A shocking new study has revealed that microwave ovens can be ideal environments for bacterial growth. It is often believed that the irradiating environment inside the microwave may be inhospitable to microbes.
However, scientists have identified over 100 bacterial strains after analysing microwave oven swabs in several locales.
The study’s findings were published in the Frontiers in Microbiology journal last month.
According to a report by Science News, this is the first time that scientists have documented microbial communities living in microwave ovens.
A team led by microbiologist Manuel Porcar swabbed the insides — including the walls and rotating platter — of 30 microwave ovens that were being actively used in three different settings: 10 from kitchens, 10 from labs and 10 from other shared spaces such as cafeterias. Later, the swabbed samples were then transferred to lab dishes and all of which led to significant bacterial growth.
When the researchers analysed the DNA of the bacterial colonies, it showed they were dominated by Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. Surprisingly, all of these are commonly found on human skin and surfaces that people frequently touch.
Moreover, the cultures from kitchen microwave ovens included bacteria that can cause food-borne diseases, including Klebsiella and Brevundimonas. However, it is unclear how these bacterial strains could survive in microwave ovens.
The researchers emphasised that further work is needed to understand how they’ve adapted to high temperatures and electromagnetic radiation.
Porcar, of the University of Valencia in Spain, notes that the microorganisms they found in domestic microwave ovens were the same as those that can be found on a kitchen surface.
“Some of them are pathogenic, and one must clean the microwave as much as any other kitchen surface,” he says as quoted by Science News. However, he stresses that kitchen microwave ovens aren’t a particular cause for concern. “Nothing to be more worried about than the cleaning of any other part of a kitchen in contact with food.”
