It’s easy to see when surfaces and major appliances are dirty – but there are some smaller household items that could be putting your health at risk with E. coli, Salmonella, Staph and other fatal infections.
Toiletries like sponges, toothbrushes and hairbrushes may seem counterintuitive to clean – especially if you’re frequently replacing old brushes with new ones. But not so.
“People use them to clean – either their belongings or themselves,” wrote the American Society for Microbiology’s Dr. Madeline Barron.
“However, many of the household spaces, tools and appliances people associate with ‘clean’ are, from a microbial standpoint, far from it.”
Billions of bacteria in your palm
More than 50 billion species of bacteria can live on the surface of a 4×6-inch kitchen sponge. That’s because the sponge’s synthetic foam is constantly wet and able to absorb and host a lot of organisms, some of which are deadly.
“Gammaproteobacterial species (e.g., E. coli) are common members of the sponge microbiota. Food-borne pathogens, like Klebsiella pneumonieae, which can infect everything from the lungs to urinary tract, also inhabit sponges, along with various viruses and archaea,” Barron explained.
E. coli, Salmonella and Staph can survive for up to 16 days on a kitchen sponge, according to the society’s research. These infections cause thousands of deaths in the U.S. each year, with Staph infections tied to 20,000 associated deaths in 2017.
This exposure can occur even after just two or three uses, the Academy of Nutrition and Dietetics says. The academy recommends that people replace sponges every one or two weeks. You can tell if the kitchen sponge is bacteria-ridden if it has started to smell.
But there are ways to clean the sponge and kill the bacteria, according researchers at Michigan State University. Microwaving a wet sponge – a dry sponge can burst into flames – for one or two minutes should be sufficient to kill any bacteria. You can also wash the sponge in a dishwasher on its hottest cycle.
A sanitizing solution of warm water and concentrated chlorine bleach can also work, if you soak the sponge for one minute.
Dental disasters
A damp toothbrush may be working to keep teeth clean but dentists warn of danger lurking between the bristles before and after use. More than 10 million bacteria and fungi can hide in a single toothbrush, according to research from England’s Manchester University.
“That means there are considerably more bacteria on a toothbrush than an average toilet seat (which has 50 bacteria per square inch) or average public lavatory floor (two million bacteria per square inch),” the British Dental Journal wrote in 2016.
Some of those bacteria are the same as those found on sponges, such as E. coli, Klebsiella, the yeast infection-causing Candida and tooth decay-causing S. mutans, according to a study from Indian researchers in 2015.
A large part of that exposure may be based on where the toothbrush lives. It may be the easiest to place the toothbrush on the sink next to the toilet, but the toilet can expel fecal matter – and even harmful pathogens – with every flush.
Around 70 percent of used toothbrushes assessed by separate researchers in India were “heavily contaminated with different pathogenic microorganisms.”
So, what are we to do? There are best practices to follow that can help keep toothbrushes clean – although the immune system protects us from a lot of exposure to outside invaders.
Do not microwave a toothbrush, the American Dental Association warns. Instead, you can use a sanitizing device or soak the bristly end in a few tablespoons of bacteria-killing mouthwash or three percent hydrogen peroxide.
Also make sure to store toothbrushes in an upright position after use, allow them to air dry to prevent microbial growth, and close the lid to the toilet before you flush. Replace a toothbrush at least every three or four months, too. The effectiveness of the brush can degrade over time.
But, the association also says not to worry too much about exposure to bacteria. “While toothbrushes have been shown to harbor bacteria, there is no evidence that these bacteria cause adverse health effects. Nonetheless, some patients may be interested in sanitizing their toothbrushes,” it said.
Bad hair day
We may only use hairbrushes a couple of times a day, but have you ever cleaned it? Brushes can also harbor bacteria and even viruses, according to the dermatology and cosmetic surgery center Advanced Dermatology & Skin Cancer Associates, in addition to the dirt, dead skin cells, scalp oil and broken hair that gathers there.
The scalp is a warm and moist environment that is hospitable to bacteria and fungi, especially if you use hair oil or sweat a lot.
“We are mammals, we are covered with hair follicles and we have a normal amount of skin flora (bacteria, fungus and mites) that live on our bodies, in harmony with us,” Purvisha Patel, a board-certified dermatologist, said in a statement shared by the center. “Some people have more than others, some people are more susceptible to organisms than others.”
There also could be Staph in the brush, she said. “Staph in particular is a bacteria that lives in our nares/noses, Staph is commonly transmitted from person to person through hairbrush use, resulting in pustules and boils on the skin and scalp. Of course, there is lice as well,” warned Purvisha.
Using a dirty hairbrush can lead to dandruff and more greasy hair, redepositing scalp oil and what else has gathered on the bristles back onto the head.
That’s why “you should clean your hair brushes once every other week,” Michael Dueñas, a celebrity hairstylist, told Seventeen.
There are a couple of ways to clean the brush. First, make sure to get all of the hair off. Then, wash the brush with soapy and warm water, dish soap or a mild shampoo.
You should do this fairly often, according to celebrity hairstylist Irinel de León.
“To keep the brush cleaning a little less cumbersome, clean out the hair accumulated in your combs and brushes after each use. This will keep the bristles free of dead hair and be less of a clean up when it comes to washing them,” she advised in a post shared by hair and body care company Ouai.