Comparatively speaking, your toilet seat is actually quite clean. Best Life1 went on a deep dive to discover the dirtiest areas in your home where bacteria may be lurking. These surfaces are likely touched each day without a second thought. Some are just teeming with bacteria.
After years of being warned about the spread of the common cold on door handles, you may have guessed they are included in a list of the top 10 items. However, door handles, computer keyboards and your pet's bowls don't make the top five list of items with the most bacteria in your home.
While few things are grosser than a dirty toilet seat, researchers discovered the common toilet seat contains as little as 50 bacteria per square inch. This may sound like a lot, but consider the following household items, all of which contain far more germs per square inch.
Pitch the Kitchen Sponge
Your kitchen sponge, the very thing you use to clean your dishes, may be among the filthiest objects you have at home. Containing as many as 10 million bacteria per square inch, or nearly 200,000 times more than your toilet seat, your kitchen sponge is a veritable hotel for nearly 362 different species of bacteria.
In one study,2 researchers analyzed 14 used sponges and found 45 billion microbes per square centimeter. Dish sponges harbor the largest number of E. coli and other fecal bacteria in the average home, likely because they aren't replaced as they should.
A number of studies have confirmed kitchen sponges contain the highest number of bacteria on household products.3 Dish cloths are not far behind. Researchers analyzed 82 from five major cities in the U.S. and Canada, finding E. coli in a little over 25% of the towels, and salmonella in nearly 14%.4
Kitchen sponges are also possible sources of contamination in restaurants. In one study, researchers collected 201 sponges from restaurants and evaluated the total count of aerobic bacteria. They were able to isolate Pseudomonas, Bacillus, Streptococcus and Lactobacillus, revealing poor kitchen sponge sanitization practices.5
Think About Cleaning Your Cellphone
Microbiologists often refer to cellphones as petri dishes as they generate heat, live in the darkness of your pockets and often travel into the bathroom with you.6 You may not have given a second thought to taking your phone with you everywhere you go, from the dinner table to the doctor's office.
According to one survey,7 Americans check their phones nearly 47 times each day, affording ample opportunity for microorganisms to move from your hand to the phone. Emily Martin, Ph.D., assistant professor of epidemiology at the University of Michigan, believes cellphones may be so bacteria-ridden since people take them where they would normally wash their hands before doing anything else.8
While research varies on how many germs are actually on the average cellphone, one study9 found over 17,000 bacterial gene copies on the phones of high school students. Another study10 found health care workers’ mobile phones were a reservoir for potential pathogens, were rarely cleaned and often touched during or after examination of patients.
To reduce the number of bacteria you carry around on your phone, keep it out of the bathroom and consider washing your hands more frequently. You may also consider investing in a small ultraviolet light sanitizer to kill bacteria without using excessive heat or moisture.
To sanitize your phone at home you'll want to avoid using excess moisture that can damage the interior. Most glass surfaces have a coating to repel oils so using anything abrasive can scratch the surface permanently. Steer clear of window cleaners, compressed air, bleach, hydrogen peroxide or abrasive powders. Use these weekly steps to thoroughly clean your cellphone and case.11
- Unplug the phone and any attachments and turn it off. Remove any protective covers or cases to clean separately.
- In a small spray bottle mix a 1-to-1 ratio of 70% isopropyl alcohol and distilled water. Hard water contains microscopic minerals that can scratch the glass.
- Lightly spray a lint-free microfiber cloth. Never spray the phone directly and do not overwet the cloth as you may damage the electronics. Wipe the phone front and back.
- If there is buildup around small areas, such as around the attachment ports, buttons or camera lens, use a dry cotton swab or wooden toothpick to gently clean those areas. Once any buildup is cleaned, wipe the area again with a microfiber cloth slightly dampened with the isopropyl and distilled water mixture.
- While waiting for the phone to air dry completely, clean the cellphone case. Allow both to dry completely before reinserting phone.
Do You Clean Dishes in That Sink?
In a study conducted by the National Sanitation Foundation (NSF),12 the researchers found the kitchen sink had the second highest concentration of microorganisms in the home. In another,13 researchers found the bathroom sink had more than 1,000 colony forming units.
Another study14 of hospital sinks found dangerous bacteria growing along the drain pipes. The humidity and relatively protected environment makes for an ideal breeding ground, according to researchers.15 According to the NSF16 it's important to clean and disinfect your sink once or twice a week and sanitize drains and garbage disposal monthly.
