Faecal bacteria has been found in ice from three leading UK coffee chains, during an investigation by the BBC One TV Watchdog programme
A number of iced drinks from Costa Coffee, Starbucks and Caffe Nero contained different levels of the bacteria.
Tony Lewis, spokesperson for the Chartered Institute of Environmental Health, told the BBC that the levels were "concerning" and "should not be present at any level - never mind the significant numbers found".
He described the bacteria as "opportunistic pathogens - the source of human disease".
Seven out of 10 samples of ice at Costa Coffee contained bacteria found in faeces, while three out of 10 samples at Starbuck and Caffe Nero were contaminated with a bacteria known as faecal coliforms.
All three companies said they were now taking action. Costa has updated its ice-handling guidelines and is introducing new ice equipment storage.
Starbucks and Caffe Nero said that they are both conducting investigations into the claims.
Watchdog will be screened on BBC One tonight at 8pm.
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