New evidence that flushing your toilet with the lid up is a public health hazard

Summary:A study of lid-less toilets in hospitals confirms that toilets are little volcanoes of bacteria.

A study of lid-less toilets in hospitals has revealed an uncomfortable truth that could apply to us all: Flushing the toilet with the lid up sprays a fine mist of bacteria-laden water into the air, which can settle on every surface on the bathroom, including your toothbrush.

It's a process long known to hygiene experts, and it's called aerosolization. Mythbusters did a segment on it and concluded that while toilets with lids up do spray water all over the bathroom, the risk associated with this process was negligible.

This newest study suggests that's not the case when anyone using the toilet is sick, however, as in a hospital setting. Specifically, elderly individuals carrying the bacterium C. difficile might transmit it through lidless flushes. C. difficile infections are on the rise; this might be one reason why.

Photo: Jim Fischer

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Topics: Innovation


Contributing Editor Christopher Mims has written for Scientific American, WIRED, Popular Science, Fast Company, Good, Discover, Slate, Technology Review, Nature and the Nicholas Institute for Environmental Policy Solutions at Duke University. Formerly, he was an editor at Scientific American, Grist and Seed. He is based in Washington,... Full Bio

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