Study suggests 48% of US soda fountain machines have coliform bacteria

January 9, 2010 A recent study conducted by Hollins University indicates that 48% of sodas from soda fountains in the United States are contaminated with coliform bacteria.

The researchers drew the conclusions from a test of 90 beverages from 30 fountains in fast food restaurants. The bacteria found was a form of fecal contamination, it was discovered, although it was not immediately clear whether it came from the soda fountains themselves, or people with dirty hands.

Other bacteria were also found in the soda samples, including E.coli, present in eleven percent of the tested beverages. Many of the soda drinks apparently fell below the US Environmental Protection Agency's minimum standards for drinking water; regulations state that samples cannot test positive for E.coli bacteria. In total, 20% of soda fountains had more than the maximum recommended levels of bacteria.

"The large number of beverages and soda fountain machines containing E. coli is still of considerable concern [...] and suggests that more pathogenic strains of bacteria could persist and thrive in soda fountain machines if introduced," the authors of the study wrote.

Renee Godard, the study's lead author, and a professor of biology and environmental studies at Hollins University, commented on the findings. "Certainly we come in contact with bacteria all the time. It's simply that some bacteria may potentially cause some disease or gastrointestinal distress. One thing we hesitate with is that people get afraid of bacteria. Many of them are benign or helpful, but certainly, I don't want E.coli in my beverage," she said.

Godard and her team took samples of 90 different beverages from three groups - sugar soda, diet soda, water - from 30 fast-food restaurants in Roanoke, Virginia.

"You can get collections of bacteria in the water line and that then runs through the whole machine and gets in to the beverage. Any time any water or liquid sits somewhere, it's just a breeding ground for bacteria," commented Primary Care Physician Alanna Levine.

Experts suggest that plastic nozzles used on soda fountains might be part of the reason why the study found so much bacteria is present; it takes only a single dirty hand to spread bacteria over a tube, and it could be easily transferred to the rest of the fountain from there.

"It could be from dispensing with a hand that wasn't clean or using wet rags to wipe down the machine. We haven't done the work to really identify those potential sources and how these bacteria get established," Godard said.

A professor at the University of California Davis, however, said he believed that a single localised study wasn't enough to come to a conclusion about soda machines throughout the country. "How sanitation regulations are promulgated and enforced in a community are different. Some communities are more on to it than others. How much of a threat it represents? It's probably limited. Once again, it's a matter of what regulations are in place, who pays attention and whether it's being followed," he said, as quoted by CNN.

The National Restaurant Association responded to the university's findings in an e-mail statement. "While the results of this study are disconcerting, we feel that it isn't representative of our industry and that our guests can safely enjoy beverages from dispensers and single-serve containers alike," the organisation said.

The American Beverage Association also countered the findings. "Fountain beverages are safe. Consumers can rest assured that our industry's fountain beverages pose no public health risk. [...] Importantly, our industry meets, and often exceeds, all government health standards in bringing its products to market."