Faecal bacteria has been discovered in ice at three major high street coffee chains, according to an investigation.
Samples from drinks at Costa, Starbucks and Caffe Nero were reportedly found to be contaminated in lab tests carried out by BBC Oneβs consumer series βWatchdogβ.
Faecal coliforms, which contain disease-causing pathogens, were present on seven out of 10 ice samples in Costa, three out of 10 in Caffe Nero and three out of 10 in Starbucks, the BBC said.
Tony Lewis, from the Chartered Institute of Environmental Health, told the programme: βThe level of contamination of faecal bacteria concerns me a great deal. The bacteria found are opportunistic pathogens - the source of human disease.
βThese should not be present at any level - never mind the significant numbers found.β
Cleanliness of tables, trays and high chairs at the chains was also tested at 30 branches.
A Starbucks spokesperson said it takes hygiene βextremely seriouslyβ and βnothing is more importantβ than customer safety.
βWe have moved quickly to conduct our own investigation into the claims about the stores,β he added.
βAll employees nationwide have received updated training on our high standards of hygiene including ice handling.β
Costa said: βWe were disappointed with the findings, especially as these stores are all rated βvery goodβ with a the top hygiene rating of five.
βFollowing these results we took immediate action to review our food safety procedures and have updated our ice-handling guidelines and are in the process of introducing new ice equipment storage across our estate.β
A spokesperson for Caffe Nero described the findings as concerning and added: βA thorough investigation is now under way and the appropriate action will be taken.β
β99% of our stores are rated as very good, good or satisfactory by their local EHO (environmental health officer) - making us one of the most highly rated businesses on the high street,β he said.
The first episode of the new βWatchdogβ programme will air on BBC One on Wednesday at 8pm.