Who doesn’t feel instantly energized by the smell of freshly brewed coffee in the morning?

Since we’re all strapped for time, and live in a culture of convenience, it’s no surprise that so many of us rely on our single-cup coffee brewing machines for our caffeine hit. In fact, the National Coffee Association of the USA found that, in 2015, 27% of Americans use a single-cup brewing system, up from a mere 7% just four years ago!

However, this rising trend may be a cause for concern – particularly if you take into account the environmental impact of all these coffee pods, along with the health concerns surrounding the cleanliness of the machines and use of plastics in the pods.

Local CBS news affiliates have reported that Keurig machines are often a disgusting bacteria breeding ground. According to recent tests performed by CBS stations in Pittsburgh, Dallas, and Chicago, Keurig coffee machines came back with findings of E.coli, staphylococcus, streptococcus and pseudomonas aeruginosa and other bacteria festering inside.

The news outlets swabbed various parts of 29 Keurig coffee makers and sent samples to a lab to be analyzed. More than half of the machines came back with bacteria counts in the millions, according to CBS Pittsburgh.

One swab from a Keurig machine in Pittsburgh contained 4.6 million colonies of bacteria and mold. In Dallas, Keurig machines were found with E.coli, staphylococcus, streptococcus and pseudomonas aeruginosa.

Amazingly, 38 percent of coffee drinkers are now using single serve coffee makers like the Keurig.

“It makes me want to cry,” says Amanda Busch, who allowed CBS Pittsburgh to swab her Keurig machine. Busch’s machine came back with 4.6 million colonies of bacteria and mold.

With the tank that fills with water, and a compartment that holds a K cup, Keurig machines create an environment for possible bacteria infections, similar to the kitchen sponge that is often home to a lot of bacteria.

Asked about the situation, University of Arizona germ specialist Kelly Reynolds said, “[Coffee makers] are certainly a moist environment where mold and bacteria are known to grow in high numbers. Our bodies can deal with them, but at some point they’ll grow to levels high enough to cause sickness.”

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