It’s long been a problem for the nation’s hospitals: A staggering number of medical supplies — from surgical gloves to sponges to medications — go unused and are discarded after surgeries.

A study by researchers at the University of California, San Francisco has put a price tag on that waste: almost $1,000 per procedure examined at the academic medical center.

The research, published in the Journal of Neurosurgery, examined 58 neurosurgeries performed by 14 different surgeons at UCSF Medical Center, a leading academic hospital.

James Yoon, one of the principal UCSF researchers on the study, said they weren’t only looking at costs but also at the environmental impact of wasted supplies.

Operating rooms in the U.S. produce more than 2,000 tons of waste per day, he said. Part of the research involved identifying which surgeries generated the most waste. Spinal procedures, for example, are among the most wasteful, the researchers found.

There is little agreement on how hospitals should address operating room wastefulness. Each hospital or hospital system handles waste in its own way, Yoon explained.

Among the most unused and discarded supplies identified in the study were sponges, blue towels and gloves.

The researchers projected that wasted supplies could cost $2.9 million a year in UCSF’s neurosurgery department alone.

And that might be an underestimate: Nurses reported they were less likely to open disposable supplies when they knew they were under observation for the study.

As health care costs continue to skyrocket, it is important to look for ways to contain them, said Dr. Michael Lawton, a neurosurgeon at UCSF and one of the study’s authors.

Lawton, who was also one of the 14 surgeons observed in the study, said he performs about 400 surgeries per year. If nearly $1,000 per procedure is being wasted on potentially reusable supplies, about $400,000 could be saved per year — for just one surgeon.

“These savings could translate into teaching and research opportunities, and also allow more patients to come in” for treatment, Lawton said.