Scientists discover potentially harmful “dishwasher fungus”

Scientists have found a fungus that grows in dishwashers, is resistant to detergents and hot water, and potentially harmful to human health.

New research published in British journal Fungal Biology found the average home’s dishwasher — in particular the rubber seal on the door — is the perfect breeding ground for potentially disease-causing fungal flora.

Some types of “extremotolerant fungi,” which includes black yeasts, are remarkably resistant to high temperatures, detergents, salt concentrations and both acid and alkaline water types, according to the study.

Researchers at the University of Ljubljana, University of Amsterdam, the Research Center for Medical Mycology in Beijing and the Sun Yat-sen University in China contributed to the study.

“This is a combination of extreme properties not previously observed in fungi,” says the study, which appears in the latest edition of Fungal Biology, published by the British Mycological Society.

The study looked at a sample of 189 private homes in 101 cities on six continents.

Researchers found that 62 percent of the dishwashers contained fungi in the door's rubber seal, and 56 percent had potentially harmful “black yeasts."

Black yeasts called Exophiala dermatitidis and E. phaeomuriformis were found. Both species "are known to be able to cause systemic disease in humans and frequently colonize the lungs of patients with cystic fibrosis," the study says.

“The invasion of black yeasts into our homes represents a potential health risk,” it says.

The study did not say whether the dishwasher fungi had posed any threat to health, and noted that “further search is imperative,” Agence France-Presse reports.

The types of fungi found in the dishwashers are rarely encountered in nature, and seem to have found an evolutionary benefit in their dishwasher habitat, where they can thrive on the heat and moisture, AFP says.