3 Reasons Why Your Bathroom Smells Like Rotten Eggs

A ‘rotten’ egg smell in the bathroom can be observed due to several reasons.

The obnoxious smell comes from a gas known as hydrogen sulfide, which is produced due to bacterial growth.

The gas that causes a bad smell can arise from different sources.

Reasons Why Your Bathroom May Smell Like Rotten Eggs

You need to first detect the source of the ‘rotten egg smell’.

Once you have identified the source of the smell, you can take action to get rid of the smell for good.

Here are some possible reasons:

Stale Water

The bad smell in the bathroom can rise due to contaminated water.

Water in the taps can get contaminated due to several reasons:

Faulty Hot Water Tank

Stale water can become an issue due to bacterial growth in the hot water tank, which creates a rotten egg smell as a result of hydrogen sulfide.

The bad smell can also be due to corroded magnesium anodes in the hot water tank.

To figure out if the tap water is contaminated, you must take the water sample from the hot side of the tap.

Bring the glass of water outside and check if it smells like rotten eggs.

Faulty Plumbing

Faulty plumbing can also create a foul smell.

If the smell is a result of faulty plumbing, you should contact a plumber to repair or replace the faulty fixture immediately.

Corroded Bathroom Pipes

Bacteria can grow inside corroded pipes. It can also grow inside the overflow outflow outlet pipes of the tub or sink in the bathroom.

You should check the water at different sources to confirm if the corroded pipes result in the rotten egg smell.

Dry P-Trap in the Sink

The rotten smell in the bathroom could also be the result of a crack or leak P-trap. Most sinks have a P-trap to which the drain pipe is connected.

Its function is to block harmful sewer gas from releasing back up through the drains.

The P-trap should have some water inside otherwise harmful gases will escape from the sink.

The water inside the P-trap prevents the buildup of harmful sulfide gas contaminating the bathroom.

P-trap can become dry due to a crack.

Moreover, the water may also have evaporated if the sink has not been used for a long time. If the P-trap dries up, harmful sulfide will escape outside, resulting in a foul smell.

Dirty Drain

If the water sample is clear, the source of the smell could be a dirty drain.

Bacteria accumulate in dirty sewer water.

A large number of bacteria in the drain water results in the release of hydrogen sulfide gas that causes the rotten egg smell.

Out Gassing

Outgassing is another reason behind the nasty smell of rotten eggs.

The term outgassing refers to the release of gasses by certain materials over time. It is common in newer products, particularly those that are made of cultured marble.

If your bathroom smells like rotten eggs after installing a bathroom fixture, the fixture may be the cause of the foul smell.

Eliminating Rotten Eggs Smell in the Bathroom

After you have identified the source of the foul smell, you should address the source to eliminate the smell from the bathroom.

Here are some tips for getting rid of the smell of rotten eggs from the bathroom.

Call a Plumber

If the source of the foul smell is faulty plumbing you should call a plumber to look at the problem.

The plumber will examine the pipes, water heater, or P-trap and perform the required repairs.

If the heater is causing a foul smell, the plumber will repair or replace the corroded part.

The plumber will replace the anode rode with an aluminum rod. This will help in eliminating the four smells from the heater.

You should also consider replacing the faulty heater in case of extensive corrosion inside the bathroom fixture.

Ask the plumber to replace any old corroded pipes with new ones.

The plumber may also check blockage in the water softener and carry out the recommended repairs.

Disinfect Water

You should consider disinfecting the water if the foul smell is due to dirty water.

Chlorination of water can also kill harmful bacteria from the water tank.

You can also use common household bleach to disinfect water in the water tank.

Bleach contains the active ingredient hypochlorous acid that can kill the bacteria. Here are the steps to use bleach to disinfect water.

  • Step 1: Mix the bleach and water at a ratio of 1:100.
  • Step 2: Put the bleach mixture in a spray bottle.
  • Step 3: Spray the bleach into the overflow hole of the water tank.

Let the solution in the tank for about one or two days. Check if the rotten smell has stopped.

Clean the Drain

You should clean the gunk in the bathroom sink drain. This will eliminate the bacteria that is causing the foul smell.

Here are the steps for cleaning the gunk from the bathroom drain.

  • Step 1: Unscrew the pivot rod nut and remove it from the sink drain.
  • Step 2: Next, you should remove the pop-up stopper from the drain.
  • Step 3: Dip a toothbrush in vinegar and clean the pivot rod and the stopper. If these are too dirty, you should clean them in the laundry tub using a Clorox bleach and water solution.
  • Step 4: Now, roll a paper towel and use an appliance brush to push it down the drain.
  • Step 5: Scrape the drain sides using the brush to clean the area. Make sure to clean the biofilm inside the drain.
  • Step 6: Next, you should unscrew the goose-neck from the wall drain, and use a spoon to scrape out any sediments.

Reinstall everything once you are done cleaning.

You should then pour hot water inside the drain to remove any sediment and disinfect the drain.

Clean the P-Trap

Buildup inside the P-trap will force sewage water to flow upwards. You should clean the fixture to remove the sediments settled inside.

Once you have cleaned the P-trap, you should pour hot water to remove residual gunk.

In case the fixture has a crack, you should call a plumber to replace it.

Clean the Vents

If cleaning the drain or repairing the plumbing fixture does not result in the elimination of the rotten egg smell, you go to the house roof to find out if the smell is due to a clogged vent.

Remove any obstruction in the vent. You should consider calling the plumber if you can’t see what is blocking the vent.

Calling the plumber is important as cleaning the clogs in the bathroom vents can be dangerous.

