A team of European researchers found the yeast fungus living on 62 percent of dishwashers, tested around the world. According to the researchers, the black yeasts thrive in extreme temperatures and conditions. They're especially partial to the lungs, so people with lung diseases like cystic fibrosis are most at risk.
The yeast has also shown up on dishes and cutlery cleaned in the dishwashers and the rubber seals, also contained other kinds of fungus.
The study appears in the journal "Fungal Biology."