A "concerning" amount of fecal bacteria was found in iced drinks at several popular coffee shops in the United Kingdom, including Starbucks, according to a new report.

A BBC investigation into the cleanliness of Starbucks, Costa Coffee and Caffe Nero found iced drinks from all three chains contained bacteria known as fecal coliforms.

Fecal coliforms are found in the feces of warm-blooded creatures including humans. According to the Washington State Department of Ecology, fecal coliforms in drinking water can cause minor to major illnesses.

BBC reported that it found the bacteria in three of 10 Starbucks iced drink samples it tested for a TV program that will air Wednesday in Britain.

Three of 10 Caffe Nero drinks also had the bacteria, as well as seven of 10 Costa Coffee drinks tested.

Starbucks told BBC it would conduct its own investigation into the claim.

Clint Davis covers entertainment and trending news topics for the Scripps National Desk. Follow him on Twitter @MrClintDavis. Keep up to date with the latest news by following @ScrippsNational on Twitter.