August 13, 2024

Study Finds Hardy Bacteria Thriving in Microwaves

Researchers have discovered that bacteria can adapt to survive in an unexpected and potentially deadly environment - microwave ovens.

In a recent study, scientists identified bacteria thriving in both domestic and laboratory microwaves, with some strains showing remarkable resistance to the extreme conditions these appliances create.

"Our findings reveal that domestic microwaves host a microbiome similar to that of kitchen surfaces, while laboratory microwaves contain bacteria more resistant to radiation," said Daniel Torrent, a researcher with Darwin Bioprospecting Excellence SL in Paterna, Spain.

The study involved collecting microbe samples from 30 microwaves: 10 from single-household kitchens, 10 from shared spaces like cafeterias and workplaces, and 10 from molecular biology and microbiology labs. Researchers cultured the bacteria and conducted genetic sequencing, uncovering 747 different species across 24 bacterial families.

Interestingly, the microbial communities found in home microwaves overlapped with those in workplace microwaves, containing bacteria commonly found on kitchen surfaces. "Some species, such as Klebsiella, Enterococcus, and Aeromonas, may pose a risk to human health," Torrent noted. However, he emphasized that these microbes do not present a unique or increased threat compared to other kitchen surfaces.

Laboratory microwaves, on the other hand, had the highest diversity of microbes, while home microwaves had the lowest. The study also found that the microbiomes in microwaves closely resembled those found on solar panels. Researchers speculated that the constant thermal shock and electromagnetic radiation from solar panels have a similar effect on bacteria as microwaves, killing off all but the most resilient strains.

Published in the journal Frontiers in Microbiology, the study suggests practical steps to reduce bacterial presence in microwaves. "For both the general public and laboratory personnel, we recommend regularly disinfecting microwaves with a diluted bleach solution or a commercially available disinfectant spray," Torrent advised. He also recommended wiping down the interior surfaces with a damp cloth after each use and cleaning up spills immediately to prevent bacterial growth.

Despite the potential health concerns, Torrent pointed out that these hardy bacterial strains could have industrial applications. Microbes that can withstand the harsh conditions inside microwaves might be valuable for processes requiring especially resilient bacteria.