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Why is My Toilet Seat Turning Blue: 4 Possible Reasons

elongated toilet seat

There is a strange mystery plaguing bathrooms around the world. Sometimes after finishing your business, you go to flush only to notice that your toilet seat looks blue. You are not going crazy. There are reports of people’s toilet seats inexplicably turning blue. The good news is that blue toilet seats, so far, are relatively harmless. The bad news is that the stain, once it sets in, can be extremely difficult to get rid of.

Here are four possible reasons that your toilet seat could be turning blue.

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The 4 Possible Reasons Why Your Toilet Seat is Turning Blue

1. Potent Hormones

The myth is that a blue toilet seat is a sign of pregnancy. There is some circumstantial evidence that this could be the case, but nothing has been explicitly proven. That means that if you spot a blue toilet seat and you suspect you could be pregnant, there could be a connection but not always. Some scientists suspect that blue toilet seats are connected to potent hormones in the body, including estrogen and progesterone. Elevated levels of these two hormones are indeed connected to pregnancy, but there are some gaps in the connection.

First, some people can have high levels of estrogen and progesterone without being pregnant. Second, while these two hormones are hesitantly linked to a blue toilet seat, there is no strong evidence that makes this link a surefire thing.

If you spot a blue toilet seat and suspect that you could be pregnant, it might be prudent to take a pregnancy test just in case. The results could surprise you. But what if you are not pregnant or are someone who is unable to get pregnant? What else could explain a blue toilet seat?

2. Chromhidrosis

Chromhidrosis is a medical condition marked by the production of colored sweat. The condition is extremely rare, but there are documented cases going back as far as 1709. Chromhidrosis is a leading suspect in the mystery of the blue toilet seat. If someone is unwittingly suffering from chromhidrosis, they could be staining their toilet seat via their sweat.

The sweat produced by people with chromhidrosis is a blue or gray color. Sweat from your legs or backside that is tinged with color from chromhidrosis could be causing your toilet seat to turn blue slowly over time. While chromhidrosis could be causing your toilet seat to turn blue, the condition is extremely rare, and the likelihood that you have this condition is very small.

If you suspect that you do have chromhidrosis, do not worry. The condition is completely harmless. While strange, chromhidrosis has no adverse side effects other than colored sweat.

Close up flushing water in clean toilet bowl
Image By: SumanBhaumik, Shutterstock

3. Clothing Dye

One of the most straightforward explanations for a blue toilet seat is clothing dye. Blue jeans are known to bleed color in certain situations. It could be as simple as leaving blue dye on your toilet seat while pulling your pants up and down. Over time, you will leave enough dye behind to start staining the normally white toilet seat. This is especially true if your pants are wet for any reason, including sweat, a spill, or having been recently washed. If you wear blue jeans a lot or blue pants, you could slowly stain your toilet seat with each use.

4. Bacteria Growth

Another theory is that certain bacteria can grow and interact with cleaners, sweat, and dirt to leave blue streaks on a toilet seat. This is one of the least well-understood explanations for the blue toilet seat phenomenon, but it is still compelling. There is plenty of bacteria present on people’s skin and on bathroom surfaces. It is not out of the question to think that these bacteria colonies interact with other things in the environment to produce a blue color.

Bacteria colonies can do many strange things to the macroscopic world despite being invisible to the naked eye. There have even been bacteria colonies that have caused people’s skin and wounds to glow in the dark due to the invisible growth of certain species of bacteria. It is not out of the question to think that unique bacteria growing under specific conditions could cause a toilet seat to turn blue. Odder things have happened in nature.

flushing water in white toilet bowl
Image By: Karolina Grabowska, Pexels

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But No One Knows for Sure

The bottom line is that while these theories are interesting, compelling, and have evidence to support them, no one knows what causes a toilet seat to turn blue. Blue toilet seats are still largely a mystery. None of these theories have been proven by science beyond the shadow of a doubt.

Many of the links are circumstantial or could simply be weird coincidences. The universe is filled with strange interactions. One of these explanations could be the link between you and your oddly blue toilet seat, but no one can be certain.

Image Credit: Soonthorn Wongsaita, Shutterstock

Cleaning Up the Blue Toilet Seat Stains

Blue toilet seats can be unsightly and unsettling to look at. If you want to remove the blue stain, use heavy-duty cleaners. The bad news is that many people cannot fully remove the blue color from the toilet seat once it sets in. That is because the color is likely connected to bacteria, bodily fluids, or hormones which can make it extremely hard to dislodge.

You can try using bleach, vinegar, or enzyme cleaners. In each case, heavy scrubbing will be needed, and that might not even be enough to remove the color completely. Some people have reported good results from using a magic eraser to tackle the job.

Do not be discouraged if you cannot get the color out of your toilet seat. You are not alone. Many people have struggled to remove the blue color from their toilet seats once it appears. In some cases, it might be necessary to change the toilet seat completely.

house divider Conclusion

Blue toilet seats continue to remain somewhat of a mystery. Scientists and professionals have weighed in on the matter with multiple theories, but none have been singled out as the best answer to the question of the blue toilet seat. It is possible that there is a connection to sweat, bacteria, or hormones. It could also be something as simple as clothing dye or cleaners leaving colored marks on your toilet. It is impossible to know for sure, but these explanations might offer some relief to the mystery happening in your home.

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Featured Image Credit: Sidorov_Ruslan, shutterstock


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