The Langone Medical Center confirmed on Wednesday that Smilow Research Center, one of NYU’s animal testing facilities, was one of the many structures damaged by Hurricane Sandy.

The flooding resulted in the loss of lab mice and rats, as well as tissue specimens and cells in the center’s heart disease, neurodegeneration and cancer research facilities.

“Animal resource staff was on site continuously to mitigate the damage from the storm, but due to the speed and force of the surge, animal rescue attempts were unsuccessful,” the medical center said in a statement. “This facility is a barrier facility that is 'super clean,' which restricts the movement of animals in and out of the facility.”

NYU added that it was “deeply saddened by the loss of these animals' lives and the impact this has on the many years of important work conducted by our researchers.”

Michelle Krogsgaard, a cancer biologist at NYU's Smilow Research Center, spoke to ABC News about the disaster.

“It's so horrible, you don't even want to think about it,” she said. “All the work we did, all the time and money, we're going to have to start all over.”

Not only is the loss a tragedy for scientists who had been amassing research at the center for years, it could be detrimental for PhD students, whose limited research may not pay for them to stay on and redo the research they’ve done so far.

NBC News interviewed Ashley Seifert, who researches tissue regeneration at the University of Florida in Gainesville. A transgenic mouse can take years to breed, and a student three years into their research may not have time to start over. Funding and grants are very competitive, and researchers’ careers depend on successfully publishing their work.

“If I were to lose all my mice in one fell swoop, I'm basically starting from scratch and have lost three years of work,” Seifert said.

The center was finally opened on Wednesday to allow scientists a chance to salvage what they could from the 13th floor lab.

It is still unclear exactly how much was lost, and how much can be rebuilt using genetic strains from other universities’ research facilities.