If you've ever noticed a strange pink residue creeping around your shower, bathtub, or sink, you’re not alone — and you might have dismissed it as just another form of harmless bathroom mould. But according to a doctor’s recent warning, that common assumption could be putting your health at risk.
The mystery build-up, often brushed off as a simple cosmetic nuisance, has now been linked to hospitalisations and potential infections — especially for those with weakened immune systems.
So what exactly is this pink gunk? And why is it showing up in your bathroom?
Dr. Karan Raj, a medical professional known for sharing health advice on TikTok, recently addressed concerns after a user revealed they had been hospitalized due to exposure to pink build-up in a shared university bathroom.
According to Dr. Karan, the pink substance often found in bathrooms isn’t mould at all, but a type of bacteria called Serratia marcescens.
“If you've seen this pink slime lurking in your bathroom, it's not mould, it's bacteria,” he explained in a video response. “This bacteria loves damp, moist places and feeds on fatty deposits, like those found in soaps and shampoos. That’s why it thrives in bathroom environments.”
Serratia marcescens produces a reddish-pink pigment known as prodigiosin, giving the bacteria its distinct color, per Infectious Disease Advisor.
It’s commonly found in damp corners of showers, bathtubs, and sinks, particularly where moisture and soap scum build up. While the bacteria is generally harmless for healthy individuals, it can pose health risks for people with weakened immune systems or open wounds.
“In most cases, it’s not dangerous,” Dr. Karan said. “But you want to avoid getting it in your eyes or into cuts, especially if you're immunocompromised.”
According to Infectious Disease Advisor, Serratia marcescens can cause urinary tract infections, respiratory issues, and other complications in vulnerable individuals, and it’s often resistant to multiple antibiotics, making it difficult to treat in medical settings.
The presence of pink slime may also be a sign of poor ventilation and excess moisture, which can contribute to the growth of other, potentially more harmful moulds. “If your home has enough dampness for pink slime to consistently develop, you could also be growing actual household mould, which may lead to respiratory issues or allergies,” Dr. Karan added.
To reduce the risk, Dr. Karan recommends keeping bathrooms well-ventilated. “The first rule of Pink Slime Club is prevention. Keep your shower area dry and ventilated,” he advised. This can include using an exhaust fan, cracking open a window during and after showers, and regularly disinfecting surfaces.
Routine cleaning with antibacterial products, particularly in areas where water pools or soap residue builds up, is also essential. “It’s not just about appearance, it’s about keeping your space safe and healthy,” Dr. Karan concluded.