Microwaves can help keep kitchens germ freeThey can kill food bugs on sponges and scrubbers

24 January 2007

Microwave ovens are a ‘very powerful and inexpensive tool’ in the fight against germs that cause food poisoning, American researchers claim.

They found that putting household sponges and scrubbers in a microwave oven for two minutes killed more than 99 per cent of harmful bacteria – including E.coli, salmonella and a range of other bugs.

Gabriel Bitton, a professor of environmental engineering at the University of Florida, said: ‘Basically what we find is that we could knock out most bacteria in two minutes.

‘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.’

Fire warning

But fire chiefs have warned against sterilising dish cloths in the microwave after one man set fire to his kitchen.

The blaze broke out in Telford, Shropshire when the man put the cloth in his microwave on full power in a bid to kill bugs.

A spokeswoman for Shropshire Fire and Rescue Service said: 'Our advice is please don't do it, it is dangerous. Apart from setting fire to the microwave, you can scald yourself.'

In the US study, published in the Journal of Environmental Health, researchers soaked sponges and scrubbing pads in dirty water containing bacteria, viruses and parasites.

It then took two minutes of microwaving on full power to kill more than 99 per cent of the bugs.

Professor Bitton said it was likely that the heat, rather than the microwave radiation, killed the germs.

Sterilised

Sponges needed to be damp - not dripping - to attract enough microwaves to become hot enough to be properly sterilised.

The team also warned that the sponge needed to be completely damp to guard against the risk of fire.

Professor Bitton advised cooks to microwave their sponges every other day, adding: ‘The microwave is a very powerful and inexpensive tool for sterilisation.’