Microwaves zap sponges clean Two minutes in a microwave oven can
sterilise most household sponges, US researchers report. A team
of engineering researchers at the University of Florida found
that 2 minutes of microwaving on full power killed or
inactivated more than 99% of bacteria, viruses or parasites, as
well as spores, on a kitchen sponge. "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," says Gabriel Bitton, a professor of
environmental engineering who led the study. Writing in the
Journal of Environmental Health, Bitton and colleagues say they
soaked sponges and scrubbing pads in raw wastewater containing
faecal bacteria such as Escherichia coli, viruses, protozoan
parasites and bacterial spores. Then they used a common
household microwave oven to heat the sponges. It took 4-10
minutes to kill all the spores but everything else was killed
after 2 minutes, they say. Spores of the food spo