The average American family washes and dries about 300 loads of laundry each year ENERGY STAR doesn't rate dryers because their efficiency has been about the same for years Maintenance will not do much to make a washing machine more efficient Only products that have earned the ENERGY STAR are certified independently to save energy ENERGY STAR-certified clothes washers use about 25 percent less energy and 45 percent less water than regular washers You can save $490 over the lifetime of an ENERGY STAR-certi

Your energy-efficient washing machine could be full of bacteria

Switching to cold water will get your clothes clean, but it won’t sanitize them, report finds

You fill it with soap and water about 300 times a year, so it must be clean. Right? A case out of Germany, published by the American Society for Microbiology, says no.

After babies in a German hospital’s neonatal intensive care unit were found to have multidrug-resistant pathogens on their skin, inspectors went to work to find out why. 

The incubators and health care workers all tested negative, but Klebsiella oxytoca kept appearing on the babies. “Klebsiella oxytoca is emerging as an important bacterial isolate causing hospital-acquired infection in adults and having multiple drug resistance to commonly used antibiotics,” the National Institutes of Health wrote.

» Staph infections: How they spread in hospitals and how to avoid them

The source of the bacteria was finally traced to the detergent drawer and rubber seal of the energy-efficient washer in the hospital’s laundry room. After the washing machine was removed, the contaminations stopped. They have not recurred.

The case report notes the domestic washing machine at the hospital was not part of the institutions main laundry room. It was near the nursery for mothers to wash their clothes, and nurses used it to wash the knitted hats and socks they put on the babies.

Energy-efficient washers are designed to clean in water that is cold or warm, saving the consumer money. The Department of Energy even recommends using cold water to do your laundry whenever possible.

» 5 ‘clean’ habits that actually make your kitchen germier

But, as CNN reports, studies have found the temperature needed for effectively killing possibly pathogenic bacteria is 140 degrees F or higher, which is considered hot water. As we’ve become more environmentally conscious, however, we’ve lowered the temperature of the water to save energy (and money). In Europe, for example, colored laundry is usually washed at temperatures between 86 and 104 degrees. In China, South Korea and Japan, cold water is preferred.

"When you do your towels with a cold water wash it's hard to get them really clean because they're so thick," Dr. Charles Gerba, a microbiology professor at the University of Arizona, told CNN. "You've got to use hot water wash and dry it really well."

If you don't, he said, "you'll get more E-coli on your face when you dry it with a towel than if you stuck your head in a toilet and flushed."

» Mother paralyzed after developing staph infection from makeup brush

» Hand sanitizers becoming less effective against some bacteria, study says

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