Are Extremophiles Our Roommates?

Extremophiles are microorganisms that can survive in extreme conditions, such as high temperatures or great acidity. A recent study has found extremophiles in a location much more familiar to us, and it’s actually in the homes of humans.

Thermus Scotoductus cells, found in the water heaters of homes. Image courtesy of Science Daily

The study took samples from water heaters across all 50 states. Around 50% of the tested samples found evidence of microbes, with Thermus scotoductus being the most dominate species in all positive samples. The extremophiles pose no health risks to humans, making water containing the microbes still completely safe to consume. Thermus scotoductus has previously been found in hot springs, hydrothermal waters, and deep in a gold mine. Scientists are surprised to see such a large presence of this species in water heaters even in places with such a large abundance of other microbes, such as near Yellowstone. Even though we traditionally think of extreme conditions as “weird” or “inaccessible” parts of nature, our perception is shifting with this discovery.

And why do extremophiles colonize in water heaters? Scientists say the high temperatures and low levels of organic matter make the heaters an ideal environment for microbes. They can even survive being transported between water heaters because they can survive cooler temperatures as well. There is a correlation between colder temperatures outside and a greater presence of microbes, possibly because colder weather results in increased water heater temperatures. Scientists are still working to understand how the microbes enter our homes.

To read more, visit this article.