The Top 10 Grimiest Spots in Your Home, According to Science

The world can be quite the grimy place, with bacteria and viruses lurking everywhere you turn. So how to protect yourself from a world teaming with germs? Practicing cleanliness is the only way. Perhaps you've already adopted some clean habits such as avoiding touching public restroom door handles, sanitizing your hands after you get cash out at the ATM, or hitting elevator buttons with your elbow to minimize the amount of bacteria with which you come into contact. But did you know that most of the germs you encounter won't be found in public spaces but on some of the most commonly used surfaces in your own home? So what are the grossest spots in the house and, more importantly, how do you clean them? Read on to discover the 10 dirtiest places at home—some of which you may not suspect.

  1. Kitchen Sponge

    Clean a Dirty Sponge

    Stop! If you're on after-dinner dish duty, you might want to think twice before reaching for your trusty kitchen sponge. According to a 2011 NSF household germ study, there's an average of 321,629,869 microorganisms living in every gram of your used dish sponge. Yuck! To clean up your dish washing routine, clean your sponge each day. You can kill bacteria with heat by microwaving a damp sponge on high for one minute, or by soaking it in a solution of water and a small amount of bleach. Ultimately, to effectively combat grime you may need to replace your sponge more frequently. If you'd rather not pay to replace yours, switch to a dish rag and toss it in the wash frequently to zap germs.

  2. Video Game Controller

    How to Clean Video Game Controller

    As it turns out, there’s more to risk than Princess Peach’s freedom when playing video games—you can also risk your health. Researchers at UNICEF and Domestos found that there were 7,863 germs crawling over every 100 square centimeters of your game controller. Luckily, it's a cinch to blast away germs from this grimy surface. Just remove the batteries from the controller, scrub the crevices with a dry toothbrush. Then wet a cloth with a mixture of water and rubbing alcohol and rub lightly over the surface of the controller to sanitize.

    Related: 12 Clever Uses for Rubbing Alcohol

  3. Coffee Reservoir

    Clean Coffee Reservoir

    That morning cup of joe could be putting you in contact with a major amount of bacteria according to researchers at the NSF. Their scientists found that half of household coffee reservoirs play host to yeast and mold growth. Instead of swearing off caffeine, simply clean your reservoir by filling it with equal parts vinegar and water, and then set the coffee maker to brew. If you can't commit to frequent cleanings, consider switching to a dishwasher-safe French press, for a cleaner—and tastier—caffeine fix.

  4. Toothbrush Holder

    Clean Toothbrush Holder

    Polishing your pearly whites is an important part of your hygiene routine, but the very cleaning tools you use to brush could be spreading more germs than they eliminate. One-third of the household toothbrush holders studied by NSF had Coliform present—an indication that fecal matter may be contaminating the surface. Scrub, scrub, scrub to restore your toothbrush holder to a sparkling clean. Let it sit in a cup of vinegar for about an hour, then thoroughly rinse and dry before returning toothbrushes to their proper place. Prevent recontamination by practicing good hand washing and storing your toothbrushes a safe distance from the commode.

    Related: 10 Handy Household Uses for Vinegar

  5. Cutting Board

    Clean Cutting Board

    Though there’s some disagreement on which type of cutting board is more sanitary—wood or plastic—they all contain a lot of bacteria. According to Dr. Charles Gerba at the University of Arizona, there is 200 times more fecal bacteria on the average cutting board than a toilet seat—mostly from the raw meat you've been slicing and dicing. While you try to get that disturbing statistic out of your head, you can give your cutting board an extra scrub with good old-fashioned hot water and soap.

  6. Cell Phone

    Clean Cell Phone

    With all the hours you spend scrolling, texting, and tweeting, your cell phone can be one of the most germ-ridden things that you own. A 2012 study showed that there are about 2,700 to 4,200 units of bacteria found on mobile devices. To clean your germy phone, just mix up water and 70% isopropyl alcohol in a spray bottle, lightly spray a microfiber cloth, and swipe it across your screen and phone case about once a week.

  7. Stove Knobs

    Clean Stove Knobs

    When cooking dinner, you probably turn on the stove without even considering the nasty germs that may be lurking there. But did you know that these seemingly innocuous knobs may be one of the dirtiest places in your kitchen? It's true: Around one-third of stove knobs are filled with yeast and mold, according to a 2011 study. To banish the germs, remove your stove knobs and soak them in a solution of white vinegar and water to disinfect. If the stove knobs cannot be removed, simply spray the knobs with the natural cleanser and wipe down after 30 seconds to restore them to pristine condition.

    Related: 10 Unusual Uses for Your Cleanest Kitchen Ever

  8. Purse Handles

    Clean Purse

    Your purse goes everywhere with you—the store, the office, and maybe even the public restroom—so it’s not surprising that it picks up a lot of bacteria in its travels. According to a study by the hygiene experts at Initial, one in five handbag handles is home to enough bacteria to cross-contaminate other surfaces. Though it depends on what kind of bag you have, generally you can wipe them down inside and out with a disinfectant wipe or a bit of soap and water on a microfiber cloth.

  9. Kitchen Sink

    Clean Kitchen Sink

    The kitchen sink sees it all: raw chicken, used coffee grinds, and mystery leftovers. Because of the large amount of cooking activity that happens in or around it, the sink can get pretty gross. The NSF found that sinks have a germ count of 31,905 microorganisms per 10 square centimeters—that's 70,000 times more bacteria than what's living on your toilet handle! To prevent bacteria from growing in the sink, sprinkle baking soda and wipe down with a vinegar-soaked paper towel or pull out the big guns by using a commercial disinfectant.

    Related: 9 Handy Under-Sink Organizers to Buy or DIY

  10. Pet Bowl

    Sanitize Pet Bowl

    Sure, Fido won't hesitate to eat spilled food right off the floor but that doesn't mean he's immune to the bacteria lurking in your home. In fact, the yeast and mold that live in your pet's bowl bowl make it one of the dirtiest places in the home, says the NSF—and have the potential to make you or your pet sick. So do yourself and your dog a favor by running food and water dishes through the dishwasher on a regular basis to banish germs.

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