Members of a U.S. House subcommittee have suggested that the VA Pittsburgh Healthcare System retaliated against a former employee after she testified about the destruction of thousands of biomedical samples.

In a letter yesterday to Dr. James Peake, secretary of veterans affairs, two subcommittee members said that soon after Dr. Janet Stout appeared before the panel this month, VA Pittsburgh's director, Terry Wolf, issued a directive banning her from the premises without prior approval from Ms. Wolf's office.

"This directive appears to be punishment for Dr. Stout's appearance before this committee," Rep. Brad Miller, D-N.C., chairman of the Investigations and Oversight Subcommittee, and Rep. Dana Rohrbacher, R-Calif., wrote.

Saying that the panel "does not tolerate such retaliation by a federal agency against a witness of a subcommittee hearing," the congressmen asked that the VA provide all records related to a Sept. 11 e-mail sent by Ms. Wolf to VA officials about Dr. Stout, along with other information.

David Cowgill, a spokesman for VA Pittsburgh, said the health system would have no comment.

In her e-mail, Ms. Wolf said she had recently learned that Dr. Stout, a former employee, "has been seen on VA premises" and "still receives mail here. Both practices must be terminated immediately."

She said that without approval from her office, Dr. Stout should not be allowed on the health system's property and that any mail addressed to her should be refused or returned to the sender.

Dr. Stout said yesterday that she felt victimized by the e-mail, sent two days after she testified before the subcommittee, and that "obviously, it was a response to the hearing."

She said she had been at VA Pittsburgh several times in recent months to meet with colleagues for professional purposes. She said she resigned from the health system under pressure in January 2007 and remains a University of Pittsburgh faculty member.

While at VA Pittsburgh, Dr. Stout and her colleague, Dr. Victor Yu, were associated with its Special Pathogens Laboratory. They and other local researchers discovered a link between drinking water supplies, which can harbor Legionella bacteria, and the spread of Legionnaires' disease, a form of bacterial pneumonia that especially affects the elderly and people with compromised immune systems.

At the subcommittee hearing, Dr. Stout, Dr. Yu and their supporters portrayed VA Pittsburgh's closure of the lab in July 2006 as needless and the destruction of the samples in December of that year a tremendous loss for research.

VA Pittsburgh officials, however, testified that the lab was conducting unauthorized research and that the samples were destroyed because they were inappropriately identified.

Both Mr. Miller and Mr. Rohrbacher were critical of VA officials during the subcommittee hearing, and Mr. Miller later said he found much of their testimony "very hard to believe."