(CNN) – The mistakes that led up to an anthrax exposure incident at the Centers for Disease Control in June are now the focus of a hearing on Capitol Hill.
CDC Director Tom Frieden was called to testify before the House Committee on Energy and Commerce. He addressed concerns from lawmakers about lax lab safety at the CDC.
"The fact that it appears that no one was harmed, and that there were no releases does not excuse what happened,” Frieden said. “What happened was completely unacceptable, it should never have happened. If I leave you with just one thought about today’s hearing as it relates to CDC it is this: With the recent incidents we recognize a pattern at CDC where we need to greatly improve the culture of safety. And I'm overseeing sweeping measures to improve that culture of safety."
A CDC investigation concluded no lab workers were infected by anthrax in the incident, but admitted to lapses in lab safety protocol.
Frieden also testified that he has “closed the two laboratories that were involved in this situation until we’re sure they can be reopened safely.”
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