Mold On Toothbrush: Easy Tips To Clean & Prevent

For the vast majority of us, brushing our teeth is one of the first chores of the day. It’s also incredibly important if you want to keep a full set of teeth throughout your life.

So, what are you to do when you open your bathroom door, only to see your toothbrush has become moldy? Does it need to be thrown away or can it still be saved? What if you accidentally already brushed your teeth with a moldy brush, will you get sick? And why did it get moldy in the first place?

All these answers and more will be answered in this article, so, for all you need to know about mold growth on toothbrushes (manual and electric), keep reading.

Mold on toothbrush

Why do toothbrushes get moldy?

Toothbrushes grow mold and mildew for exactly the same reasons it grows anywhere else, the conditions are correct for it.

Much as fungi (which mold is a form of), can be a highly complex organism, its needs are fairly basic and not too dissimilar to our own.

As long as it has an acceptable amount of moisture for hydration, nutrients for sustenance, and preferably a temperature range between 60-80 degrees Fahrenheit, it will be able to spread very efficiently.

Now that we know what makes the ideal environment for fungi to grow, let’s take a look at how you may inadvertently be providing just that environment on your toothbrush.


I’m sure it won’t come as any great surprise that bathrooms generally have the highest humidity levels out of all the rooms in a property. The steam created by warm water, as well as pools created from people washing their hands, etc all add to the overall moisture levels in bathrooms, giving fungi all the moisture they could ever need.


You might wonder what fungi could possibly use for nutrition on your toothbrush, and I’m afraid the answer is a little grim. You see, even if you were to run your toothbrush under the tap after using it, there will still be tiny amounts of food particles, as well as skin cells that were shed from your gums and cheeks whilst brushing.

Dust particles floating in the air can also settle on your brush if it is not covered, and these are made mostly of shed skin cells, along with other organic materials.

Mold consumes dust by releasing enzymes that break down the organic particles and skin cells, it then absorbs any nutrients it can gain from them. As a bathroom is a place where people dry themselves with towels and comb their hair, there is always plenty of skin cells to go around for mold to consume.


Along with being one of the wettest rooms in a property, bathrooms are also frequently one of the warmest. This warmth comes from steam after showering and bathing, along with central heating to make the room more comfortable.

The most common thermostat setting for central heating systems in the US is between 68° and 76° Fahrenheit, which when combined with the high moisture levels and abundance of nutrition, puts bathrooms (and your toothbrush in particular), right in the Goldilocks zone for mold growth.

What does mold on a toothbrush look like?

In its initial stages, mold growth can be exceptionally difficult to spot, as the amount that can grow on the head of a toothbrush (for example), will be very small. Many of the most common strains also start life as powdery growth with white coloration, making it all the harder to spot.

Only after a few days to maybe even a week will it start to become more obvious that you are dealing with a fungal infestation, as when fungi develop, they can change in color and texture, making them easier to spot. Some strains grow in blue-green, olive green, brown, or even black coloration with powdery or velvet-like textures.

Telltale signs of growth include:

  • Pink or dark spots forming in small circular patterns
  • Black liquid with a slimy consistency forming around the base or handle
  • A musty smell that is often compared to old socks

Depending on the strain that is growing, you may spot different colors or textures other than those mentioned above, either way, no matter the strain, it will need to be thoroughly cleaned before it can be used.

What types grow?

The three most common strains of bathroom mold are:

  • Penicillium
  • Aspergillus
  • Cladosporium

These are the most commonly found strains in bathrooms and therefore are also the most likely to be growing on your toothbrush, but this list is not exhaustive, and many other strains could find your bathroom environment appealing and may establish a colony on your toothbrush.

Without proper testing, it is very difficult to be 100% accurate in determining which strain you are dealing with. The good news is that it is not important, as any strain must be removed as soon as it is spotted.

Can black mold grow on a toothbrush?

