It sounds like the premise for a low-budget horror film: a potentially deadly fungus is found living in dishwashers all over the world. It's happening, but most healthy individuals have nothing to worry about.
Researchers at the University of Ljubljana in Slovenia sampled over 180 dishwashers from around the world and found evidence that black yeasts Exophiala dermatitidis and E. phaeomuriformis are growing on the rubber door gaskets of more than half of in-home dishwashers they sampled. Their research was published in the journal Fungal Biology.
While the yeasts can pose a danger to individuals with severely compromised immune systems, especially people with cystic fibrosis, most people needn't worry about getting sick from their dishwasher. Experts say that the likelihood of death from dishwasher-borne black yeast is rare even for those who are extremely immunocompromised.
What has alarmed scientists, however, is that the yeasts can survive in the extreme environment of a dishwasher, where temperatures frequently top 158 degrees Fahrenheit, water can either be acidic or alkaline and salt is in high concentration. No other fungi have been found that could live in such a harsh habitat.
The Slovenian researchers theorized that the yeasts found in dishwashers had evolved to live there, and may have the potential to be a greater threat to humans.