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WASHINGTON, June 23 (Reuters) - A U.S. Senate health panel on Monday called on the Centers for Disease Control and Prevention for a detailed explanation of a safety breach that exposed as many as 84 people at three CDC laboratories to live anthrax, a deadly pathogen.
In a letter to CDC Director Dr Tom Frieden, members of the Senate Health, Education, Labor and Pensions Committee, which oversees biomedical research and the CDC, requested a briefing and written explanation for the events that led to the exposure.
"We request a detailed explanation of what happened, why established safety protocols were not followed or were insufficient to prevent such an incident," the letter said.
"The breach in safety protocol threatened the health and safety of CDC staff and raises serious concerns and questions with respect to the protocols and procedures that were followed at the biosafety labs."
Scientists at the CDC bioterror lab in Atlanta accidentally sent live samples of anthrax to labs with fewer safeguards. Dozens of personnel are being treated with a vaccine and antibiotics to stave off illness.
Investigations of the safety lapses are under way but an initial review of events at the first lab, known as a biosafety level 3 facility, or BSL-3, suggests that multiple procedures were violated.
The protocol for killing anthrax using a new chemical process required that scientists put the sample in an incubator and wait at least 48 hours to check for signs of life. Instead, they waited only 24 hours and when they saw no new growth, assumed the material was safe.
The Senate committee said it was concerned it did not learn of the incident until nearly a week after it was detected.
It is requesting an explanation for the events that led to the incident and of the security and safety protocols at the facility. (Reporting by Toni Clarke; Editing by Eric Beech and Jim Loney)