Yes, black mold (Stachybotrys chartarum), can grow on a toothbrush, either on the actual head, the handle, or the base (in the case of electric toothbrushes). Bathrooms are the most common area of a property to find black mold growing, and so if there is a high enough humidity level, your toothbrush isn’t cleaned properly on a regular basis and the room is at a steady 60-80° Fahrenheit, you can be certain that black mold can indeed grow on your toothbrush.

How fast can it grow?

Fungi can form incredibly quickly, in fact, if mold spores were to travel into a room that had all the necessary components (moisture, nutrients, etc), they would begin to create a colony and start to spread within only a few hours. Although at this point it would be invisible to the naked eye. Within a few days, small patches of circular growth or black spots would being to appear.

It is for this reason that fungi of any kind should be removed as soon as it is spotted and preventative measures taken to ensure it doesn’t reappear, as it is much easier to deal with a small amount of mold than it is to rectify large patches of growth.

Are the mold strains dangerous?

This is a tricky question to answer because there are many factors to consider. For example, the amount of mold that can grow on a toothbrush is very small, and in many cases, exposure to such a small number of spores would cause little issue.

However, for people with suppressed immune systems or those with allergies, exposure to even very small amounts of mold could result in allergic reactions and other serious symptoms.

One thing that can be said for certain, is that penicillium and aspergillus strains can produce mycotoxins, and accidental injection of these (if you were to brush your teeth with a moldy toothbrush for example), could lead to very unpleasant symptoms such as:

  • Nausea
  • Diarrhea
  • Vomiting
  • Breathlessness
  • Abdominal pain

Inhaling or coming into direct contact with fungi of any kind growing in a bathroom can also cause symptoms, most often in those with allergies. These symptoms can include:

  • Irritation to the eyes
  • Rashes and skin irritation
  • Breathlessness
  • Coughing
  • Runny nose

Even strains that do not produce mycotoxins and therefore are not considered to be toxic can still elicit these symptoms in those sensitive to them, so if you spot mold growing on your toothbrush, you need to remove it as quickly as possible.

What if you accidentally brush your teeth with a moldy toothbrush?

There’s no doubt that realizing you’ve brushed your teeth with a toothbrush brush that has mold on it is a fairly revolting experience, but the good news is that in most cases you won’t need to worry about this too much.

For most people, being exposed to a small number of fungi is unlikely to produce any symptoms at all. If of course after brushing you begin to experience unusual symptoms such as breathlessness, coughing, nausea, or gastrointestinal discomfort, you may be allergic to the strain on the brush, in this case, it would be worth consulting a medical professional. If instead, you have no symptoms, there is little need for medical intervention.

Can you get a fungal infection from a moldy toothbrush?

Yes, if you were to continue using a toothbrush that had mold growing on it, it could indeed cause a functional infection. This could cause an outbreak of Candidiasis, Candida albicans, or an oral infection. Either way, if mold growth is spotted on a toothbrush, it should not be used.

What is the black gunk around your toothbrush?

Black “gunk” around the base of a toothbrush or within its cup or holder is a sign of bacteria and fungi. This usually occurs when the water has been present for some time, and a mixture of proteins and minerals collects in the pools, providing a breeding ground for fungal and bacterial growth.

How to remove mold on a toothbrush

If only a small amount of growth has occurred on your toothbrush the brush can usually be saved. However, it needs to be cleaned very thoroughly to remove all traces, or as previously discussed, health complaints could occur.

In order to remove mold from a toothbrush, take your choice of the following methods:

Baking soda

Mix two teaspoons of baking soda to one cup of water then stir the mixture. Pour the solution into a bowl, then place your toothbrush into the liquid ensuring the entire brush is covered. Leave it to soak for a minimum of 20 minutes before allowing it to air dry.

Hydrogen peroxide

Place your toothbrush into a container such as a bowl or plastic dish. Cover the toothbrush in 3% hydrogen peroxide, again, ensuring the entire brush is covered. Leave it in the solution for a maximum of 15 minutes, but a minimum of 5 minutes. Before using the brush again, wash the head under warm water for 1-2 minutes.


