The Dirtiest 'Clean' Places

May 20, 2012— -- You expect some sports to be filthy—your kitchen floor, your garbage can, your toilet. But how germy are the things designed to keep you and your home clean?

Washing Machine

Even if your drawers are free of skid marks—please, guys—trace amounts of feces still cling to your dirty underwear, says Charles Gerba, a microbiologist at the University of Arizona. "If you wash a load of undergarments, you transfer about 500 million E. coli bacteria to the machine." This can contaminate other clothing items, which may harbor germs of their own. (For the dos and don'ts of boxers and briefs, read What She Thinks of Your Underwear. Because yes, she's looking. And yes, she cares.)

What She Thinks of Your Underwear

Wash most whites first, and use chlorine bleach.

"It sanitizes the machine," Gerba says.

Then dedicate a load to underwear, using hot water (150°F) and a color-safe bleach substitute.

Once a month, run an empty cycle with bleach to wipe out any lingering germs. This is especially important for front-loading machines; water tends to settle in the bottom of these machines, allowing bacteria to proliferate, Gerba says.

Dishwasher

Crusty scrambled eggs = bacterial breakfast.

"When you allow dishes to accumulate for a few days, growth of bacteria invariably increases," says Philip Tierno Jr., director of microbiology and immunology at NYU's Langone Medical Center and the author of "The Secret Life of Germs."

"And even if you can't see it, there is viable foodstuff in the rinse water to feed them."

Plus, the dishwasher's door gasket may be contaminated with fungus and black yeast.

"That outer rim never reaches a temperature high enough to kill everything off," Tierno said.

And that's to say nothing of what you're actually ingesting—find out how to clean—and avoid—The 10 Dirtiest Foods You're Eating.

The 10 Dirtiest Foods You're Eating

If you don't plan on running a load soon, rinse your plates with a mild bleach solution (a shot glass of bleach to a half quart of water). This kills surface organisms so you can let dishes accumulate, Tierno says. Use the same solution to periodically clean the gasket.

Toothbrush

A 2011 study in Microscopy Research and Technique found that nearly half of never-before-used brushes were tainted with bacteria. It gets worse when you put the bristles to work.

"Your mouth contains more than 500 different types of bacteria," Tierno says. And if you leave your brush sitting out, it could collect fecal bacteria. "Unless you have a low-flow toilet, aerosolized droplets splatter when you flush. They can go pretty far—up to 20 feet." Yum!

Regularly run your toothbrush through a clean dishwasher, using standard dish detergent. A 2011 study in the American Journal of Dentistry found that this method eradicated nearly all disease-causing bacteria.

Another option is to soak your brush in a mouthwash that contains cetylpyridinium chloride, such as Crest Pro-Health Complete Rinse, for 20 minutes; doing this can also beat bacteria, the study found.

To avoid flying feces, Tierno says, simply store your brush in a closed cabinet—and remember to stock it with The Best Toothpastes for You.

The Best Toothpastes for You

Sponge

"The sink is the dirtiest area in the kitchen," Tierno says, "and the sponge is the dirtiest item in the sink."

In a recent Simmons College study, nearly a third of dishcloths and kitchen sponges tested were laden with staph (including some with MRSA, the antibiotic-resistant strain of staph) twice the rate of contamination in toilet bowls the researchers swabbed.

hrow your wet sponges into the microwave and zap them on high for 1 minute.

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