If you decide to clear the clog yourself, you should take safety precautions when cleaning the vent.

Make sure that you wear gloves, goggles, and a helmet when cleaning the vent. Also, you should wear a boot that will give you solid support on the roof.

Clean the Sinkhole

Bacteria can also accumulate inside the sinkhole. You should remove the screw and clean the sinkhole using water.

Once you have cleaned the sink, you must pour about half a cup of bleach down the water pipe.

Another option to clean and disinfect the sinkhole is by using a solution of vinegar and baking soda. You can use this solution to clean the sink and the pipes.

This will effectively remove the buildup of bacteria, thereby eliminating the rotten egg smell.

Diagnosing the Source

Inspection of Pipes and Drains

One of the first steps in identifying the source of a rotten egg smell in your bathroom is to inspect the pipes and drains. Over time, gunk can accumulate in drains and lead to the growth of bacteria, which produce a foul odor. Make sure you:

  • Check for any clogs or blockages in your drains
  • Clean the gunk in the bathroom sink drain
  • Inspect plumbing fixtures for signs of leakage or corrosion

Checking Vents and Traps

Another reason your bathroom may smell like rotten eggs is due to issues with vents and traps. The P-trap, a curved section of pipe under the sink, prevents sewer gas from entering your home by trapping water. If the water in the P-trap evaporates, sewer gas, including hydrogen sulfide, can escape and cause the foul smell. To address this issue:

  • Pour water down your drains to refill the P-trap
  • Ensure that vents, which help regulate air pressure in the system, are not clogged or blocked
  • Investigate any broken or malfunctioning plumbing traps

Evaluating Water Quality

Lastly, rotten egg smells in your bathroom could also be due to contaminated water. The presence of organic matter or bacteria in your water supply can lead to the production of hydrogen sulfide gas, causing the rotten egg smell. In this case, you’ll want to:

  • Conduct a water test to identify harmful bacteria or contaminants
  • Flush your water heater to remove any sediment buildup
  • Install a water filter or treatment system, if necessary

By thoroughly inspecting your pipes and drains, checking your vents and traps, and evaluating your water quality, you can effectively pinpoint the source of the rotten egg smell in your bathroom and take appropriate measures to eliminate it.

Is Smelling Bathroom Harmful to Health?

As mentioned before, when the bathroom smells of rotten eggs, it is actually due to sulfide gas.

In small quantities, the gas is unlikely to cause any health issues. However, a concentrated amount of gas can result in different health complications.

Concentrated exposure to sulfide gas can result in dizziness, headache, nausea, and unconsciousness, according to the International Association of Certified Home Inspectors (interNACHI).

Exposure to large quantities of sulfide gas can make you feel faint.

It increases the risk of getting seriously injured due to falling on the hard surface inside the bathroom.

You should not let the rotten egg smell linger in the bathroom.

Long-term exposure to even small quantities of gas in the bathroom can result in breathing problems.

If you smell the distinctive smell of the rotten egg, you should take steps to address the source of the smell.

Frequently Asked Questions

What could be causing a sulfur smell in my bathroom?

A sulfur smell in your bathroom could be caused by several factors. One common reason is contaminated water, which could result from a faulty hot water tank.

Bacterial growth in the hot water tank can create a rotten egg smell due to hydrogen sulfide. Another possible cause is a dry P-trap, which can allow sewer gases to escape through the drainpipe when it runs dry.

How can I eliminate the rotten egg odor coming from my sink?

Here are a few effective ways to remove lingering smells from your bathroom sink:

  • Using boiling water
  • Using a plunger and boiling water
  • Applying a vinegar and baking soda mixture
  • Using hydrogen peroxide
  • Utilizing specialized cleaning solutions

What steps should I take if my bathroom smells like sulfur?

If you detect a sulfur smell in your bathroom, take the following steps:

  1. Identify the source of the smell (sink, shower drain, or toilet).
  2. Apply appropriate cleaning and odor removal methods mentioned above.
  3. Inspect your hot water tank for bacterial growth.
  4. Make sure the P-trap is properly functioning to prevent sewer gases from escaping.

Could infrequent use of a bathroom lead to a rotten egg smell?

Yes. A bathroom that isn’t frequently used can develop a rotten egg smell due to a dry trap. The water in the pipe can dry up, allowing sewer gases to back up into the toilet and out into the room.

Why does my shower drain emit a smell reminiscent of rotten eggs?

A shower drain smelling like rotten eggs might be caused by a dry P-trap, which can no longer block sewer gases from escaping the drainpipe.

This often occurs in guest bathrooms that aren’t used frequently, as the water in the trap evaporates. To address this, simply run water into the drain to refill the trap.

What are common solutions for a sour or sulfur-like smell in the bathroom?

Some common solutions to eliminate a sulfur-like smell in the bathroom include:

  • Cleaning the sink and drain with boiling water or a vinegar and baking soda mixture
  • Running water through infrequently used drains to refill the P-trap
  • Inspecting your hot water tank and addressing any bacterial growth


The rotten egg smell in the bathroom can be attributed to faulty plumbing, dirty drain, outgassing, or contaminated water.

You should know about the source of the smell so that you can take action to eliminate the foul smell.

The tips mentioned in this blog post will help you detect the source and eliminate the smell from the bathroom.

The potential side effects of a contaminated bathroom can be serious. You should not ignore the smell as it can result in health complications.

You must call a plumber if you can’t address the source of the smell.

A plumber will use plumbing tools to locate the source of the smell and carry out the required repairs or replacement to remove the obnoxious smell.

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