Reports of fecal bacteria in iced coffee suggest bigger problems, a microbiologist explains

To the question, "Would you like anything else with that?" no one answers "fecal bacteria."

Unfortunately, it may be accompanying orders of iced coffee drinks at three coffee chains in the UK anyways, according to a recent BBC investigation.

The BBC reports that it found "varying levels" of the bacteria in samples of iced drinks from Starbucks, Costa Coffee, and Caffe Nero.

All three companies told the BBC they'd "taken action" on the findings. Starbucks also told the BBC it was also conducting its own investigation and maintained that it takes hygiene "extremely seriously."

The presence of fecal bacteria - which can cause diarrhea if ingested - could be a sign that there are nastier germs also present, said Philip Tierno, a microbiologist at New York University.

"Where there are fecal bacteria present it is an indicator that there could be other germs that are pathogenic [or illness-causing] like Norovirus or hepatitis A or Salmonella that can make you sick," Tierno told Business Insider.

It also suggests that workers at the chains are not keeping themselves clean, that they "have dirty bare hands," he said.

In addition to sampling the ice at 30 of the chains, British researchers also studied their tables, trays, and high chairs. London chain Costa Coffee ranked worst, with seven out of 10 samples "found to be contaminated with bacteria found in feces."

Starbucks and Caffe Nero also tested positive for fecal coliforms in three out of 10 samples.

Business Insider reached out to all three companies but did not immediately hear back.