Photo illustration by Stephanie Klein-Davis | The Roanoke Times

Drinking a beverage from a restaurant's soda fountain machine could make you sick, claims a research team at Hollins University.

Water, Coke, Pepsi and these soda's diet versions, when dispensed through fountain machines, contained bacteria that have the potential to cause gastrointestinal illness for people who consume them, according to research by a five-person team of faculty members and students.

Their research, which tested beverages served from 31 soda machines at Roanoke Valley fast-food establishments, suggests that the interior tubing inside these machines harbors harmful bacteria.

No food-borne illnesses have been linked to these machines in Virginia. Even so, this group of professors and students hopes that the findings, which appeared online last month in the International Journal of Food Microbiology, will encourage restaurants and public health officials to take a closer look at contaminants that may lurk inside these machines.

The research "suggests that there is really a problem with our food delivery system," said Renee Godard, a professor of biology and director of environmental studies at Hollins and co-author of the study. "We need to fix the problem, so it won't become a bigger one."

The Virginia Department of Health plans to make some changes in its cleaning instructions for restaurants as a result of this study. Chris Gordon, environmental health manager for the health department, said restaurant inspectors will remind eateries to clean machine tubing once a month, which is suggested by the manufacturer and encouraged through the Hollins study.

The health department requires that nozzles on these machines be cleaned daily, but inspectors who visit most restaurants twice a year do not visually evaluate the tubing through which beverages are dispensed, Gordon said.

The majority of restaurateurs surveyed through the Hollins research said they do not clean these tubes.

The finding is not unique to the Roanoke Valley, Godard said. It's likely happening at restaurants nationwide.

She would not reveal which local restaurants her team visited to obtain beverage samples, but they were "typical chain restaurants that we all encounter," she said.

"Often you think about how you go and have a meal at a restaurant, and your stomach feels a little wobbly," Godard said. "We want to blame the food."

The idea that soda machines could be linked to contaminated beverages first came to the attention of a Hollins biology lecturer, Amy White, in the spring of 2008 during a microbiology lab. White asked students to collect samples of liquids to test for coliform bacteria.

One student gathered water dispersed from a restaurant's soda fountain. After testing it, the student discovered coliform bacteria, which can be found in human or animal waste. The U.S. Environmental Protection Agency prohibits drinking water that contains coliform bacteria.

After this finding and a subsequent pilot study by another Hollins student, three Hollins professors, including Godard and White, along with two other students, got onboard.

They collected 93 beverage samples in May and June from 31 soda machines at fast-food businesses in the Roanoke Valley, some at different times of the day. They performed various tests and paid a Virginia Tech microbiology lab to help as well.

The results alarmed them.

More than 70 percent of the beverages contained bacteria, while a smaller percentage had bacteria that exceeded the EPA's drinking water standards. Their research found that 48 percent had coliform bacteria and 12 percent had E. coli, an indication of human or animal wastes.

When consumed, this bacteria can cause gastrointestinal pain and sicken people with weak immune systems, Godard said.

The Hollins researchers presume that bacterial communities are growing within the moist machine tubing. The liquids, such as water, likely became contaminated after traveling through the tubing, Godard said.

But the team has not tested the tubing for contamination. They're considering a future study on the machines' tubing alone.

Manufacturers of soda machines require the interior tubes to be flushed with sanitizer monthly, the Hollins research claims. But the team found that nine out of 10 restaurants clean only the machines' nozzles, not the tubing.

One local restaurateur said he does not know how to clean the tubing in a soda machine. Todd Lancaster, the owner of several Awful Arthur's Seafood Co. restaurants in the Roanoke and New River valleys, said someone needs to design a device that puts enough pressure on cleaning solution to force it through a machine's tubing.

"If the health department starts looking at fountain machines, obviously we're going to clean them," Lancaster said. "It's in their hands, if they want to enforce it ... Right now as it is, it would be hell to clean those lines."

Lancaster said his employees clean the nozzles on fountain machines each day.

The same daily cleaning practice happens at Henry's Memphis BBQ in Roanoke and Salem, said owner Henry Caldwell.

He said the health department and his vendor do not provide guidelines on cleaning soda machine tubing.

Restaurant inspectors for the Virginia Health Department are required only to visually inspect nozzles of soda machines for mold and soil contamination during their twice yearly inspections, Gordon said.

It would be difficult for an inspector to disassemble a soda machine to inspect its tubing, he said.

An inspector asks restaurateurs if they are cleaning the machine's tubing, though the department does not give guidelines about how frequently cleaning should take place.

The recommended monthly cleanings suggested in the Hollins study will "inform our discussions" with restaurants about how often they should sanitize these soda machines, Gordon said.

Still, he reiterated that "We've never had a reported illness outbreaks associated with soda beverage machines."

"You can find the pathogens ... not necessarily all of them will cause food-borne illness," Gordon added.

Even so, Godard and her Hollins research team believe that prevention is key to stopping potential sickness from happening.

"I don't think any of us want to be alarmists about this," Godard said. "We see it as an overall problem, not just any one problem."

Still, she no longer orders drinks from a restaurant's soda fountain. Though she does not drink sodas often, Godard said she now prefers to drink water from a tap as a result of the study's findings.

"It's not like people are dropping dead," she said. "We just don't know what it is we are being exposed to."