World 100 metres champion Torri Edwards has tested positive for a banned stimulant, the Chicago Tribune reported on its web site on Wednesday.
The newspaper, quoting sources familiar with the case, said Edwards had tested positive for nikethamide at a meeting in Europe earlier this season.
If the positive is confirmed by the testing of her B sample, Edwards could be disqualified for next month's Olympic Games in Athens, the newspaper said.
Edwards finished second in the 100 metres at the U.S. Olympic trials on Saturday and is scheduled to compete in the 200 metres this weekend.
The Tribune said that under the new World Anti-Doping Agency code, a first offence for nikethamide could bring a suspension of up to two years, unless the athlete can prove its use was inadvertent. In the latter case, the athlete would get a public warning and loss of results for the competition in which the positive test occurred.