Take a cup and fill it with distilled white vinegar, place your toothbrush head first into the cup, and allow it to sit in the vinegar for a minimum of fifteen minutes. The acidity in the vinegar is powerful enough to kill both mold and bacteria. Rinse the brush with cold water and allow to air dry. The smell of vinegar will disappear in a few hours.

Can you wash mold off a toothbrush?

You can “wash” mold off a toothbrush in the sense that you can use methods such as those listed above in order to remove it. However, it should be made clear that simply running it under the tap briefly before using it will not be sufficient to remove all traces of mold, so proper cleaning methods should be utilized.

Preventing mold growth on toothbrushes

Being able to remove mold once it has become established on a toothbrush is one thing, but preventing it from occurring in the first place is always preferable.

In order to make sure you don’t have to deal with this irritating situation, use the following tips.


Where and how you store your toothbrush plays a big part in how likely it is to grow mold. To prevent its growth, store your toothbrush as far away from the toilet as possible, preferably in a container that can be closed to prevent any bacteria from the toilet from being passed onto the brush, or any fungi spores landing on it.

If you store your brush in a cup, make sure this is kept as dry as possible and washed thoroughly at least once per week.

Keep it dry

Bathrooms have the highest moisture levels within a property, so keeping something dry seems like a tall order. However, there are a few simple things you can do to reduce the amount of water left on the brush after each use.

After rinsing, tap the brush against the side of the sink to remove excess moisture, then use a clean towel or cloth to wipe the handle dry. This will prevent water from dripping down into the brush holder.

Deep clean

At least once per week, you should deep clean your brush. This doesn’t have to involve anything fancy, and can simply be that you leave it to soak, head side down in a clean cup filled with water and 1 teaspoon of baking soda or one tablespoon of vinegar/lemon juice. This will be sufficient to kill bacteria and mold that may have begun to accumulate over the week.

Ensure there is plenty of airflow

Keeping the brush in a container so that it cannot be affected by airborne bacteria and fungi is certainly a good idea. However, you need to make sure there is adequate airflow within the holder, or moist air can become trapped with nowhere to escape. This water then condenses, giving mold and bacteria the hydration it requires. Find a container that has vent holes that allow moisture to escape, preventing condensation formation.

When should you throw out a moldy toothbrush?

As we’ve seen, in many cases a moldy toothbrush can be saved with a few simple cleaning techniques, but there are also points where cleaning the brush is simply no longer an option and it needs to be thrown away.

As an example, If you’ve come back from a holiday and taken a different brush with you, then see that in the time you’ve been away, a substantial amount of fungi has grown over your brush head and handle, it may well be wise to simply throw it away rather than trying to clean it. This is because it may be very difficult to remove traces of mold under this circumstance.

The American Dental Association suggests you should replace your brush (or brush head if electric) at least once every three months. This is to ensure the bristles do not start to wear down and be less effective, but also to prevent large amounts of fungal or bacterial growth from accumulating.

Electric toothbrushes

So far in this article, we have mostly discussed issues around fungal growth on manual toothbrushes, and although many of the same cleaning and prevention principles apply to both, we will now take a closer look at electric toothbrushes, as there are a few minor differences to consider.

Why do electric toothbrushes get moldy?

An electric toothbrush is just as likely to become moldy as a manual brush, in fact, you could say that they are more likely to gather mold and bacteria, but we will get into that in a second.

They can become moldy for the same reasons outlined above, high moisture levels in bathrooms, poor storage practices, and improper cleaning.

The reason I state that electric brushes have more potential to become moldy is due to their storage options. With a manual brush, many people have either a cup, hang them in a wall-mounted holder, or simply leave them by the side of the sink, and whilst these are not always great options, at least the head of the brush is allowed to fully dry.