Start by removing soap deposits, food stains, rust and water spots by scrubbing with baking soda.17 You can sanitize germs in your sink by plugging the drain and filling with warm water and either vinegar or vodka. White vinegar is made with acetic acid and a powerful cleaner to cut through grease and remove mildew and stains.18
Vodka is 80 to 100 proof alcohol and is highly antibacterial without any odor. Essential oils also have a wide range of medicinal properties, including having powerful antibacterial properties. When essential oils are added to vodka in a spray bottle, some can also enhance the removal of mold, mildew and musty smells.19
Tea tree oil, citronella, lemongrass, orange and Patchouli essential oils have particularly strong bacterial fighting properties.20 Once a week, fill your sink with hot water and vodka or vinegar and then quickly pull the drain to allow it to flush your drain pipes. This also helps remove greased along the drainpipes and keep your sink draining well. Consider using in your bathroom sink as well.21
What Is Getting Chopped on Your Chopping Block?
Cutting boards are another offender when it comes to harboring dangerous bacteria. Experts recommend having at least two cutting boards, one for foods safely eaten raw, such as fruits and vegetables, and the second specifically for cutting raw meat, poultry and fish. This helps avoid transferring bacteria.
Surfaces you use to chop your food may have bacteria including E. coli and Salmonella.22 Since plastic cutting boards have been easier to sanitize, they were often thought safer. That was until the 1980s when a UC Davis researcher investigated and found although they are easier to sanitize, cutting often nicks the plastic, giving bacteria a place to hide.23
Wood may be tougher to sanitize, but it does not nick as easily. The U.S. Department of Agriculture (USDA)24 hotline recommends washing your cutting board in hot soapy water after each use and allowing it to completely air dry before putting it away.
Bamboo cutting boards are harder and less porous than wood, absorb little moisture and resist scarring from knives. Importantly, replace your worn boards as they develop hard-to-clean grooves.25
Remote Controls Keep Bacteria Close
Your remote control is also covered in bacteria, mold and potentially infection-causing Staphylococcus aureus. And, if you don't clean your remote control, you can bet your hotel probably hasn't either. According to Katie Kirsch, who presented a study at the 2012 general meeting of the American Society for Microbiology while she was an undergraduate student at the University of Houston:26
"Currently, housekeepers clean 14 to 16 rooms per eight-hour shift, spending approximately 30 minutes on each room. Identifying high-risk items within a hotel room would allow housekeeping managers to strategically design cleaning practices and allocate time to efficiently reduce the potential health risks posed by microbial contamination in hotel rooms."
The researchers from the University of Houston discovered an average of 67.6 colony forming units of bacteria per cubic centimeter on hotel remote controls.27 This is 13 times the maximum acceptable level recommended in hospitals.28
You’ll want to use the same precautions cleaning your remote control as you do with your phone to avoid damaging the electronics. Remove the battery and clean with a cotton dampened with rubbing alcohol, removing any grit or grime around the buttons with a cotton swab or wooden toothpick. Allow it to dry completely before replacing the batteries.29
Using Nontoxic Cleaners Is Effective and Safer
Using nontoxic cleaners are as effective and safer than over-the-counter chemicals. Commercial sprays, wipes, scrubs and polishes often add toxins to your home environment instead of removing them. If you have ever felt nauseous, dizzy or gotten a headache after cleaning your home or using an air freshener, it is likely because of the volatile organic compounds (VOCs) emanating from the cleaners.
These chemicals irritate your eyes, nose and throat and over the long term can damage your liver, kidneys and central nervous system.30 You can't tell what types of toxic chemicals are in over-the-counter cleaning supplies because labeling is not required for all substances that may be in them. Even products labeled green, natural and organic may emit hazardous air pollutants.31
As previously mentioned, some essential oils have strong antibacterial properties and also add a fresh clean scent to your natural cleaning arsenal.
What Can You Do With Your Disposable Sponge?
Although many times it is possible to be thrifty and safe at the same time, it can take a bit of effort to keep a disposable sponge clean. Using a microwave oven on high may make the sponge smell a little better, but researchers have discovered potentially pathogenic bacteria on sponges from those who claim to routinely disinfect them.32
While you're not required to pitch a sponge you pulled from the package yesterday, replacing them once weekly is a good idea. Only you know how much you've used it and what it's been used for. Consider if it was used to wipe the baby's mouth, soak up milk on the floor or clean the sink drain as these actions have likely deposited a greater number of bacteria than you imagine.
According to the USDA,33 microwaving sponges properly may kill up to 99.99999% of bacteria, while running them through the dishwasher kills 99.9998%. Forbes34 offers three ways to sanitize your sponges, which may have varying results:
- Boiling them
- Microwaving
- Soaking them in bleach — one-fourth to one-half teaspoon of bleach per quart of warm — not hot — water for at least one minute
If you do choose to use your microwave, Michigan State University35 advises the sponge be completely wet when you do it, as it could catch fire or explode in the process if it isn't. The wet sponge should be placed on high for one minute and left to cool for up to 15 minutes so you don't get burned.