SAN JOSE, Calif. -- The furor over a newly detected designer steroid spread to the Olympics and other sports Friday.

Olympic officials said they will test for THG at next summer's Athens Games, and authorities in horse racing, skiing and rugby also are implementing such tests.

The International Olympic Committee said it would add tetrahydrogestrinone, or THG, to the list of banned substances included in its tests at the Aug. 13-29 games. THG already has turned up in the samples of several track and field athletes.

"The gap between the cheater and science is getting very narrow," said Denis Oswald, head of an IOC panel that made a three-day visit to Athens to inspect Olympic preparations. "We will use the latest technology to trace drugs which have the reputation of not being detectable."

The International Ski Federation said it will test for THG this season, which opens with men's and women's giant slaloms this weekend in Soelden, Austria. THG testing is set to begin next week at the Rugby World Cup in Australia.

Also in Australia, the horse racing industry has added THG to its testing of thoroughbreds' urine. Officials said frozen samples from previous tests also might be reviewed.

International track and field officials plan to retest about 400 urine samples from the world championships in August, and swimming's world governing body will consider retesting samples from its world championships this summer. The NFL also has said it might retest samples for THG. Major League Baseball has said it will be unable to retest samples taken this year.

The World Anti-Doping Agency will hold a symposium in Colorado Springs, Colo., Monday and Tuesday to discuss testing athletes out of competition. More than 30 delegates from national anti-doping agencies, international federations, testing laboratories and athletes will attend the meeting.

Though anti-doping experts say sports never will be completely clean of drugs, they are hailing the discovery of THG and the recent moves toward increased testing.

"Some would suggest that this is just another revelation and we're forever playing catchup [with the doping world]," said Dr. Andrew Pipe, chairman of the Canadian Center for Ethics in Sport. "But this is evidence we have a system in place and it is doing what it should, and we can expect to see more of these revelations on a worldwide basis."

Senators Joseph Biden, D-Del., and Orrin Hatch, R-Utah, introduced a bill in Congress on Thursday that would make THG and similar substances illegal under the federal Controlled Substances Act. Also included in the bill would be androstenedione, popularized by Mark McGwire.

Hatch authored the Dietary Supplements Health and Education Act of 1994, known as DSHEA, which removed many dietary supplements from premarket safety evaluations by the Food and Drug Administration.

Four U.S. track and field athletes tested positive at a meet this summer for THG, and Dwain Chambers, Europe's fastest man, flunked an out-of-competition drug test.

Chambers blamed his positive THG test on nutritional supplements he said were provided by a California lab, Burlingame-based Bay Area Laboratory Co-Operative. He said through an attorney that he had been assured by BALCO founder Victor Conte that all the supplements he was given were within international rules.

U.S. drug authorities were able to unmask THG after an unidentified coach gave them a used syringe containing a substance he claims he got from BALCO. Conte has denied being the source.

Dozens of top Olympic and professional athletes -- from baseball's Barry Bonds and Jason Giambi to boxer Shane Mosley -- have been subpoenaed to testify before a federal grand jury probing BALCO. Being subpoenaed does not imply wrongdoing.

BALCO was raided by the Internal Revenue Service and local drug agents in September. Conte's attorney has confirmed that his client is the target of the grand jury probe. The scope of the investigation is unclear, and federal officials have refused to comment.