WASHINGTON - Two minutes in a microwave oven can sterilize most household sponges, U.S. researchers reported on Monday.

A team of engineering researchers at the University of Florida found that two minutes of microwaving on full power killed or inactivated more than 99 percent of bacteria, viruses or parasites, as well as spores, on a kitchen sponge.

A shopper looks at microwave ovens on display in a file photo. Two minutes in a microwave oven can sterilize most household sponges, U.S. researchers reported on Monday. [Reuters]

"People often put their sponges and scrubbers in the dishwasher, but if they really want to decontaminate them and not just clean them, they should use the microwave," said Gabriel Bitton, a professor of environmental engineering who led the study.

Writing in the Journal of Environmental Health, Bitton and colleagues said they soaked sponges and scrubbing pads in raw wastewater containing fecal bacteria such as E. coli, viruses, protozoan parasites and bacterial spores.

Then they used a common household microwave oven to heat up the sponges. It took four to 10 minutes to kill all the spores but everything else was killed after two, they said.

"The microwave is a very powerful and an inexpensive tool for sterilization," Bitton said.

At least 76 million Americans get sick from food borne microbes every year, according to the U.S. Centers for Disease Control and Prevention, and 5,000 people die from them.

Kitchens are a common source of these illnesses.