former world champion Gay said he was told by the U.S. Anti-Doping Agency that an A sample from an out of competition test taken in May had come back positive.
Gay didn't name the substance found in his system and added that he never knowingly took performance-enhancing drugs. He has pulled out of next month's world championships in Russia.
Powell, a former world-record holder from Jamaica, said he was caught for using the banned stimulant oxilofrine -- often found in dietary supplements -- that showed up in a test at last month's Jamaican trials.
"I don't have a sabotage story," Gay was quoted as saying by Reuters. "I basically put my trust in someone and was let down. I made a mistake."