Top sprinters Tyson Gay, Asafa Powell and Sherone Simpson acknowledged Sunday that they had tested positive for banned substances.
Gay is the American champion in the 100 meters. Jamaica's Powell is the former world- record holder in the 100, while countrywoman Sherone Simpson has a gold and two silver Olympic medals on her resume.
The 30-year-old Gay, who won the world championship in the 100, 200 and 4x100 relay in 2007, took part in the U.S. Anti-Doping Agency's "My Victory" program — in which athletes volunteer for enhanced testing to prove they're clean — and his results never raised red flags. Until, that is, an out-of-competition test May 16 that yielded positive results for a banned substance, the identity of which neither he nor USADA CEO Travis Tygart would reveal.
Gay said his "B'' sample will be tested soon, possibly as early as this week.
The 30-year-old Powell, whose 100-meter record of 9.74 stood until Usain Bolt beat it in 2008, was calling for an investigation as to how a stimulant called oxilofrine entered his system and caused a positive test at Jamaica's national championships in June. Simpson, who tested positive for the same stimulant, said she "would not intentionally take an illegal substance of any form into my system."