With an electric brush, the heads are detachable so multiple people can use the same brush by swapping it over whenever they wish to use it. These heads are stored in a small tray with a lid. From my own personal experience, a large amount of water pools in these trays, and even after only one or two days, if the temperature is high enough in the bathroom, the water quickly starts to turn black and slimy.

This is also true for the stand that you place the brush in to charge up, as droplets of mineral and organic matter-filled water drip down the brush after use and pool around the base. Unless both the brush and the charging dock are dried fully after each use, this can very quickly begin to grow moldy.

How to clean mold from an Oral-B electric toothbrush?

Oral-B electric toothbrushes can be cleaned using the same methods as any other electric brush. To clean them thoroughly, use the following steps.

Step 1. After brushing, keep the handle turned on and rinse the head under warm water for several seconds.

Step 2. Remove the head and any other components from the handle and rinse these thoroughly too. For the head, whilst under running water, use your thumb to move the bristles, ensuring the water can remove any larger pieces of debris.

Step 3. If you are struggling to remove all debris or any “gunk”, that has accrued, a mild detergent can be used. Make sure all detergent is washed off before leaving it to dry. Repeat this process with the handle.

Step 4. Ensure the brush head and handle are fully dried, use a clean cloth if necessary. The handle can then be placed back on its charging dock and the head into its tray.

How do you clean an electric toothbrush with vinegar?

For a deep clean, you can use the acidity of vinegar to kill and lift mold and its stains from an old electric toothbrush. To do so, use the following steps.

Step 1. Remove the head and any other components and rinse them under a warm tap to remove the majority of mold or debris.

Step 2. Pour a half cup of distilled white vinegar into a cup or mug, then place the head and any other components into the liquid. If they are not fully covered, add more vinegar until they are.

Step 3. Leave the brush components and head to sit in the vinegar for at least 20 minutes to allow the acidity to kill the bacteria and mold.

Step 4. Remove the items and rinse under a cold tap to remove all traces of vinegar and mold residue.

Step 5. Thoroughly dry the head and components with a clean towel or cloth before leaving to air dry.

To clean a handle, pour a small amount of vinegar into a spray bottle, then apply a liberal coating. Allow the handle to sit for 10 minutes, then use a clean cloth to wipe it down and remove any residue. Any scent of vinegar will dissipate after a few hours.

How to prevent mold growth on electric toothbrushes

Preventing fungal growth on an electric toothbrush is similar to the tips outlined for a manual brush, however, there are a few small differences that we have highlighted below.


Electric toothbrushes usually come with their own charging dock and tray for the heads to be placed in. Ensuring that both the dock and tray are kept as dry as possible and are cleaned with a mild detergent, vinegar, or lemon juice at least once per week will kill and remove bacterial and fungal growth.

If possible, try to store your toothbrush in a position where it receives plenty of airflow and natural sunlight. The airflow will prevent moisture accumulation and the UV rays emitted from the sun will sterilize the brush and heads.


Keep a close eye on the humidity of your bathroom to ensure it stays below 55%. Moisture levels greater than this create the perfect breeding ground for fungi and bacteria.

Should the level reach greater than 55%, consider opening windows, doors or installing bathroom extract fans. In order to easily keep check of the humidity, place a hygrometer in the bathroom.


Clean the electric toothbrush handle, heads, and charging dock at least once per week in order to prevent bacterial and fungal growth. Deep clean the heads in vinegar at least once per week, and spray the handle with vinegar or lemon juice to sterilize it.


Toothbrushes are something we all use every day. Due to high moisture levels in bathrooms combined with organic matter accumulation, mold, and bacterial growth is very common. To prevent this, clean your toothbrushes (manual or electric), at least once per week, keep them as dry as possible, and try to keep the overall humidity level in the bathroom below 55%.

Chris Walker

Chris Walker has struggled for several years with mold after buying his own property. After finding the solutions to several issues around his home, he decided to create this site in order to answer as many questions about mold and mildew as possible to help others dealing with the same problems.

Recent Posts