Athens:World 100 meters women's champion Torri Edwards' two-year suspension for failing a drugs test has brought US sprinters into the limelight for all the wrong reasons. The chief of World Anti Doping Agency (WADA) says it is high time that officials in the US take the blame for the spate of positive tests by its athletes. Most prominent in that list are Tim Montogomery and Marion Jones who are still battling allegations of wrongdoing. Worst offenders US can lay claim to have produced the top sprinters of all time but now they are also earning the tag of being the worst dope offenders. Torri Edwards became world champion when the title was stripped off her compatriot Kelli White who tested positive for a banned stimulant. Edwards can still compete at Athens if the court of arbitration for sport considers her appeal. She claims she bought a medicine in France and did not know the contents because the label was in French. 'Sleazy' affair The recent spate of positive dope tests by American athletes has forced the WADA to give the US track and field authorities a hard rap on the knuckles. "What they have demonstrated over the past few years, is a very serious problem and it is a very sleazy thing because it is not a case of an occasional athlete taking a cold medicine or a supplement by accident. These are concerted programmes designed by scientists, encouraged by coaches, used by athletes or with the expressed objective of subverting what should be fair competition. So it is a sleazy business," said Dick Pound, President, WADA. Banned list However, Pound a former Canadian Olympic swimmer gave full credit to the USADA or the National Doping Agency in the US. It was their efforts that forced an investigation into the designer steroid THG, a substance for, which almost half a dozen US athletes have tested, positive. Pound thinks that fans should not be put off by all these doping scandals. "They should be concerned that there are people out there cheating, but they should be delighted that we are catching them," said Pound. However, there are fears that the Athens Olympics could turn out to be the dirtiest ever. For the first time tests will also be carried out for HGH or the human growth hormone that explains why laboratories such as the one in Athens will be open 24 hours a day. Their task is to test thousands of samples of blood and urine for close to 400 substances that are on the banned list.