More than 100 types of bacteria can thrive in microwave ovens

Even the microwave oven in your kitchen is not immune to bacteria.

The radiant environment inside a microwave oven can seem inhospitable to germs. But swabs from microwave ovens in several different areas identified more than 100 bacterial strains, researchers report Aug. 7 in Frontiers in Microbiology. This is the first time scientists have documented the microbial communities living in microwave ovens, according to the researchers.

Microbiologist Manuel Porcar and colleagues wiped the insides—including the walls and turntable—of 30 microwave ovens that were being actively used in three different environments: 10 from kitchens, 10 from laboratories, and 10 from other common spaces such as cafeterias. The samples taken were then transferred to laboratory dishes, all of which led to significant bacterial growth.