INDIANAPOLIS, AUG. 12 -- Dr. Robert Voy, the chief physician for the U.S. Olympic Committee, said he is conducting an official inquiry into drug-testing procedures at the Pan American Games.

Several athletes complained that at least one trailer at which urine samples were taken was unsanitary, and that there was a lack of fluids available. There were reports that some of the medal winners refused to give urine samples as a result, but physicians would not comment on that.

Dr. Ronald Blankenbaker, a physician for the Games' committee, said, "I'd have to say that any difficulties we've had up to this point were not necessarily unexpected. When you have volunteers, it is hard to reach the high levels of sophistication required {during the first few days} . . . The volunteers are very professional, good people who are performing the best they can."

The United States' refusal to allow a former Chilean secret policeman to compete in the Pan American Games jeopardizes Alaska's chances to host the 1994 Winter Games, an Olympic official said.

State Department counselor Edward Derwinski met with Mario Vazquez-Rana, the president of the Pan American Sports Organization, to discuss the State Department's refusal to grant a visa to Francisco Zuniga, a pistol shooter who wants to compete for his country in the Pan Am Games.

Olympic officials warned there is more at stake than a simple visa. Vazquez-Rana, who is also president of the Association of Olympic Organizing Committees, said that if athletes could not be guaranteed visas for competition in the United States, the IOC would likely reject Alaska's bid for the Winter Games.

"It will be very difficult for Alaska to win the Games," Vazquez-Rana said.

The State Department determined that allowing Zuniga to enter the United States would be "prejudicial to U.S. human rights and anti-terrorism policies," said spokesman Charles Redman.