What’s more germy than a public toilet?It’s not a subway car handrail. It’s the shopping carts in grocery stores, according to a study last year that measured saliva, bacteria, and fecal matter on shopping cart handles. Both store owners and customers have sought ways to combat the filthy carts, from disinfectant wipes to cart liners to snap-on handles, with limited success. The latest clean-cart idea looks like a mini-car wash and sprays the entire cart with a mist of peroxide solution.PureCart Systems says their machines kill 99 percent of germs on carts.

More than 20 supermarkets across the country have installed PureCart machines, which cost about $8,000 a year. The machines appear to be popular with shoppers, especially those with young children. And with good reason: Among babies, contact with raw meat packaging is the second leading cause of Salmonella infection. Only reptile exposure is more dangerous. “[Kids] don’t necessarily have the best sanitary habits,” microbiologist Chuck Gerba said. “And you’re putting your broccoli right where the kid’s butt was.”

For more mature shoppers, experts say the best bet is still handwashing, though recent studies indicate your fellow shoppers probably aren’t taking that advice. So if your local supermarket doesn’t have a PureCart machine yet, check Google Flu Trends before heading out the door.

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Image: flickr / JaeYong, BAE